[0001] The present invention refers to the management techniques of the transportation of
packet data services in a telecommunication network, in particular, to a method for
managing transport tunnels of packet data services in a LTE technology telecommunication
network.
[0002] The present invention further refers to a network architecture configured to implement
such method.
[0003] There are telecommunications networks of the professional type that are referred
as crucial as regards the general management of data traffic, in particular, data
service transportation.
[0004] An example of such type of networks is the professional telecommunications network
TETRA (from the English acronym,
Terrestrial Trunked Radio), i.e., the dedicated telecommunications network that is used in the professional field,
for example by law enforcement agencies (police, fire departments, and so on), by
hospital entities, first aid facilities, and so on.
[0005] The professional telecommunications network TETRA, which initially was a circuit
mode network, underwent an evolution over the years, and it can be now implemented
also as a packet network, i.e., a so-called IP network (from the English acronym,
Internet Protocol), i.e., as a Full-IP network infrastructure.
[0006] The professional telecommunications network TETRA has determined characteristics
in order to ensure determined types of data services (for example, group calls).
[0007] A limitation of such type of network is related to the data transmission band capacity
available, especially in view of being able to support, by professional users, further
broad-band data services.
[0008] In such context, many of the current standards that are used in the professional
telecommunications networks are not able to ensure some multimedia data services,
in particular, they are not able to support the most evolved data services, such as
high-definition multimedia videos.
[0009] In order to overcome these limitations, it has been decided to migrate the determined
services, also in the professional field, towards a more evolved telecommunications
network, even if typically commercial, such as a telecommunications network 4G, i.e.,
the LTE technology telecommunications network (from the English acronym,
Long Term Evolution).
[0010] In fact, the LTE technology is considered as the technology that, also in the next
years, both on a commercial and a professional viewpoint, will be the most suitable
to meet the required needs.
[0011] As it is known, the LTE technology, compared to the previous 3G standards (3GPP,
from the English acronym,
3rd Generation Partnership Project), for example, UMTS (from the English acronym,
Universal Mobile Telecommunications System), with a circuit mode technology, is instead a Full-IP packet technology.
[0012] Furthermore, at the regulations level, the LTE technology was characterized in a
very detailed manner in terms quality of service.
[0013] In this regard, a concept of quality of service was defined which allows, depending
on the type of data service required by a user (professional or not professional),
characterizing the packet data processing for the required service in the most suitable
manner.
[0014] This concept was standardized by defining, in the so-called
Evolved Packet System (EPS) the so-called EPS bearers, i.e., packet data traffic tunnels within a LTE-technology
telecommunications network, to which, in terms of quality of service, determined characteristics
are assigned, applied on both the radio segment and the IP transportation segment,
for one or more packet data services required by a user. Such transport bearers are
built between each User Equipment (UE, from the English acronym,
User Equipment) and the access network (E-UTRAN, from the English acronym,
Evolved UMTS Terrestrial Radio Access Network) and between the gateways (S-GW or
Serving GateWay, P-GW or
PDN (Packet Data Network) GateWay) of the packet data traffic transportation and management network (EPC, from the English
acronym
Evolved Packet Core).
[0015] However, the definition and set-up of such transport bearers requires both signaling
operations between the several elements of the architecture involved in the data traffic
management (user terminals, access network, packet data traffic transportation and
management network) and operations necessary for the creation of such bearers. All
of this, of course, involves a commitment of the involved network elements especially
on a computational viewpoint.
[0016] Furthermore, each time the operative conditions require it, it is necessary to "destruct"
or "pre-empt" the bearers previously built and to build new ones.
[0017] It shall be apparent that, in the case that many bearers are open per packet data
services of a different type, among multiple user terminals (UE) and the E-UTRAN access
network, the impact that would be on the computational performance of the network
in having to pre-empt such bearers and creating new ones will increase as the number
of bearers and the number of user terminals increase.
[0018] Furthermore, there would be a need for pre-empting also the bearers built between
the E-UTRAN access network and the packet data traffic management network EPC. Also
in this case, the pre-emption and construction of other bearers may involve a high
commitment on a computational viewpoint for the EPC network.
[0019] An increase of the computational load is inevitably aimed to degrade the performance
of the packet data services offered by the network from a quality of service viewpoint
(for example, loss of data packets, delay, delay change, and so on).
Document
WO 2008/008990 discloses a method for managing transport tunnels of packet data services usable
by a user in a LTE Technology telecommunications network.
[0020] The drawbacks stated above, which are already critical for the voice and data services
in a LTE-technology telecommunications network of the commercial type, would be still
more amplified in the case, to date ongoing, that a LTE-technology telecommunications
network was used also for professional services.
[0021] In fact, during critical events in which many roaming professional users could need
to use both advanced data services (for example, high-definition videos) and standard
services (for example, a voice service), the processing operations required for the
management of a high number of bearers risk to compromise the quality of service necessary
for the service or the data services of the network.
[0022] The object of the present invention is to devise and provide a method for managing
transport tunnels of packet data services in a LTE-technology telecommunication network
that allows at least partially obviating the drawbacks set forth above with reference
to the prior art.
[0023] Such object is achieved by a method for managing transport tunnels of packet data
services in accordance with the claim 1.
[0024] It is the object of the present invention also a network architecture. as defined
by the independent claim 12, implementing such method.
[0025] Further characteristics and advantages of the method according to the invention will
be apparent from the description set forth below of preferred embodiment examples,
given by way of illustrative, non-limiting example, with reference to the appended
figures, in which:
- Fig. 1 schematically illustrates, by a block diagram, from a logic viewpoint, a network
architecture according to an embodiment of the present invention;
- Fig. 2 schematically illustrates, by a further block diagram, on a further logic viewpoint
and a protocol viewpoint, the network architecture of Fig. 1;
- Fig. 3 schematically illustrates, from a logic viewpoint, data packets transportable
in the network architecture of Fig. 1;
- Fig. 4 schematically illustrates, by a block diagram, a method for managing transport
tunnels in accordance with an embodiment of the present invention;
- Fig. 5 illustrates a table representative of the management of the transport tunnels
of packet data services in the network architecture of Fig. 1, obtained by implementing
the method for managing transport tunnels according to an embodiment of the invention,
and
- Fig. 6 illustrates a table representative of an aspect of the method for managing
transport tunnels, according to a further embodiment of the invention.
[0026] It is pointed out that, in the figures, the like or similar elements are indicated
by the same numeric and/or alphanumeric references.
[0027] With particular reference to Fig. 1, a network architecture or infrastructure is
now described, generally indicated with the numeral reference 100, in which the method
for managing transport tunnels (bearers) of packet data services according to the
present invention can be implemented.
[0028] The network architecture or infrastructure 100, herein below also referred to as
network architecture, or simply network, is preferably in LTE (
Long Term Evolution) technology.
[0029] Such network architecture 100 can be configured for use in the commercial field or
for use in the professional field, or both.
[0030] It is pointed out that by network in the commercial field is meant the standard telecommunications
network used by standard users, while by network in the professional field is meant
a telecommunications network used in the professional field, for example, by law enforcement
agencies (police, fire departments, and so on), by hospital entities, first aid facilities,
and so on.
[0031] The network architecture 100 comprises at least one user equipment UE 1.
[0032] The user equipment 1 is, for example, a mobile electronic device, such as, by non-limiting
example, a cell phone, a smartphone, a tablet, a mobile computer (notebook), a palmtop
computer of the PDA (Personal Digital Assistant) type, and so on.
[0033] The network architecture 100 further comprises an E-UTRAN (
Evolved UMTS Terrestrial Radio Access Network) access network 2.
[0034] The User Equipment UE 1 is configured to be operatively connected to the E-UTRAN
access network 2.
[0035] In more detail, the user equipment UE 1 is operatively connected to the E-UTRAN access
network 2 by an interface of the radio IR LTE-Uu type.
[0036] The E-UTRAN access network 2 comprises at least one first access network apparatus
(eNodeB,
evolved Node B) 3. Such at least one first access network apparatus 3, typically a Base Transceiver
Station BTS, integrates all the control functionalities thereof.
[0037] It shall be noticed that the E-UTRAN access network 2, besides said at least one
first access network apparatus 3, comprises a plurality of access network apparatuses,
each being completely similar to said at least one first access network apparatus
3. In Fig. 1, by way of non-limiting example, the E-UTRAN access network 2 comprises
at least one second access network apparatus (eNodeB) 3'.
[0038] The user equipment UE 1 is configured to be operatively connected to said at least
one first access network apparatus 3 of the E-UTRAN access network 2. In addition,
the User Equipment UE 1 is also configured to be operatively connected to any of the
access apparatuses of said plurality of access network apparatuses, for example, to
said at least one second access network apparatus 3'.
[0039] Said at least one first access network apparatus 3 and said at least one second access
network apparatus 3', and generally all the access network apparatuses of the above-mentioned
plurality of access network apparatuses, are mutually operatively connected by a first
interface of the logic type I1 for the transportation of the Control plane C-plane
necessary to create the data transport flow (for example, set up messages of the transportation
part), and a second interface of the logic type I2 for the transportation of the User
plane U-Plane.
[0040] It shall be noticed that the messages that are transmitted separately, at the logic
level, on the first interface of the logic type I1 and on the second interface of
the logic type I2 could be transmitted, at the physical level, on the same communication
channel (for example, cable or optical fibre). For example, it is pointed out that
in the standard 3GPP the first interface of the logic type I1 and the second interface
of the logic type I2 are part of a same interface of the logic type X2.
[0041] In Fig. 1, between said at least one first access network apparatus 3 and said at
least one second network apparatus 3', the first interface of the logic type I1 is
represented by a hatched line, while the second interface of the physical type I2
is represented with a continuous line.
[0042] The network architecture 100 further comprises a packet data traffic management network
EPC (Evolved Packet Core) 4 operatively connected to said E-UTRAN access network 2.
[0043] The E-UTRAN access network 2 and the packet data traffic management network EPC 4
are a part of the so-called Evolved Packet System, EPS.
[0044] In more detail, the packet data traffic management network EPC 4 comprises a Mobility
Management Entity MME 5, herein below also simply entity MME 5.
[0045] As illustrated in Fig. 1, the entity MME 5 is operatively connected to said E-UTRAN
access network 2, for example, to said at least one first access network apparatus
3, by a corresponding first interface of the logic type I1, S1-MME (also illustrated
by a hatched line), used for the transportation of the Control plane (C-plane).
[0046] The network architecture 100 further comprises a entity HSS (from the English acronym,
Home Subscriber Database) 6, operatively connected to the packet data traffic management network EPC 4.
[0047] The entity HSS 6 is a server of the operator, which provides packet data services
to the users, comprising information regarding the subscriptions of the users and
configured to carry out the functions that are necessary to the management of the
packet data services of the users.
[0048] The entity HSS 6 is operatively connected to the packet data traffic management network
EPC 4 by a corresponding first interface of the logic type I1 SG3 (also represented
by a hatched line) for the transportation of the Control plane (C-plane) necessary
to the management of the information regarding the subscriptions of the users.
[0049] Referring back to the packet data traffic management network EPC 4, it further comprises
at least one first data traffic management gateway 7, which could typically carry
out router functions.
[0050] Said at least one first data traffic management gateway 7 is operatively connected
to said Mobility Management Entity MME 5 by a corresponding first interface of the
logic type I1 S11 (also represented by a hatched line), used for the transportation
of the Control plane (C-plane).
[0051] Furthermore, said at least one first data traffic management gateway 7 is operatively
connected to the E-UTRAN access network 2, for example, to said at least one first
access network apparatus 3, by a corresponding second interface of the logic type
I2 S1-U (represented with a continuous line), used for the transportation of the packet
data traffic.
[0052] The interface of the logic type called S1-U is traceable in the specifications 3GPP
TS 36.300 for the E-UTRAN access network and 3GPP TS 23.401 for the data traffic management
network EPC.
[0053] In the embodiment of Fig. 1, said at least one first data traffic management gateway
7 is the so-called S-GW, from the English acronym
Serving-GateWay, configured to the routing of the Control plane (C-plane) and of the data traffic.
[0054] The network architecture 100 further comprises at least one packet data service network
PDN (Packet Data Network) 8 configured to provide data services on demand by a user,
by said at least one user equipment UE 1.
[0055] The packet data service network PDN 8 is the service network of an operator, for
example, a telephone operator, who provides precisely packet data services, also advanced,
in the commercial field or in the professional field, or both.
[0056] As illustrated also in Fig. 1, the packet data traffic management network EPC 4 is
operatively interposed between the E-UTRAN access network 2 and the packet data service
network PDN 8.
[0057] Referring back again to the packet data traffic management network 4, it further
comprises at least one second data traffic management gateway 9, also typically a
router.
[0058] Said at least one second data traffic management gateway 9 is operatively interposed
between said at least one first data traffic management gateway 7 and said packet
data service network PDN 8.
[0059] In particular, said at least one second data traffic management gateway 9 is operatively
connected to said at least one first data traffic management gateway 7 by a corresponding
first interface of the logic type I1 and a corresponding second interface of the logic
type I2 (respectively illustrated by a hatched line and a continuous line), for the
transportation of the Control plane (C-plane) (11) and the packet data traffic (12).
[0060] Also in this case, the interface of the logic type called S5, of which the first
interface of the logic type I1 and the second interface of the logic type I2 are a
part, is detailed in the specifications 3GPP TS 36.300 and 3GPP TS 23.401.
[0061] Furthermore, said at least one second data traffic management gateway equipment 9
is operatively connected to the packet data service network PDN 8 by a corresponding
second interface of the logic type I2 SGi, for the transportation of data traffic.
[0062] In the embodiment of Fig. 1, said at least one second data traffic management gateway
9 is the so-called P-GW, from the English acronym
PDN-GateWay, configured to the routing of the data traffic coming from the packet data service
network PDN 8.
[0063] It is pointed out that the embodiment of Fig. 1 shows a network architecture 100,
in which the reference points for the present invention are the second interface of
the logic type S1-U between said at least one access network apparatus 3 of the E-UTRAN
access network 2 and said at least one first data traffic management gateway 7 (S-GW)
and the second interface of the logic type I2 between said at least one first data
traffic management gateway 7 (S-GW) and said at least one second data traffic management
gateway 9 (P-GW), represents a "non-roaming" network architecture configured to the
data traffic management, the reference template of which is detailed in the specification
3GPP TS 23.401.
[0064] In accordance with other embodiments, not shown in the figures, the network architecture
100 may comprise other and additional interfaces of the logic type which can be considered
as reference points for the present invention, as long as they allow the network carrying
out the same actions relative to the packet data traffic transportation, independently
from the fact that they belong to other network architectures defined in different
current or future specifications 3GPP.
[0065] By way of example, the network architecture 100, in accordance with a further embodiment,
again defined based on the specification 3GPP TS 23.401, can be configured to the
roaming packet data traffic management. In such a case, to the purposes of the present
invention, a reference point is a further interface of the logic type S8 between said
at least one first data traffic management gateway 7 (S-GW) and said at least one
second data traffic management gateway 9 (P-GW).
[0066] Referring back again to the embodiment of Fig. 1, the packet data traffic management
network EPC 4 comprises said at least one first data traffic management gateway 7
(S-GW) and said at least one second data traffic management gateway 9 (P-GW), which
are mutually distinct and configured, respectively, to route the packet data traffic
from said at least one second data traffic management gateway 9 (P-GW) to the E-UTRAN
access network 2, by said at least one first data traffic management gateway 7 (S-GW),
and to route the data traffic from said packet data service network PDN 8 and said
at least one first data traffic management gateway 7 (S-GW), by said at least one
second data traffic management gateway 9 (P-GW).
[0067] In this regard, said at least one first data traffic management gateway 7 (S-GW)
is configured to the management of transport tunnels (bearers) of data services in
accordance with the management method that is the object of the present invention,
described herein below.
[0068] Furthermore, in the embodiment of Fig. 1, also said at least one second data traffic
gateway 9 (P-GW) is configured to the management of transport tunnels (bearers) of
data services in accordance with the management method that is the object of the present
invention, described herein below.
[0069] In a further embodiment (not shown in the figures), alternative to the one described
above, the data traffic management network EPC 4, especially in the case that the
network to be managed has reduced dimensions, may comprise only one functional entity,
such as a data traffic management gateway, for example, said at least one first data
traffic management gateway 7 (or said at least one second data traffic management
gateway 9), configured, in hardware or in software, for example on the same server,
to carry out the functions of both said at least one first data traffic management
gateway 7 S-GW and said at least one second data traffic management gateway 9 P-GW,
described separately above with reference to the embodiment of Fig. 1.
[0070] Therefore, at a general level, said at least one first data traffic management gateway
7 (or 9) is operatively interposed between said at least one first access network
apparatus (eNodeB) and said at least one packet data service network PDN 8. Said at
least one first data traffic management gateway 7 (or 9) is a functional entity configured,
in hardware and/or in software on an apparatus, to carry out the functions of the
gateway S-GW and the gateway P-GW.
[0071] Also in this embodiment, said at least one first data traffic management gateway
7 (or 9) is configured to the management of transport tunnels (bearers) of packet
data services in accordance with the management method that is the object of the present
invention, described herein below.
[0072] Furthermore, in this embodiment, said at least one first data traffic management
gateway 7 (or 9) is operatively connected: to the Mobility Management Entity MME 5
by a corresponding first interface of the logic type S11 for the transportation of
the Control plane (C-plane); to the E-UTRAN access network 2, in particular, to said
at least one first access apparatus 3 by a corresponding second interface of the logic
type S1-U for the packet data traffic transportation; to the packet data service network
PDN 8 by a corresponding interface of the logic type SG1 for the packet data traffic
transportation.
[0073] Furthermore, in other embodiments, the number of functional elements of the network
architecture 100 can be different according to the intended use of the network (the
commercial or the professional field).
[0074] For example, in the case that the network 100 is intended to the commercial field
(an embodiment not shown in the figures), in which the E-UTRAN access network 2 comprises
a plurality of access apparatuses eNodeB, completely similar to said at least one
first access network apparatus 3, the data traffic management network EPC 4 comprises
one or more gateways S-GW and one or more gateways P-GW, as a function of the number
of packet data service networks PDN that require to be operatively connected to the
packet data traffic management network EPC 4.
[0075] In accordance with a further embodiment (not shown in the figures), an access network
apparatus eNodeB, for example, said at least one first access network apparatus 3,
can be operatively connected to a first packet data traffic management network EPC
configured for use in the commercial field (network of a marketing operator) and a
second packet data traffic management network EPC configured for use in the professional
field (network of the professional operator).
[0076] In such a case, according to the type of service required by a user, by said access
network apparatus eNodeB, a routing policy will be provided, by the access network
apparatus, such as to route the request to the first packet data traffic management
network EPC (network of the marketing operator) or the second packet data traffic
management network EPC (network of the professional operator).
[0077] It is pointed out that the network architecture 100 of the embodiment of Fig. 1 allows
the traffic of data services of the point-to-point type.
[0078] In fact, in the case that a request of service is accepted, said at least one first
data traffic management gateway 7 (S-GW) is configured to establish transport tunnels
(bearers), i.e., the second interfaces of the logic type (those that are represented
in Fig. by a continuous line), for each User Equipment UE that required that type
of service. Therefore, the connection between the packet data traffic management network
EPC 4 and each User Equipment is precisely of the point-to-point type.
[0079] In accordance with a further embodiment, not shown in the figures, the network architecture
is configured to the management of services, allowing establishing corresponding connection,
of the multi-cast type.
[0080] In fact, according to this embodiment, the network architecture further comprises
a further functional logic entity, i.e., a further data traffic management gateway
eMBMS (from the English acronym,
evolved Multicast Broadcast Multimedia Service), operatively connected between the packet data service network PDN 8 and the E-UTRAN
access network 2.
[0081] In more detail, the further data traffic management gateway eMBMS is operatively
connected to the E-UTRAN access network by a corresponding second interface of the
logic type M1, completely similar to the second interface I2 S1-U of Fig. 1, for the
transportation of the packet data traffic.
[0082] It is pointed out that such second interface of the logic type M1, defined in the
specification 3GPP TS 23.246, is also to be considered as a possible reference point
for the present invention.
[0083] Furthermore, the further data traffic management gateway eMBMS is operatively connected
to the packet data service network PDN by a corresponding second interface of the
logic type, completely similar to the second interface I2 SGi of Fig. 1, for the transportation
of the data traffic.
[0084] Such further data traffic management gateway eMBMS is configured to receive in a
single flow the data coming from the packet data service network PDN and to send such
data, instead by a plurality of transport tunnels, by a single transport tunnel to
the access network E-UTRAN, i.e., to an access apparatus eNodeB which, in turn, in
multi-cast mode, will convey the data corresponding to a predetermined service to
all the user equipment UE from which the request of the specific service has come.
[0085] In this embodiment, in an up-link direction between each user equipment UE and the
packet data traffic management network EPC, a transport tunnel (bearer) is present
for each user equipment, while in the down-link direction between a further packet
data traffic management network eMBMS and each user equipment UE a single transport
tunnel (bearer) is present, which is generated by the further data traffic management
gateway eMBMS, between the same and the access network E-UTRAN.
[0086] With reference to Fig. 2, the network architecture 100 is illustrated, by a block
diagram, both on a further logic viewpoint (lower portion of Fig. 2) and on a protocol
viewpoint (upper portion of Fig. 2).
[0087] From the left to the right side, in the scheme of Fig. 2, there are illustrated,
respectively:
- the at least one user equipment UE 1;
- the interface of the radio IR LTE-Uu type between the at least one user equipment
UE and the E-UTRAN access network 2;
- the at least one first access network apparatus eNodeB 3 belonging to the E-UTRAN
access network 2;
- the second interface of the logic type I2 S1-U between said at least one first access
network apparatus eNodeB 3 and the packet data traffic management network EPC 4;
- said at least one first data traffic management gateway 7 (S-GW) belonging to the
packet data traffic management network EPC 4;
- the second interface of the logic type I2 S5 between said at least one first data
traffic management gateway 7 (S-GW) and said at least one second data traffic management
gateway 9 (P-GW), also belonging to the data traffic management network EPC 4;
- the at least one second data traffic management gateway 9 (P-GW) of the data traffic
management network EPC 4;
- the second interface of the logic type I2 SGi between the at least one second data
traffic management gateway 9 (P-GW) and the packet data service network PDN 8;
- the packet data service network PDN 8;
[0088] As stated above, in the upper portion of Fig. 2, the network architecture 100 is
illustrated from a protocol viewpoint, i.e., each functional entity, listed above,
is illustrated by the corresponding communication protocol by indicating, at each
level of the communication protocol, the reference acronym.
[0089] In the lower portion of Fig. 2, the network architecture 100 is illustrated from
a logic viewpoint by a further block diagram.
[0090] In particular, in accordance with Fig. 2, the network architecture 100 is configured
to establish:
- an up-link communication channel, indicated with the reference UPL, between said at
least one user equipment UE 1 and the packet data service network PDN 8;
- a down-link communication channel, indicated with the reference DWL, between the packet
data service network PDN 8 and said at least one user equipment UE 1.
[0091] From a logic viewpoint, in the up-link communication channel UPL, a transport tunnel
(bearer) of packet data traffic in up-link can be defined, comprising:
- a first part of data traffic transport tunnel b1 between said at least one user equipment
UE 1 and said at least one access network apparatus eNodeB 3, defined therefore on
the interface of the radio IR LTE-Uu type (in the specification 3GPP TS 23.401, such
part of transport tunnel is defined "radio bearer");
- a second part of data traffic transport tunnel b2 between said at least one access
network apparatus eNodeB 3 and said at least one first data traffic management gateway
7 (S-GW), defined therefore on the corresponding second interface of the logic type
I2 S1-U for the transportation of data traffic (in the specification 3GPP TS 23.401,
such part of transport tunnel is defined "S1-U bearer");
- a third part of data traffic transport tunnel b3 between said at least one first data
traffic management gateway 7 (S-GW) and said at least one second data traffic management
gateway 9 (P-GW), defined therefore on the corresponding second interface of the logic
type I2 S5 for the transportation of data traffic (in the specification 3GPP TS 23.401,
such part of transport tunnel is defined "S5/(S8) bearer").
[0092] In a completely similar manner, in the down-link communication channel DWL a down-link
packet data traffic transport tunnel (bearer) can be defined, comprising:
- a first part of data traffic transport tunnel b3' between said at least one second
data traffic management gateway 9 (P-GW) and said at least one first data traffic
management gateway 7 (S-GW), defined therefore on the corresponding second interface
of the logic type I2 S5 for the transportation of data traffic (in the specification
3GPP TS 23.401, such part of transport tunnel is defined "S5/(S8) bearer");
- a second part of data traffic transport tunnel b2' between said at least one first
data traffic management gateway 7 (S-GW) and said at least one access network apparatus
eNodeB 3, defined therefore on the corresponding second interface of the logic type
I2 S1-U for the transportation of data traffic (in the specification 3GPP TS 23.401,
such part of transport tunnel is defined "S1-U bearer");
- a third part of data traffic transport tunnel b1', between said at least one access
network apparatus eNodeB 3 and said at least one User Equipment UE 1, therefore defined
on the interface of the radio IR LTE-Uu type (in the specification 3GPP TS 23.401,
such part of transport tunnel is defined "radio bearer").
[0093] It shall be noticed that in the lower portion of Fig. 2 and also in Fig. 3, the protocol
stack is illustrated relating to both the up-link communication channel UPL and the
down-link communication channel DWL.
[0094] It can be noticed that, in the up-link communication channel UPL, the first part
of transport tunnel b1 (radio bearer), the second part of transport tunnel b2 (S1-U
bearer) and the third part of transport tunnel b3 (S5 bearer) are concatenated together.
[0095] The communication protocol used for the data traffic transportation is GTP, from
the English acronym
GPRS Tunneling Protocol.
[0096] It is pointed out that, as stated above, the present invention refers to the management
of packet data traffic, therefore to the so-called transport tunnels (bearers) GTP-U
(
GTP-User plane), as indicated also in the specification 3GPP TS 29.281, which are necessary to allow
transporting packet data through the functional entities along the up-link communication
channel UPL and along the down-link communication channel DWL.
[0097] Now referring also to the Figs. 4-6, a method for managing transport tunnels (bearers)
of packet data services usable by a user in a LTE-technology telecommunication network
is now described, according to an embodiment of the present invention.
[0098] It shall be noticed that, in Fig. 4, the method for managing transport tunnels of
packet data services, herein below by the sake of brevity also management method,
or simply method, is generally indicated with the numeral reference 400.
[0099] It is pointed out that the LTE-technology telecommunications network within which
the management method 400 can be used can be, for example, the network architecture
100, described above, according to different embodiments.
[0100] Examples of packet data services exchanged with the packet data service network PDN
8 can be:
- voice service (for example, Conversational Voice);
- video service (for example, Conversational Video, Live Streaming);
- real-time time gaming service (for example, Real Time Gaming);
- non-real-time time gaming service (for example, Non-Conversational Video - Buffered Streaming);
- IMS signaling (for example, IMS Signalling);
- services based on TCP (for example, Video in Buffered Streaming TCP based - www., e-mail, chat, sharing, and so on).
[0101] In accordance with the specification 3GPP TS 23.203, each service is defined by determined
characteristics of quality of service (Quality of Service, QoS) having determined
values.
[0102] In more detail, the EPS level quality of service QoS is defined by an identifier
referred to as QCI, from the acronym
QoS (Quality of Service) Class Identifier, of the standard type.
[0103] To the purposes of the present description, by the phrase standard identifier QCI
is meant each of the identifiers QCI defined in the specification (standard) 3GPP
TS 23.203.
[0104] Each standard identifier QCI is a scalar value that, as defined according to the
regulations, hence to the specification or standard, may have nine different values,
1 to 9. Each standard identifier QCI is associated to a set service packet data usable
by a user.
[0105] The determined characteristics of quality of service to be ensured for a set packet
data service to which they are associated are associated to each standard identifier
QCI of a set packet data service.
[0106] The set characteristics of quality of service, for each packet data service, comprise:
- type of band available upon data transmission or resource type (Resource Type), i.e., the indication whether the data service transport tunnel to be used for a set
packet data service, in terms of propagation speed of the packet data, can be a guaranteed
band GBR (Guaranteed Bit Rate) or a non-guaranteed band Non-GBR (Non-Guaranteed Bit Rate);
- maximum delay allowed upon data transmission, PDB (Packet Delay Budget), for a set packet data service, expressed for example in milliseconds;
- maximum limit allowed of packet data loss upon data transmission, PELR (Packet Error Loss Rate), expressed as a non-dimensional number;
- priority level upon data transmission PRIO (Priority), i.e., the level of importance (or precedence) upon data transmission of the set
packet data service (to which a set priority level is associated), expressed by a
scalar value 1 to 9.
[0107] Therefore, in accordance with the specification 3GPP TS 23.203:
- one or more standard QCI identifiers can have guaranteed band GBR, other standard
QCI identifiers can have non-guaranteed band Non-GBR, assigned according to the set
packet data service to which they are associated;
- the standard QCI identifiers can have a maximum delay allowed upon data transmission
PDB (that may be different or the same one to another), assigned according to the
set service data to which they are associated;
- the standard QCI identifiers can have a maximum limit allowed of packet data loss
upon data transmission PELR (that may be different or the same one to another), assigned
according to the set packet data service to which they are associated;
- each standard identifier QCI may have a corresponding priority level upon data transmission
PRIO (different from that of the other standard QCI identifiers), assigned according
to the set packet data service to which it is associated.
[0108] From a logic viewpoint, the network architecture 100, for example, the scheduler
that is present in each of the functional entities eNodeB described above, is configured,
in hardware and/or in software, to allow, based on the specification 3GPP TS 23.203,
the management of the data traffic transport tunnels (bearers) in accordance with
the value of QCI standard associated to the packet data service required in the up-link
communication channel UPL from said at least one user equipment UE 1 to said packet
data service network PDN 8 and delivered in the down-link communication channel DWL
from said packet data service network PDN 8 to said at least one user equipment UE.
[0109] In fact, a standard QCI identifier is associated to each data traffic transport tunnel
(bearer) of one or more data services.
[0110] In order to solve the technical problem defined in the present description, the Applicant
noticed the possibility to aggregate types of different packet data services within
the same data traffic transport tunnel (bearer), defining proprietary QCI identifiers
representative of specific aggregated data service transport tunnel (aggregated QCI
identifiers).
[0111] To this aim, it shall be noticed that the technical specification 3GPP TS 23.203
defines the standard QCI identifiers (1-9) introduced above, but a plurality of values
(ranging between 128 and 254) is anyhow guaranteed, which values can be used for the
definition of so-called proprietary QCI identifiers, i.e., operator-specific QCI identifiers
(as set forth in the technical specification 3GPP TS 29.212).
[0112] This allows both associating standard QCI identifiers to packet data services, in
the case that such packet data services are intended to be transmitted on a pre-existing
network architecture the apparatuses of which are configured to manage data traffic
of packet data services only with standard QCI identifiers, and associating proprietary
QCI identifiers to packet data services, in the case that such packet data services
are intended to be transmitted on a network architecture the apparatuses of which
are configured to manage the data traffic of packet data services with proprietary
QCI identifiers.
[0113] Furthermore, also the possibility is allowed, to associate standard QCI identifiers
to some packet data services and proprietary QCI identifiers to other packet data
services. In this case, the network architecture on which such packet data services
can be transmitted comprises apparatuses configured to manage the data traffic of
packet data services both with standard QCI identifiers and with proprietary QCI identifiers.
[0114] At a general level, a proprietary QCI identifier represents the characteristics of
quality of service applied to a transport tunnel (bearer) for the traffic of packet
data services that are mutually aggregated, associated to a same proprietary QCI identifier.
[0115] To the purposes of the present description, a proprietary QCI identifier will be
indicated herein below also by the phrase aggregated QCI identifier.
[0116] In more detail, in the aggregated (proprietary) QCI identifier, each set characteristic
of quality of service to be ensured for the aggregated packet data services corresponds
to the set characteristic of quality of service selected among those individually
defined in the standard QCI identifiers for the packet data services which are now
aggregated.
[0117] The selection (hence, generally, aggregation) mode will be described in detail herein
below with particular reference to the method 400 in accordance with the present invention.
[0118] It is pointed out that the aggregation mode and the definition of proprietary QCI
identifiers proposed allows however to be in any case compliant to the specification
TS 23.203 and to be in line, therefore not in opposition, with the values defined
for the standard QCI identifiers, so as to allow, as stated above, to be able to transmit
the aggregated data services also on network architectures configured to manage the
traffic of packet data services with standard and/or proprietary QCI identifiers.
[0119] Referring back to the method 400 of Fig. 4, with reference also to the Fig. 5, the
method 400 comprises a symbolic step of starting ST.
[0120] The method 400 further comprises an step of identifying 401 a first packet data service
51 defined by a set first characteristic of quality of service 52 having a set first
value 53.
[0121] The first packet data service 51 can be, for example, a telephone voice service;
the set first characteristic 52 of the first packet data service 51 can be, for example,
the type of data transmission band; the set first value 53 of the set first characteristic
52 of the first packet data service 51 can be, for example, in the case of the telephone
voice service, guaranteed data transmission band GBR (Fig. 5).
[0122] The first packet data service 51 is further defined by at least one set second characteristic
of quality of service 54 having a corresponding second value 55.
[0123] The set second characteristic of quality of service 54 of the first packet data service
51 can be, in the embodiment of Figs. 4 and 5, the maximum delay allowed upon data
transmission PDB.
[0124] In other embodiments, the set second characteristic of quality of service 54 of the
first packet data service 51 can be the maximum limit allowed of packet data loss
upon data transmission PELR or the priority level upon data transmission PRIO.
[0125] Referring back to the Fig. 5, the corresponding second value 55 of the set second
characteristic of quality of service 54 is, for example, 100 ms (Fig. 5).
[0126] Referring back again to Fig. 4, the method 400 further comprises a step of identifying
402 at least one second packet data service 61 defined by a set further first characteristic
of quality of service 62 having a corresponding further first value 63.
[0127] The second packet data service 61 can be, for example, a real-time interactive service;
the set further first characteristic of quality of service 62 of the second data service
61 can be, for example, the type of data transmission band (Fig. 5).
[0128] In accordance with the embodiment of Fig. 5, the further first value 63 of the further
first characteristic of quality of service 62 of the second packet data service 61
is equal to the set first value 53 of the first characteristic of quality of service
52 of the first packet data service 61.
[0129] Such at least one second packet data service 61 is defined by at least one further
set second characteristic of quality of service 64 having a corresponding further
second value 65.
[0130] Said at least one further set second characteristic of quality of service 64 of the
second packet data service 61 is, in the embodiment of Figs. 4 and 5, the maximum
delay allowed upon data transmission PDB (Fig. 5).
[0131] In other embodiments, said at least one further set second characteristic of quality
of service 64 of the second packet data service 61 can be the maximum limit allowed
of packet data loss upon data transmission PELR or the priority level upon data transmission
PRIO.
[0132] The further second value 65 of said at least one further set second characteristic
of quality of service 64 of said at least one second packet data service 61 is different
from the set second value 55 of said second characteristic of quality of service 52
of the first packet data service 51.
[0133] For example, in the case that the second packet data service 61 is a real-time interactive
service, the further second value 65 of said at least one set second characteristic
of quality of service 64 is 50 ms (Fig. 5).
[0134] With reference again to Fig. 4, the method 400 further comprises a step of defining
403 an aggregate of packet data services 500, herein below also aggregate of data
service or simply aggregate, comprising the first packet data service 51 and said
at least one second packet data service 61.
[0135] Such aggregate of packet data services will be described herein below.
[0136] Next, the method 400 comprises a step of associating 404 the aggregate of packet
data services 500 with a transport tunnel (bearer) of packet data services. Examples
of transport tunnels of packet data service (EPS bearers b1-b3, b1'-b3') have been
defined above with particular reference to Fig. 2.
[0137] The method 400 further comprises a step of defining 405 an aggregated QCI identifier
representative of the transport tunnel associated to the aggregate of packet data
services 500.
[0138] As defined above, the aggregated QCI identifier is the proprietary QCI identifier
defined by the Applicant, as allowed by the standard 3GPP, which defines only the
so-called standard QCI identifiers.
[0139] A possible value of the aggregated QCI identifier for the aggregate of packet data
services 500 is, for example, 174.
[0140] Referring back to the step of defining 403 an aggregate of packet data services 500,
it is pointed out that the aggregate of packet data services 500 is defined by a first
aggregated characteristic of quality of service 501 having a corresponding first aggregated
value 502 and at least one second aggregated characteristic of quality of service
503 having a corresponding second aggregated value 504.
[0141] The first aggregated value 502 of the first aggregated characteristic of quality
of service 501 of the aggregate of packet data services 500 is the first value 53
of the first characteristic of quality of service 52 of the first packet data service
51.
[0142] The second aggregated value 503 of said at least one second aggregated characteristic
of quality of service 504 of the aggregate of packet data services 500, between the
second value 55 of said set second characteristic of quality of service 54 of the
first packet data service 51 and the further second value 65 of said at least one
further second characteristic of quality of service 64 of said at least one second
packet data service 61, is advantageously the one that is suitable to ensure the use
of both the first packet data service 51 and said at least one second packet data
service 61 both when the first packet data service 51 and said at least one second
packet data service 61 are transmitted within the aggregate of packet data services
500 and when the first packet data service 51 and said at least one second packet
data service 61 are transmitted individually within a corresponding transport tunnel
having a corresponding identifier QCI of the standard type.
[0143] In other terms, the selection between the second value 55 of said set second characteristic
of quality of service 54 of the first data service 51 and the further second value
65 of said at least one further second characteristic of quality of service 64 of
said at least one second packet data service 61 is aimed to select the one that is
suitable to ensure, on one hand, the use of both the first packet data service 51
and of said at least one second packet data service 61 when the first packet data
service 51 and said at least one second packet data service 61 are transmitted within
the aggregate of packet data services 500 and, on the other hand, without penalizing,
maintaining the characteristics, the single packet data services, as the first packet
data service 51 and said at least one second packet data service 61, when transmitted
individually, as defined by the standard, i.e., each within a corresponding transport
tunnel (bearer) having a corresponding identifier QCI of the standard type, i.e.,
defined in the specification 3GPP TS 23.203.
[0144] Such selection depends of course on the type of aggregated packet data services and
of the compared characteristic of quality of service in order to operate the selection.
[0145] In some cases, the selection may fall on the single value of the compared technical
characteristic that is equal for all the packet data services to be aggregated. For
example, if the compared technical characteristic is the type of data transmission
band, packet data services that are all in guaranteed band GBR or all in non-guaranteed
band Non-GBR are mutually aggregated.
[0146] In other cases, the selection may fall on the lowest value of the compared technical
characteristic on the packet data services to be aggregated. For example, if the compared
technical characteristic is the maximum delay allowed upon data transmission, then
the selection falls on the lowest value.
[0147] In still other cases, the selection may fall on the highest value of the compared
technical characteristic on the packet data services to be aggregated. For example,
if the compared technical characteristic is the maximum delay allowed upon data transmission
PDB, the maximum limit allowed of packet data loss upon data transmission PELR, or
the priority level upon data transmission PRIO (the importance level), then the selection
may fall on the lowest value, except for some cases.
[0148] In fact, in still other cases, the selection may fall on the lowest value of the
compared technical characteristic on the packet data services to be aggregated, in
the case that the latter is the priority level upon data transmission PRIO. In fact,
in the case that a penalization of an aggregate of packet data services (or single
packet data services with standard QCI) with a higher importance (for example relating
to packet data services of the voice type) is not desired, a possible and further
aggregate of packet data services could be defined with an aggregated characteristic
of quality of data service, such as the priority level upon data transmission, having
a value corresponding to the highest or any other value different from the lowest
among the values of compared technical characteristics.
[0149] This allows respecting a determined hierarchic order among aggregates of packet data
services and single packet data services with standard QCI identifier, such as not
to penalize the most important packet data services.
[0150] Such aspect will be reaffirmed herein below with particular reference to a further
aggregate of packet data services, indicated with the numeral reference 600, obtainable
with the method 400 in accordance with the embodiment of Figs. 4 and 5.
[0151] Referring back to Fig. 5, the first aggregated characteristic of quality of service
501 is the type of band available upon data transmission (GBR, Non-GBR); the corresponding
first aggregated value 502 of the first aggregated characteristic of quality of service
501 is, for example, available guaranteed data transmission band (GBR); said at least
one second aggregated characteristic of quality of service 503 is the maximum delay
allowed upon data transmission PDB and the corresponding second aggregated value 504
of said at least one second aggregated characteristic of quality of service 503 is
50 ms.
[0152] It shall be noticed that, in this embodiment, the selection in order to determine
said at least one second aggregated characteristic of quality of service 503 (maximum
delay allowed upon data transmission PDB) has fallen on the lowest among the compared
values.
[0153] The method 400 comprises a symbolic step ending ED.
[0154] In accordance with an embodiment of the method 400, the first packet data service
51 is defined by at least one third characteristic of quality of service 56 having
a corresponding third value 57.
[0155] With reference to Fig. 5, the third characteristic of quality of service 56 is, in
an embodiment, the maximum limit allowed of packet data loss upon data transmission
PELR.
[0156] In accordance with a further embodiment, the third characteristic of quality of service
56 can be the priority level upon data transmission PRIO.
[0157] The corresponding third value 57 of the third characteristic of quality of service
56 of the first packet data service, in the case that such third characteristic is
the maximum limit allowed of packet data loss upon data transmission PELR, is, for
example, 10
-2.
[0158] In accordance again with this embodiment, said at least one second data service 61
is defined by at least one further third characteristic of quality of service 66 having
a corresponding further third value 67.
[0159] With reference to Fig. 5, the at least one further third characteristic of quality
of service 66 is the maximum limit allowed of packet data loss upon data transmission
PELR; the corresponding third value 67 of said at least one third characteristic of
quality of service 505 is 10
-3 ms.
[0160] The aggregate of packet data services 500 is further defined by a third aggregated
characteristic of quality of service 505 having a corresponding third aggregated value
506.
[0161] The third aggregated value 506 of said at least one third aggregated characteristic
of quality of service 505 of the aggregate of packet data services 500, between the
third value 57 of said determined second characteristic of quality of service 56 of
the first packet data service 51 and the further third value 67 of said at least one
further third characteristic of quality of service 66 of said at least one second
packet data service 61, is advantageously the one that is suitable to ensure the use
of both the first packet data service 51 and of said at least one second packet data
service 61 both when the first packet data service 51 and said at least one second
packet data service 61 are transmitted within the aggregate of packet data services
500 and when the first packet data service 51 and said at least one second packet
data service 61 are transmitted individually within a corresponding transport tunnel
(bearer) having a corresponding identifier QCI of the standard type.
[0162] In other terms, also in this embodiment, the selection in the step of defining the
aggregate of packet data services 500 is aimed to select the value suitable to ensure,
on one hand, the use of both the first packet data service 51 and of said at least
one second packet data service 61 when the first packet data service 51 and said at
least one second packet data service 61 are transmitted within the aggregate of packet
data services 500 and, on the other hand, without penalizing, preserving the characteristics
thereof, the single packet data services, as the first packet data service 51 and
said at least one second packet data service 61, when transmitted individually, as
defined by the standard, i.e., each within a corresponding transport tunnel (bearer)
having a corresponding QCI identifier of the standard type, i.e., defined in the specification
3GPP TS 23.203.
[0163] With reference to Fig. 5, the third aggregated characteristic of quality of service
505 is the maximum limit allowed of packet data loss upon data transmission PELR;
the corresponding third aggregated value 506 of the third aggregated characteristic
of quality of service 505 is 10
-3.
[0164] It shall be noticed that, in this embodiment, the selection in order to determine
said at least one third aggregated characteristic of quality of service 505 (maximum
limit allowed of packet data loss upon data transmission PELR) has fallen on the lowest
among the compared values.
[0165] The method 400 ends with a step of ending ED.
[0166] In accordance with another embodiment, the first packet data service 51 is defined
by at least one fourth characteristic of quality of service 58 having a corresponding
fourth value 59.
[0167] With reference to Fig. 5, said at least one fourth characteristic of quality of service
58 of the first packet data service 51 is the priority level upon data transmission
PRIO. The corresponding fourth value 59 of said at least one fourth characteristic
of quality of service 58 of the first packet data service 51 is the scalar value 2.
[0168] It shall be noticed that, in accordance with the specification 3GPP TS 23.203, the
scalar value representative of the priority level upon data transmission PRIO is inversely
proportional to the priority level upon data transmission PRIO of the packet data
service to which that scalar value is assigned.
[0169] In other terms, with reference to the figure, the packet data service to which a
scalar value 9 is associated of priority level upon data transmission PRIO is the
packet data service with the lowest priority, while the packet data service to which
a scalar value 1 is associated of priority level upon data transmission PRIO is the
packet data service with the highest priority.
[0170] Referring back to the embodiment, said at least one second packet data service 61
is defined by at least one further fourth characteristic of quality of service 68
having a corresponding further fourth value 69.
[0171] With reference to the embodiment of Fig. 5, said at least one further fourth characteristic
of quality of service 68 is, in this embodiment, the priority level upon data transmission
PRIO.
[0172] The corresponding further fourth value 69 of said at least one further fourth characteristic
of quality of service 68 of the second packet data service 61 is the scalar value
3.
[0173] The aggregate of packet data services 500 is defined by a fourth aggregated characteristic
of quality of service 507 having a corresponding fourth aggregated value 508.
[0174] The fourth aggregated value 508 of said at least one fourth aggregated characteristic
of quality of service 507 of the aggregate of packet data services 500, between the
fourth value 59 of the fourth characteristic of quality of service 58 of the first
packet data service 51 and the further fourth value 69 of the further fourth characteristic
of quality of service 68 of said at least one second packet data service 61, is advantageously
the one that is suitable to ensure the use of both the first packet data service 51
and of said at least one second packet data service 61 both when the first packet
data service 51 and said at least one second packet data service 61 are transmitted
within the aggregate of packet data services 500 and when the first data service 51
and said at least one second data service 61 are transmitted individually within a
corresponding transport tunnel (bearer) having a corresponding QCI identifier of the
standard type.
[0175] In other terms, also in this embodiment, the selection in the step of defining the
aggregate of packet data services 500 is aimed to select the value suitable to ensure,
on one hand, the use of both the first packet data service 51 and of said at least
one second packet data service 61 when the first packet data service 51 and said at
least one second packet data service 61 are transmitted within the aggregate of packet
data services 500 and, on the other hand, without penalizing, preserving the characteristics
thereof, the single packet data services, as the first packet data service 51 and
said at least one second packet data service 61, when transmitted individually, as
defined by the standard, i.e., each within a corresponding transport tunnel (bearer)
having a corresponding QCI identifier of the standard type, i.e., defined in the specification
3GPP TS 23.203.
[0176] With reference still to Fig. 5, the fourth aggregated characteristic of quality of
service 507 is the priority level upon data transmission PRIO; the corresponding fourth
aggregated value 508 of the fourth aggregated characteristic of quality of service
507 is 2.
[0177] It shall be noticed that, in this embodiment, the selection in order to determine
said at least one fourth aggregated characteristic of quality of service 507 (priority
level upon data transmission PRIO) has fallen on the lowest among the compared values.
[0178] In accordance with a further embodiment, illustrated also in Fig. 4 with hatched
lines, the method 400 further comprises a step of identifying 406 of at least one
third packet data service 71 defined by a further first characteristic of quality
of service 72 having a corresponding further first value 73, said further first value
73 being equal to the determined first value 53 of the first characteristic of quality
of service 52 of the first packet data service 51.
[0179] With reference to Fig. 5, said at least one third packet data service 71 is a Live
Streaming video service.
[0180] The further first characteristic of quality of service 72 of said at least one third
packet data service 71 is the type of band available upon data transmission.
[0181] The further first value 73 of the further first characteristic of quality of service
72 of said at least one third packet data service 71 is available guaranteed data
transmission band GBR.
[0182] The at least one third packet data service 71 is defined by at least one further
second characteristic of quality of service 74 having a corresponding further second
value 75, the further second value 75 of said at least one further second characteristic
of quality of service 74 of said at least one third packet data service 71 is different
from at least one of the second value 55 of said second characteristic of quality
of service 54 of the first packet data service 51 and the further second value 65
of said at least one further second characteristic of quality of service 64 of said
at least one second packet data service 61.
[0183] It shall be noticed that also the at least one third packet data service 71 is defined
by at least one further third characteristic of quality of service 76 and by at least
one further fourth characteristic of quality of service 78 (Fig. 5). Examples of such
characteristics of quality of service will be described herein below.
[0184] With reference to Fig. 5, if the maximum delay allowed upon data transmission PDB
is considered as said at least one further second characteristic of quality of service
74 of the third packet data service 71, its corresponding second value 75 is 150 ms,
different from both the corresponding second value 55 of the second characteristic
of quality of service 54 of the first packet data service 51, i.e., 100 ms, and the
corresponding second value 65 of the second characteristic of quality of service 64
of the second packet data service 61, i.e., 50 ms.
[0185] The method 400 further comprises a step of associating 407, to the aggregate of packet
data services 500 of the first packet data service 51 and of said at least one second
packet data service 61, said at least one third packet data service 71.
[0186] The first aggregated value 502 of said first characteristic of quality of service
501 of the aggregate of packet data services 500 is the first value 53 of the first
characteristic of quality of service 52 of the first packet data service 51 (i.e.,
GBR).
[0187] The second aggregated value 504 of said at least one second aggregated characteristic
503, between the second value 55 of the second characteristic of quality of service
54 of the first packet data service 51 (i.e., 100 ms), the further second value 65
of the further second characteristic of quality of service 64 of said at least one
second packet data service 61 (i.e., 50 ms) and the further second value 75 of the
further second characteristic of quality of service 74 of the third packet data service
71 (i.e., 150 ms), is advantageously the one that is suitable to ensure the use of
the first packet data service 51, of said at least one second packet data service
61 and of said at least one third packet data service 71, both when the first packet
data service 51, said at least one second packet data service 61 and said at least
one third packet data service 71 are transmitted within the aggregate of packet data
services 500, and when the first packet data service 51, said at least one second
packet data service 61 and said at least one third packet data service 71 are transmitted
individually within a corresponding transport tunnel (bearer) having a corresponding
QCI identifier of the standard type.
[0188] In other terms, the selection in the step of defining the aggregate of packet data
services 500 is aimed to select the value suitable to ensure, on one hand, the use
of the first packet data service 51, of said at least one second packet data service
61 and of said at least one third packet data service 71 when the first packet data
service 51, said at least one second packet data service 61 and said at least one
third packet data service 71 are transmitted within the aggregate of packet data services
500 and, on the other hand, without penalizing, preserving the characteristics thereof,
the single packet data services, as the first packet data service 51, said at least
one second packet data service 61 and said at least one third packet data service
71 when transmitted individually, as defined by the standard, i.e., each within a
corresponding transport tunnel (bearer) having a corresponding QCI identifier of the
standard type, i.e., defined in the specification 3GPP TS 23.203.
[0189] In an embodiment, the first characteristic of quality of service 52 of the first
packet data service 51, the further first characteristic of quality of service 62
of said at least one second packet data service 61 and the further first characteristic
of quality of service 72 of said at least one third packet data service 71 are the
type of band available upon data transmission.
[0190] In the embodiment of Fig. 5, such type of band available upon data transmission,
for the first packet data service 51, said at least one second packet data service
61 and said at least one third packet data service 71, is guaranteed (GBR).
[0191] The selection of the first aggregated value 502 of said first characteristic of quality
of service 501 of the aggregate of packet data services 500 has therefore fallen on
a type of available guaranteed data transmission band (GBR).
[0192] Furthermore, in this embodiment, it is reaffirmed that the second characteristic
of quality of service 54 of the first packet data service 51, the further second characteristic
of quality of service 64 of said at least one second data service 61 and the further
second characteristic of quality of service 74 of said at least one third packet data
service 71 are the maximum delay allowed upon data transmission PDB for the data service
to which it is assigned.
[0193] It shall be noticed that, in this embodiment, the selection of the second aggregated
value 504 of said at least one second aggregated characteristic of quality of service
503 (maximum delay allowed upon data transmission PDB) has fallen on the lowest among
the compared values (50ms).
[0194] In addition, again in the same embodiment, it is reaffirmed that the third characteristic
of quality of service 56 of the first data service 51, the further third characteristic
of quality of service 66 of said at least one second data service 61 and the further
third characteristic of quality of service 76 of said at least one third data service
71 are the maximum limit allowed of packet data loss upon data transmission PELR allowed
for the data service to which it is assigned.
[0195] It shall be noticed that in this embodiment, the selection of the third aggregated
value 506 of said at least one third aggregated characteristic of quality of service
505 (maximum limit allowed of packet data loss upon data transmission PELR), carried
out according to the same criterion indicated for the selection of the second aggregated
value 504 of said at least one second aggregated characteristic of quality of service
503 (not repeated herein by the sake of brevity), has fallen on the lowest among the
compared values (10
-3).
[0196] Still, again in the same embodiment, the fourth characteristic of quality of service
58 of the first data service 51, the further fourth characteristic of quality of service
68 of said at least one second data service 61 and the further fourth characteristic
of quality of service 78 of said at least one third packet data service 71 are the
priority level upon data transmission PRIO of the data service to which it is assigned.
[0197] It shall be noticed that, in this embodiment, the selection of the fourth aggregated
value 508 of said at least one fourth aggregated characteristic of quality of service
507 (priority level upon data transmission PRIO), carried out according to the same
criterion indicated for the selection of the second aggregated value 504 of said at
least one second aggregated characteristic of quality of service 503 (not repeated
herein by the sake of brevity), has fallen on the lowest among the compared values
(2).
[0198] It is pointed out that the embodiment of Fig. 5, besides the aggregate of packet
data services 500, illustrates other aggregates of packet data services, obtainable
with the management method 400 described above.
[0199] In more detail, in Fig. 5, it is noticed that, in accordance with the management
method 400 of the present invention, it has been possible to aggregate, besides the
first three packet data services, corresponding to the standard QCI identifiers of
value 1, 2 and 3, respectively, (aggregate of packet data services 500), the further
packet data services corresponding, respectively, to the standard QCI identifiers
6, 8 and 9 in a further aggregate of packet data services indicated with the numeral
reference 600.
[0200] Therefore, all the steps of the method 400 indicated above to obtain the aggregate
of packet data services 500 can be repeated also for the definition of the further
aggregate of packet data services 600.
[0201] With reference to Fig. 5, in the aggregate of packet data services 600, the first
packet data service can be considered as the one with the assigned standard QCI identifier
of value 6; said at least one second packet data service can be considered as the
one with the assigned standard QCI identifier of value 8; said at least one third
packet data service can be considered as the one with the assigned QCI identifier
of value 9.
[0202] Each of these services of the type packet data are defined by a first characteristic
of quality of service (for example, the type of band available upon data transmission),
a second characteristic of quality of service (for example, the maximum delay allowed
upon data transmission PDB), a third characteristic of quality of service (for example,
the maximum limit allowed of packet data loss upon data transmission PELR), a fourth
characteristic of quality of service (for example, the priority level upon data transmission
PRIO).
[0203] In accordance with the embodiment of Fig. 5, such packet data services are of the
Video/TCP based type and have in common the same value of type of band available upon
data transmission (non-guaranteed, Non-GBR), the same maximum delay allowed upon data
transmission PDB (300ms), the same maximum limit allowed of packet data loss upon
data transmission PELR (10
-6).
[0204] Therefore, by applying the same selection criterion already defined above, the further
aggregate of packet data services 600 is defined by: a first aggregated characteristic
of quality of service 601 having a first aggregated value 602, corresponding to the
type of non-guaranteed band available upon data transmission Non-GBR; a second aggregated
characteristic of quality of service 603 having a second aggregated value 604, corresponding
to PDB = 300ms; a third aggregated characteristic of quality of service 605 having
a third aggregated value 606, corresponding to PELR = 10
-6.
[0205] The further aggregate of packet data services 600 is further defined by a fourth
aggregated characteristic of quality of service 607 having a fourth aggregated value
608, corresponding to PRIO = 9.
[0206] It shall be noticed that, in this embodiment, the selection of the fourth aggregated
value 608 of said at least one fourth aggregated characteristic of quality of service
607 (maximum limit allowed of packet data loss upon data transmission PELR), carried
out according to the same criterion indicated for the definition of the aggregate
of packet data services 500 (not repeated herein by the sake of brevity), has fallen
on the highest among the compared values (9).
[0207] Such selection allows advantageously assigning to the further aggregate of packet
data services 600 a priority level such as to allow, on one hand, the use of the above-mentioned
packet data services both when transmitted in the further aggregate of packet data
services 600 and, on the other hand, without penalizing the same data services when
transmitted individually with an assigned QCI identifier of the standard type or another
aggregate of packet data services (for example, the aggregate of packet data services
500), with an assigned aggregated QCI identifier, having a aggregated characteristic
of quality of service of a lower value, in the case of the priority level upon data
transmission PRIO, compared to the corresponding aggregated characteristic (for example
the fourth one, as indicated above) of the further aggregate of packet data services
600.
[0208] In other terms, such selection allows not penalizing packet data services not being
part of the further aggregate of packet data services 600 to which ensure a scheduling
priority is desired to be ensured, favoring the performance characteristics thereof,
that is anyhow higher than the one of the further aggregate of packet data services
600.
[0209] It shall be noticed that what has been indicated for the further aggregate of packet
data services 600 can be applied also in the definition of the aggregate of packet
data services 500.
[0210] Referring back to the embodiment of Fig. 5, it shall be noticed that, on the contrary,
it has been preferred to not aggregated two or more of the data services corresponding,
respectively, to the standard QCI identifiers of value 4, 5 and 7 that, therefore,
remain represented and defined individually.
[0211] This is due to the fact that the aggregation in accordance with the management method
400 would have imposed to some packet data services characteristics of quality of
service that would not have allowed being compliant with the specifications required
by the standard TS 23.203 for that type of packet data service.
[0212] In this regard, an aggregated QCI identifier is defined also for the further aggregate
of packet data services 600, as for the aggregate of packet data services 500. The
other data services, which are not aggregated with any other data service, will maintain
the standard QCI identifier.
[0213] A possible value of the aggregated QCI identifier for the further aggregate of packet
data services 600 is, for example, 136.
[0214] The possible value of the aggregated QCI identifier for the aggregate of packet data
services 500 is, instead, as defined above, for example, 174.
[0215] Therefore, by the management method 400 of the present invention, it was possible
to decrease the number of data service transport tunnels (bearers) (in the described
example, from 9 to 5).
[0216] It shall be noticed that in the last row of the table illustrated in Fig. 5, the
five ones among the aggregates of packet data services (EPS bearers)/single EPS bearers
(not aggregated) are indicated, defined with the management method 400 of the present
invention, each indicated with the corresponding characteristics of quality of service.
[0217] With reference also generally to the method for managing transport tunnels of data
service, it shall be noticed that, as illustrated in the figures 1 and 2, when a quality
of service level is defined (aggregate of packet data services with aggregated QCI
identifiers), such definition applies within the LTE-technology network architecture,
i.e., on the uplink communication channel UPL between said at least one user equipment
UE 1 and said packet data traffic management network EPC 4 and on the downlink communication
channel DWL from said packet data traffic management network EPC 4 and said at least
one user equipment UE 1.
[0218] However, the improvements of the management of the data traffic made at the level
of quality of service for the aggregated transportation as described above, do not
have any impact upon forwarding the packet data at the level of the transportation
network IP. In fact, unless specifically defined, the transportation of packet data
on the transportation networks IP occurs in the best-effort mode for all the requests
of all users, independently from the defined and/or assigned quality of service.
[0219] In order to obviate this drawback, the Applicant proposed, in addition to the aggregation
of the transport tunnels (bearers), as described above, so as to decrease the number
thereof, the mapping of each aggregate of packet data services with a numeral value
representative of the priority level of such aggregate of packet data services at
the level of the transportation network IP.
[0220] Therefore, a mapping (i.e., routing) rule was defined between the quality of the
service QoS defined at the LTE level (aggregated QCI identifiers and standard, i.e.,
not aggregated QCI identifiers,) and a quality of service at the level of the transportation
network IP.
[0221] For the definition of such mapping rule, reference can be made to the so-called architecture
of
Differentiated Services, usually used for the network architectures at the IP level on a large scale, as defined
in the publication IETF RFC 4594 (
Internet Engineering Task Force Request For Comments 4594).
[0222] This type of architecture allows the association or mapping (so-called coloration)
of a IP data packet with a predetermined scalar numeral value (color) as a function
of which a corresponding service class is identified.
[0223] By service class is meant a type of packet data services that, in terms of quality
of service, at the level of IP transportation network, need to undergo to the same
processing.
[0224] For example, packets that are mapped (or colored) in the same manner refer to a same
type of packet data service (for example, voice) and, during the transportation on
the IP level transportation network, each network node, based on the numerical value
(coloration) associated to the packet, is capable of defining the IP-level priority
to be associated to such data packet.
[0225] Therefore, the mapping or coloration is set on both the apparatuses of the network
architecture 100 in LTE technology and on all the apparatuses of the I P transportation
network, which entities are used for the routing of the data packets, i.e., the apparatuses
of the so-called transportation clouds based on the IP (IP-based) transportation,
not shown in the figures.
[0226] The mapping or coloration (to be inserted in the "traffic service" field of the heading
of the packet IP) defines a differentiation at the service level, which allows managing
the priority routing of the data traffic also in the case of a network congestion.
[0227] In fact, the only scheduling priorities defined on the LTE technology network architecture,
without the addition of the mapping or coloration defined above at the IP level, would
not be of help in the case of network congestion problems. In this regard, if such
a transportation mechanism (mapping or coloration at the IP level) would not be able
to be added, the IP transportation network would be dimensioned with a so high capacity
to ensure the maximum available band required by all the service types.
[0228] Therefore, in an embodiment, the method for managing transport tunnels according
to the invention, comprises both the aggregation of packet data services within the
transport tunnel (QCI identifier) and the embedding of such transport tunnel (routing,
mapping or coloration at the IP level) in a IP packet that can be routed, by the network
nodes of the IP transportation network, as a function of a IP-level priority decided
based on a service class.
[0229] Based on what has been stated above, referring now to Fig. 4, in accordance with
an embodiment (shown in hatched lines), the method 400 further comprises a step of
associating 408 to each data service a corresponding numeral value DSCP (Differentiated
Services Code Point) representative of the priority level of such data service upon
data transmission at the IP transportation network level.
[0230] It shall be noticed that in the embodiment of Fig. 5, a corresponding numeral value
DSCP D1, for example EF, is associated to the first packet data service 51. A corresponding
numeral value DSCP D2, for example AF4X, is associated to said at least one second
packet data service 61. A corresponding numeral value D3, for example CS4, is associated
to said at least one third packet data service 71
[0231] The method 400 then ends with a step of ending E.
[0232] Furthermore, in accordance with a further embodiment, illustrated in hatched lines
in Fig. 4, in the case that the first packet data service 51, with an associated corresponding
first numeral value DSCP D1 representative of the IP-level priority level of such
first packet data service 51 upon data transmission at the IP transportation network
level, and said at least one second data service 61, with an associated second numeral
value DSCP D3 representative of the IP-level priority level of said at least one second
data service 61 upon data transmission at the IP transportation network level, are
aggregated in the aggregate of packet data services 500, the method 400 comprises
a step of associating 409 to the aggregate of packet data services 500 a corresponding
aggregated numeral value DSCP DA1 representative of the IP-level priority level of
such aggregate of packet data services upon data transmission at the IP transportation
network level, selected between said first numeral value DSCP D1 representative of
the IP-level priority level of such first data service 51 upon data transmission at
the IP transportation network level and said second numeral value DSCP D2 representative
of the IP-level priority level of said at least one second data service 61 upon data
transmission at the IP transportation network level.
[0233] The selection is based on the fact that to each of the packet data services, thus
with an aggregated (proprietary) QCI identifier, a numeral value DSCP is associated,
which is suitable to ensure the best data transmission performance within the aggregate
of packet data services 500, therefore also to the packet data service which, among
those aggregated within the aggregate of packet data services 500, need a higher performance.
[0234] With reference to the table of Fig. 5, the first two row correspond to the mapping
or coloration at the IP transportation level with the mapping architecture DSCP. The
second row sets forth the association of a numeral value DSCP (color) to each data
service set forth in the table; the first row sets forth instead the association of
an aggregated numeral value DSCP (color) to each aggregate of determined packet data
services.
[0235] As it shall be noticed, the aggregate of packet data services 500 has a mapping DSCP
= EF (indicated in the first row), corresponding to the mapping of the first packet
data service 51, i.e., the voice service (indicated in the second row).
[0236] The further aggregate of packet data services 600 has a mapping DSCP = CS1 (indicated
in the first row), corresponding to the mapping of the service relating to TCP-protocol-based
applications that does not require band guarantees, CS1.
[0237] The decision to use the mapping value CS1 with priority level upon data transmission
PRIO that is typically processed with a standard data transmission processing is to
limit the effect of loss of packets at the IP level which are a part of the further
aggregate of packet data services 600, relating to TCP-protocol-based applications.
[0238] The method 400 ends, also in this case, with a symbolic step of ending E.
[0239] In accordance with a further embodiment of the management method of the present invention,
the Applicant considered a further parameter of quality of service, referred to as
ARP (
Allocation Retention Priority).
[0240] The parameter is the result of a further aggregation mechanism used on LTE technology
architectures.
[0241] In more detail, it shall be noticed that during the data traffic management, thus
also of the data traffic transport tunnels, different parameters of quality of service
(QoS) are exchanged, for example QoS parameters depending on the user profile (for
the default transport tunnel) or next QoS parameters depending on the service types
that the user is requiring to the service network PDN. Such parameters correspond
to the QCI identifier (which is described above) and, precisely, the parameter ARP.
[0242] The parameter ARP comprises a numeral value (scalar value) of allocation priority
level ARP, associated to a request of transport tunnel (bearer) to be able to allow
applying management mechanisms of the data traffic network congestion.
[0243] In case of a service request, the network is informed of the need of having a transport
tunnel (bearer) with a specific QCI identifier (this can be one of the nine standard
QCI identifiers or one of the aggregated - proprietary QCI identifiers defined for
the aggregates of data services).
[0244] In response to the request, a transport tunnel (bearer) with determined characteristics
is obtained. However, there is no guarantee to be able to obtain in response always
the same resources. In fact, if a fault or a congestion problem occurs in the network,
the new incoming requests are not accepted (there is even the risk that some already
assigned services are terminated).
[0245] For the management also of these terminations, the data traffic management mechanism
based on the parameter ARP is used.
[0246] If a service request is made by a user at a priority level ARP that is higher than
other users, in lack radio resources, the scheduler of an eNodeB serves first the
request with a higher priority level ARP.
[0247] It shall be noticed that the priority level ARP is based on the user profile type
or it can be based on the service type. In the second case, the level of the parameter
ARP that is used is different while the service is the same.
[0248] Instead, for different services, also the same priority level ARP can be present,
however, in this moment, all would be managed in concurrence, by the scheduler of
an eNodeB, with the priority of the QCI, therefore the resource management would be
implemented on a still different level.
[0249] Also with the same service type, the fact of defining a parameter ARP with a higher
priority ensures preempting the data service transport tunnel (bearer) with a lower
parameter ARP and passing the transport tunnel (bearer) with the highest parameter
ARP, in the case that there are no sufficient resources.
[0250] As described in the technical specification 3GPP TS 23.203, to the priority level
ARP parameter (numeral value 1 to 15) other two Boolean values (YES, NO) are associated:
a second value representative of the pre-emption capability in the case of a conflict;
a third value representative of the pre-emption vulnerability in the case of a conflict.
[0251] For example, an operator of the commercial network (in the case he/she wants to reach
a network apparatus for maintenance operations) may enter with a request with a high
priority level ARP parameter, defining the second value and the third value so as
to pre-empt all the other ones, while not being subjected to a pre-emption.
[0252] In Fig. 6 is illustrated a table that shows the priority level ARP parameter (numerical
value), the second Boolean value and the third Boolean value defined for the aggregate
of packet data services 500 and the further aggregate of packet data services 600
illustrated in Fig. 5.
[0253] Referring back to Fig. 4, the method 400 comprises, in accordance with a further
embodiment (shown in the figures in hatched lines), a step of associating 410 to said
at least one aggregate of packet data services 500 (or said further aggregate of packet
data services 600) a corresponding value of allocation priority level ARP of such
aggregate of packet data services 500 (or said further aggregate of packet data services
600) at the radio level.
[0254] In addition, the method 400 comprises a step of associating 411 to said at least
one aggregate of packet data services 500 (or said further aggregate of packet data
services 600), with the associated value of allocation priority level ARP of such
aggregate of packet data services 500 (or said further aggregate of packet data services
600) at the radio level, a second Boolean value representative of the pre-emption
capability of such aggregate of packet data services 500 (or said further aggregate
of packet data services 600) with respect to a further aggregate of packet data services
or a data service individually transmitted within a corresponding transport tunnel
(bearer) having a corresponding QCI identifier of the standard type, with an associated
corresponding value of allocation priority level (ARP) of such further aggregate of
packet data services or of the data service individually transmitted within a corresponding
transport tunnel (bearer) having a corresponding QCI identifier of the standard type
upon data transmission at the radio level, lower than the value of allocation priority
level ARP associated to such at least one aggregate of packet data services 500 (or
said further aggregate of packet data services 600) at the radio level.
[0255] In addition, the method 400 comprises a step of associating 412 to said at least
one aggregate of packet data services 500 (or said further aggregate of packet data
services 600), with the associated value of allocation priority level ARP of such
aggregate of packet data services 500 (or said further aggregate of packet data services
600) at the radio level, a third Boolean value representative of the pre-emption vulnerability
of such aggregate of packet data services 500 (or said further aggregate of packet
data services 600) during the transmission in the case that a further aggregate of
packet data services or a packet data service individually transmitted within a corresponding
transport tunnel (bearer) having a corresponding QCI identifier of the standard type
is present, with an associated corresponding value of allocation priority level ARP
of such further aggregate of packet data services or a packet data service individually
transmitted within a corresponding transport tunnel (bearer) having a corresponding
QCI identifier of the standard type upon data transmission at the radio level that
is higher than the priority level allocation value ARP associated to such at least
one aggregate of packet data services 500 (or said further aggregate of packet data
services 600) at the radio level.
[0256] The method 400 ends with a symbolic step of ending E.
[0257] As already indicated also above, it is pointed out that the method for managing transport
tunnels of packet data services, in accordance with any embodiment, can be applied
to the functional entities of the LTE technology network architecture 100 corresponding
to the network apparatuses (nodes) of the IP transportation network (IP-based network)
specially configured in hardware and/or in software.
[0258] As it can be noticed, the proposed method for managing data transport tunnels (bearers)
has several advantages.
[0259] In fact, by defining a management method that aggregates, where possible, one or
more different data services in a transport tunnel (bearer) (GTP-U, Evolved Packet
System (EPS) Bearer), it is possible to obtain a decrease of the number of transport
tunnels required for the data traffic transportation (
user pl
ane), thus improving the overall performance of the LTE-technology telecommunications
network, in particular, the packet data traffic management network EPC (
Evolved Packet Core).
[0260] Furthermore, in addition to a performance improvement, it is possible to define a
convergent processing of the quality of service between the LTE protocol and the IP-level
network transportation by means of the Differentiated Services architecture.
[0261] With the proposed method for managing data transport tunnels, it is possible to improve
the performance of the data traffic management network EPC without necessarily making
modifications to the standard, i.e., proposing an aggregation model of the data services
that has characteristics of quality of service (QoS) homogeneous and applicable not
only to the LTE architecture, but also to the IP-level transportation network (IP-based
network).
[0262] Based on the technical specification 3GPP TS 23.203, the proposed method allows maintaining
the interoperability with the standardized products of other LTE operators.
[0263] Furthermore, it is reaffirmed that the method of the invention allows reducing the
number of transport tunnels (bearers) GTP-U by decreasing the times of data traffic
management by the EPC network, thus improving the overall performance of the network
architecture.
[0264] Still, the treatment of the quality of service by aggregating multiple packet data
services in one transport tunnel (bearer) EPS, based on a combination of the values
of the standardized QoS parameters (QCI) in the specification 3GPP TS 23.203, allows
maintaining the interoperability with operators compliant with the standard.
[0265] The mapping between the aggregated (proprietary) QCI identifier or the standard (non-aggregated)
QCI identifier that identifies the quality of service QoS at the transport tunnel
(EPS bearer) level and the corresponding IP-level service class, by assigning a numeral
value (coloration) of DSCP in the corresponding field of the header of the IP packet
transporting the user data plus the tunnel GTP-U header, advantageously allows obtaining
a priority level defined also in the routing between the IP-level transportation network
nodes.
[0266] The definition and use of the parameter ARP associated to the aggregates of packet
data services allows managing at the best network congestion conditions.
[0267] The above-mentioned performance advantages are more apparent in the case of networks
that are congested by a high number of users requiring multiple services that are
mutually heterogeneous.
[0268] Finally, it shall be noticed that the proposed method may find a use in commercial
products in which it is possible to require a quality of service QCI identifier for
which the values of the QoS parameters defined in the proposal can be configured (to
date, the technical specifications 3GPP provides for such possibility, which is however
left vendor-dependent).