(19)
(11)EP 2 919 444 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
26.04.2017 Bulletin 2017/17

(21)Application number: 13865100.5

(22)Date of filing:  19.12.2013
(51)International Patent Classification (IPC): 
H04L 29/12(2006.01)
(86)International application number:
PCT/CN2013/089968
(87)International publication number:
WO 2014/094633 (26.06.2014 Gazette  2014/26)

(54)

METHOD, RELAY DEVICE, AND SYSTEM FOR ACQUIRING INTERNET PROTOCOL ADDRESS IN NETWORK

VERFAHREN, RELAISVORRICHTUNG UND SYSTEM ZUR ERFASSUNG VON INTERNETPROTOKOLLADRESSEN IN EINEM NETZWERK

PROCÉDÉ, DISPOSITIF RELAIS, ET SYSTÈME POUR ACQUÉRIR UNE ADRESSE IP DANS UN RÉSEAU


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 19.12.2012 CN 201210553582

(43)Date of publication of application:
16.09.2015 Bulletin 2015/38

(60)Divisional application:
17152756.7

(73)Proprietor: Huawei Technologies Co., Ltd.
Longgang District Shenzhen, Guangdong 518129 (CN)

(72)Inventors:
  • HE, Qingtao
    Shenzhen Guangdong 518129 (CN)
  • LI, Yong
    Shenzhen Guangdong 518129 (CN)
  • KE, Bo
    Shenzhen Guangdong 518129 (CN)

(74)Representative: Thun, Clemens 
Mitscherlich PartmbB Patent- und Rechtsanwälte Sonnenstraße 33
80331 München
80331 München (DE)


(56)References cited: : 
CN-A- 1 949 784
CN-A- 102 404 418
CN-A- 101 534 329
US-B1- 6 587 468
  
  • Anonymous: "Understanding relay agents: Dynamic Host Configuration Protocol (DHCP)", , 21 January 2005 (2005-01-21), pages 1-2, XP055242067, Retrieved from the Internet: URL:https://technet.microsoft.com/en-us/li brary/cc779610(v=ws.10).aspx [retrieved on 2016-01-15]
  • HORI K ET AL: "AUTOMATIC CONFIGURATION METHOD FOR IP ROUTERS IN DYNAMICALLY CHANGING NETWORK", ELECTRONICS & COMMUNICATIONS IN JAPAN, PART I - COMMUNICATIONS, WILEY, HOBOKEN, NJ, US, vol. 89, no. 5, PART 01, 1 May 2006 (2006-05-01), pages 15-27, XP001240135, ISSN: 8756-6621, DOI: 10.1002/ECJA.20247
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

TECHNICAL FIELD



[0001] The present invention relates to the communications field, and in particular, to a method, a relay agent, and a system for acquiring an IP address in a network.

BACKGROUND



[0002] The Dynamic Host Configuration Protocol (Dynamic Host Configuration Protocol, DHCP) is a dynamic address allocation solution based on the TCP/IP protocol. Compared with manual configuration of an IP address, the DHCP has advantages, for example, TCP/IP parameters (including an IP address, a subnet mask, a default gateway, a DNS, and the like) can be automatically configured, and an allocated IP address has a lease time and can be reclaimed for reuse after the lease time expires. In this way, all configuration information of the TCP/IP protocol may be stored on a DHCP server in a centralized manner. Centralized storage and management can prevent an IP address conflict, and can also free an administrator from burdensome manual configuration work. The advantages of the DHCP are becoming more prominent when a network scale at present is becoming larger.

[0003] Because the DHCP protocol needs to use a broadcast request to configure an IP address, this leads to a limitation that a DHCP client and the DHCP server need to be in a same physical network segment, where each physical network segment needs one DHCP server. If the DHCP client and the DHCP server are not in the same physical network segment, the DHCP client needs to use a DHCP relay agent (DHCP Relay Agent, DHCP relay agent) to acquire an IP address from the DHCP server that is in a different physical network segment. A network device with a DHCP relay function may receive a DHCP request packet and forward the DHCP request packet to a DHCP server in another physical network segment; in this case, the DHCP server can perform corresponding configuration for a DHCP client in a different physical network segment. Therefore, by using a DHCP relay agent, a limitation that each physical network segment needs one DHCP server may be lifted.

[0004] Currently, implementation of a DHCP relay agent is as follows: a DHCP client type is differentiated according to an OPTION60 or a MAC address in a DHCP request packet, and one DHCP gateway IP address is allocated to one DHCP client type. Therefore, an existing DHCP relay agent cannot be implemented in a case in which different network segments need to be allocated to a same client type, for example, two types of DHCP clients have a same OPTION60, but a DHCP server needs to allocate, according to their different area locations or different types of services provided by them, IP addresses in different network segments to the two types of DHCP clients.
CN 1 949 784 A discloses a method for Dynamic Host Configuration Protocol (DHCP) relay to request an IP address for a DHCP client, the method further comprises: A, the DHCP relay agent receives a request message sent by a DHCP client by broadcast, and adds gateway IP addresses or network segment addresses to the configuration request message and then sends the message to DHCP server; B, the DHCP server determines the gateway IP address or network segment address of the subnetwork the DHCP client belongs to, by the added gateway IP address or network segment address in the request message, and allocates an IP address in a corresponding address pool to the determined gateway IP address or network segment address to the DHCP client and transmits the allocated IP address through the DHCP relay to the DHCP client. The method only requires the DHCP relay and DHCP server make one communication interaction in the course that the DHCP client obtains dynamic allocated IP address by DHCP relay, saving time and raising efficiency.
Anonymous: "Understanding relay agents: Dynamic Host Configuration Protocol (DHCP)", 21 January 2005(2005-01-21), pages 1-2, XP055242067, discloses the relay agent, in this case a DHCP/BOOTP relay-enabled router, examines the gateway IP address field in the DHCP/BOOTP message header. If the field has an IP address of 0.0.0.0, the agent fills it with the relay agent or router's IP address and forwards the message to the remote Subnet 1, where the DHCP server is located. When DHCP server 1 on remote Subnet 1 receives the message, it examines the gateway IP address field for a DHCP scope that can be used by the DHCP server to supply an IP address lease. If DHCP server 1 has multiple DHCP scopes, the address in the gateway IP address field (GIADDR) identifies the DHCP scope from which to offer an IP address lease. For example, if the gateway IP address (GIADDR) field has an IP address of 10.0.0.2, the DHCP server checks its available set of address scopes for a scope range of addresses that matches the class A IP network that includes the gateway address as a host. In this case, the DHCP server would make a check for a scope of addresses between 10.0.0.1 and 10.0.0.254. If a matching scope exists, the DHCP server selects an available address from the matched scope to use in an IP address lease offer response to the client. When DHCP server 1 receives the DHCPDISCOVER message, it processes and sends an IP address lease offer (DHCPOFFER) directly to the relay agent identified in the gateway IP address (GIADDR) field. The router then relays the address lease offer (DHCPOFFER) to the DHCP client.

SUMMARY



[0005] Embodiments of the present invention are intended to provide a method, relay agent, and system for acquiring an IP address in a network, which can implement that multiple IPs in different IP address segments are allocated to a same DHCP client type.

[0006] According to a first aspect, a method for acquiring an Internet Protocol (IP)address in a network is provided, where the network includes a client, a relay agent, and a Dynamic Host Configuration Protocol (DHCP) server, the client is connected to the DHCP server via the relay agent, multiple gateway IP addresses corresponding to a type of the client are configured in the relay agent, and the method includes:

receiving, by the relay agent, the DHCP Discover packet from the client, replicating the DHCP Discover packet to obtain multiple DHCP Discover packets, adding one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet, and sending the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address, or

receiving multiple DHCP Discover packets of the client, sequentially adding the multiple gateway IP addresses to the multiple DHCP Discover packets, and sending the multiple DHCP Discover packets to the DHCP server, where each DHCP Discover packet carries one different gateway IP address, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; and

the method further includes:

receiving, by the relay agent, a DHCP Request packet from the client, and acquiring the IP address of the client from an Option 50 field or a ciaddr field of DHCP Request packet; and

adding, by the relay agent to the DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sending the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client.



[0007] With reference to the first aspect, in a first possible implementation manner of the first aspect, before the adding, by the relay agent, the multiple gateway IP addresses to a DHCP Discover packet of the client, and sending the DHCP Discover packet to the DHCP server, the method further comprises:

acquiring, by the relay agent, the type of the client and the multiple gateway IP addresses corresponding to the type of the client according to the type of the client.



[0008] According to a second aspect, a relay agent includes:

a user-side port, configured to connect to a client, and configured to receive a Dynamic Host Configuration Protocol DHCP Discover packet of the client;

a memory, configured to store multiple gateway IP addresses corresponding to a type of the client;

a network-side port, configured to connect to a DHCP server;

a first processor, that comprises an adding module, configured to add the multiple gateway IP addresses to multiple DHCP Discover packets received by the user-side port, and add one gateway IP address to each DHCP discover packet; and a sending module, configured to send the multiple DHCP Discover packets with the gateway IP addresses to the DHCP server by using the network-side port, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; or

the first processor comprises a replicating module, configured to replicate the DHCP Discover packet to obtain multiple DHCP Discover packets; an adding module, configured to add one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet; and a sending module, configured to send the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server by using the network-side port, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; and

the relay agent further comprises a second processor, configured to: after a DHCP Request packet from the client is received by the user-side port, acquire the IP address of the client from an Option 50 field or a ciaddr field of DHCP Request packet, select, from the multiple gateway IP addresses, one gateway IP address that belongs to the same network segment as the IP address of the client, add the selected gateway IP address to the DHCP Request packet, and send the DHCP Request packet to the DHCP server, so that the DHCP server allocates the IP address to the client.



[0009] With reference to the second aspect, in a first possible implementation manner of the second aspect, the relay agent is a digital subscriber line access multiplexer DSLAM, an optical line terminal OLT, or a multiservice access node MSAN.

[0010] According to a third aspect, a system for acquiring an Internet Protocol IP includes: a client, a relay agent, and a Dynamic Host Configuration Protocol DHCP server, where the client is connected to the DHCP server via the relay agent;
the relay agent, configured with multiple gateway IP addresses corresponding to a type of the client,
the relay agent, configured to receive the DHCP Discover packet from the client, replicate the DHCP Discover packet to obtain multiple DHCP Discover packets, add one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet, and send the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server; or
the relay agent, configured to receive multiple DHCP Discover packets of the client, sequentially add the multiple gateway IP addresses to the multiple DHCP Discover packets, and send the multiple DHCP Discover packets to the DHCP server, wherein each DHCP Discover packet carries one different gateway IP address;
the relay agent, further configured to receive a DHCP Request packet from the client, acquire an IP address of the client from an Option 50 field or a ciaddr field of DHCP Request packet, select, from the multiple gateway IP addresses, one gateway IP address that belongs to a same network segment as the IP address of the client, add the selected gateway IP address to the DHCP Request packet, and send the DHCP Request packet to the DHCP server, so that the DHCP server allocates the IP address to the client; and
the DHCP server is configured to: after receiving the DHCP Discover packet, allocate the IP address to the client, and send a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to the same network segment as the allocated IP address.

[0011] With reference to the third aspect, in a first possible implementation manner of the third aspect, the relay agent is further configured to: after receiving the DHCP Discover packet of the client, acquire the type of the client, and acquire the multiple corresponding gateway IP addresses according to the type of the client.

[0012] With reference to the third aspect, or the first possible implementation manner of the third aspect, in a second possible implementation manner of the third aspect, the relay agent is a digital subscriber line access multiplexer, DSLAM, an optical line terminal, OLT, or a multiservice access node, MSAN.

[0013] Compared with the prior art, embodiments of the present invention provide a method for acquiring an IP address in a network, and according to the method, a relay agent configures multiple gateway IP addresses corresponding to a type of a client; the relay agent adds the multiple gateway IP addresses to a DHCP Discover packet of the client, and sends the DHCP Discover packet to a DHCP server, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; the relay agent adds, to a DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sends the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client. In this way, it is implemented that multiple IPs in different IP address segments are allocated to a same DHCP client type.

BRIEF DESCRIPTION OF DRAWINGS



[0014] To describe the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings required for describing the embodiments. Apparently, the accompanying drawings in the following description show merely some embodiments of the present invention, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

FIG. 1 is a flowchart of a method for acquiring an IP address in a network according to Embodiment 1 of the present invention;

FIG. 2 is a schematic diagram of a method for acquiring an IP address in a network according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a method for acquiring an IP address in a network according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a method for acquiring an IP address in a network according to an embodiment of the present invention;

FIG. 5 is an apparatus structural diagram of a relay agent according to Embodiment 2 of the present invention;

FIG. 6 is an apparatus structural diagram of a first processor in a relay agent according to Embodiment 2 of the present invention;

FIG. 7 is an apparatus structural diagram of a first processor in a relay agent according to Embodiment 2 of the present invention;

FIG. 8 is a structural diagram of a system for acquiring an Internet Protocol IP according to Embodiment 3 of the present invention; and

FIG. 9 is an apparatus structural diagram of a relay agent according to Embodiment 4 of the present invention.


DESCRIPTION OF EXAMPLES



[0015] To make the objectives, technical solutions, and advantages of the present invention clearer and more comprehensible, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific described herein are merely used to explain the present invention but are not intended to limit the present invention.

[0016] The foregoing descriptions are merely exemplary embodiments of the present invention, but are not intended to limit the present invention.

Example 1



[0017] Referring to FIG. 1, FIG. 1 is a flowchart of a method for acquiring an IP address in a network according to Example 1 of the present invention. As shown in FIG. 1, the method includes the following steps:

Step 101. A relay agent adds multiple gateway IP addresses to a DHCP Discover packet of a client, and sends the DHCP Discover packet to a DHCP server, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address.



[0018] Realizably, before that a relay agent adds multiple gateway IP addresses to a DHCP Discover packet of a client, and sends the DHCP Discover packet to a DHCP server, the method further includes:

acquiring a type of the client, and acquiring multiple corresponding gateway IP addresses according to the type of the client.



[0019] In this step, the DHCP relay agent learns a gateway IP address automatically, that is, the DHCP relay agent configures multiple gateway IP addresses for a same DHCP client type.

[0020] Realizably, that a relay agent adds multiple gateway IP addresses to a DHCP Discover packet of a client, and sends the DHCP Discover packet to a DHCP server specifically includes:

receiving the DHCP Discover packet from the client, replicating the DHCP Discover packet to obtain multiple DHCP Discover packets, adding one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet, and sending the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server.



[0021] In this step, the DHCP Discover packet is the first packet when the DHCP client starts a DHCP procedure, and the DHCP client sends the DHCP Discover packet to the DHCP server, so as to request the DHCP server to configure a correct IP address for the DHCP client.

[0022] Realizably, that a relay agent adds multiple gateway IP addresses to a DHCP Discover packet of a client, and sends the DHCP Discover packet to a DHCP server specifically includes:

receiving multiple DHCP Discover packets of the client, sequentially adding the multiple gateway IP addresses to the multiple DHCP Discover packets, and sending the multiple DHCP Discover packets to the DHCP server, where each DHCP Discover packet carries one different gateway IP address.



[0023] Step 102. The relay agent receives a DHCP Request packet from the client, and acquires the IP address of the client from the DHCP Request packet.

[0024] Realizably, the acquiring the IP address of the client from the DHCP Request packet specifically includes:

acquiring the IP address of the client from an Option 50 field or a ciaddr field of the DHCP Request packet.



[0025] In this step, the DHCP relay agent finds, in the multiple gateway IP addresses and according to the Option 50 field or the ciaddr field of the DHCP Request packet sent by the client, the gateway IP address that belongs to the same network segment as the DHCP client.

[0026] Step 103. The relay agent adds, to the DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sends the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client.

[0027] Specifically, referring to FIG. 2, FIG. 2 is a schematic diagram of a method for acquiring an IP address in a network according to this example of the present invention. FIG. 2 includes the following steps:

Step 201. A DHCP client sends a DHCP Discover packet to a DHCP server; a DHCP relay agent receives the DHCP Discover packet, fills the first gateway IP address in multiple pre-allocated gateway IP addresses into a gateway IP address of the DHCP Discover packet, and sends the DHCP Discover packet filled with the gateway IP address to the DHCP server; the DHCP server pre-allocates an IP address in a correct IP network segment to the DHCP client according to a related characteristic in the DHCP Discover packet, and checks whether the pre-allocated IP address and the gateway IP address filled into the DHCP Discover packet belong to a same network segment.

Step 202. If the pre-allocated IP address and the gateway IP address filled into the DHCP Discover packet do not belong to the same network segment, the DHCP server considers the DHCP Discover packet invalid, releases the pre-allocated IP, and no longer sends a DHCP Offer packet to the DHCP client; after that, a state machine of the DHCP client expires, and a DHCP Discover packet is sent again; after receiving the second DHCP Discover packet sent by the DHCP client, the DHCP relay agent selects the second gateway IP address, fills the gateway IP address into a gateway IP address of the second DHCP Discover packet, and sends the second DHCP Discover packet filled with the gateway IP address to the DHCP server. By that analogy, a one-by-one test manner is used until a correct gateway IP address is selected for the DHCP Discover packet.

Step 203. If the pre-allocated IP address and the gateway IP address filled into the DHCP Discover packet belong to the same network segment, the DHCP server sends a DHCP Offer packet to the DHCP client.

Step 204. After receiving the DHCP Offer packet, the DHCP client sends a DHCP Request packet to the DHCP server; the DHCP relay agent finds, in the multiple gateway IP addresses and according to a related characteristic in the DHCP Request packet, a gateway IP address that belongs to a same network segment as the DHCP client, fills the gateway IP address into a gateway IP address of the DHCP Request packet, and sends the DHCP Request packet filled with the gateway IP address to the DHCP server.

Step 205. The DHCP server receives the DHCP Request packet filled with the gateway IP address, and responds to the DHCP client with a DHCP ACK packet, so that the DHCP client acquires the IP address in the correct IP network segment according to the DHCP ACK packet.



[0028] In an optional example, the method further includes:

[0029] If the pre-allocated IP address and the gateway IP address filled into the DHCP Discover packet do not belong to the same network segment, confirming, by the DHCP server, that the DHCP Discover packet is invalid, releasing the pre-allocated IP address in the correct IP network segment, and skipping sending a DHCP Offer packet to the DHCP client.

[0030] After that, a state machine of the DHCP client expires, and a Discover packet is sent to the DHCP server again; when receiving the DHCP Discover packet sent by the DHCP client again, the DHCP relay agent selects a next gateway IP address in the multiple gateway IP addresses, fills the gateway IP address into a gateway IP address of the DHCP Discover packet sent again, and sends the DHCP Discover packet filled with the gateway IP address to the DHCP server; the DHCP server receives the DHCP Discover packet filled with the gateway IP address, pre-allocates an IP address in a correct IP network segment to the DHCP client according to a related characteristic of the DHCP Discover packet, and determines whether the pre-allocated IP address and the gateway IP address filled into the DHCP Discover packet belong to a same network segment.

[0031] Specifically, referring to FIG. 3, FIG. 3 is a schematic diagram of a method for acquiring an IP address in a network according to this example of the present invention. FIG. 3 includes the following steps:

Step 301. A DHCP client sends a DHCP Discover packet to a DHCP server; a DHCP relay agent receives the DHCP Discover packet, replicates the DHCP Discover packet to obtain multiple DHCP Discover packets, adds one gateway IP address in multiple gateway IP addresses to each DHCP Discover packet, and sends the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server.

Step 302. The DHCP server receives the multiple DHCP Discover packets filled with gateway IP addresses, pre-allocates an IP address in a correct IP network segment to the DHCP client according to a related characteristic in the multiple DHCP Discover packets, determines whether the pre-allocated IP address and one of the gateway IP addresses filled into the multiple DHCP Discover packets belong to a same network segment, and responds, with a DHCP Offer packet, to a DHCP Discover packet filled with the gateway IP address that belongs to the same network segment.



[0032] In this step, after receiving the multiple DHCP Discover packets filled with the gateway IP addresses, the DHCP server pre-allocates the IP address in the correct IP network segment to the DHCP client according to OPTION60s or MAC addresses of the multiple DHCP Discover packets, determines whether the pre-allocated IP address and one of the gateway IP addresses filled into the multiple DHCP Discover packets belong to the same network segment, and responds, with the DHCP Offer packet, to the DHCP Discover packet that belongs to the same network segment.

[0033] The DHCP Offer packet is a response made by the DHCP server to the DHCP Discover packet.

[0034] Step 303. After receiving the DHCP Offer packet, the DHCP client sends a DHCP Request packet to the DHCP server; the DHCP relay agent finds, in the multiple gateway IP addresses and according to a related characteristic in the DHCP Request packet, a gateway IP address that belongs to a same network segment as the DHCP client, fills the gateway IP address into a gateway IP address of the DHCP Request packet, and sends the DHCP Request packet filled with the gateway IP address to the DHCP server.

[0035] The DHCP Request packet is a response made by the DHCP client to the DHCP Offer packet of the DHCP server when the DHCP client starts a DHCP procedure, or a packet sent by the DHCP client to extend an IP address lease time.

[0036] In this step, the DHCP relay agent finds, in the multiple gateway IP addresses and according to the IP address of the DHCP client in the DHCP Request packet, namely, an Option 50 field or a ciaddr field of the DHCP Request packet, the gateway IP address that belongs to the same network segment as the DHCP client, fills the gateway IP address into the gateway IP address of the DHCP Request packet, and sends the DHCP Request packet filled with the gateway IP address to the DHCP server.

[0037] Step 304. The DHCP server receives the DHCP Request packet filled with the gateway IP address, and responds to the DHCP client with a DHCP ACK packet, so that the DHCP client acquires the IP address in the correct IP network segment according to the DHCP ACK packet.

[0038] The DHCP ACK packet is an acknowledgement response packet made by the DHCP server to the DHCP Request packet of the DHCP client. After receiving this packet, the DHCP client generally starts a new DHCP procedure.

[0039] In this step, the DHCP server receives the DHCP Request packet filled with the gateway IP address, and responds to the DHCP client with the DHCP ACK packet, so that the DHCP client acquires the IP address in the correct IP network segment according to the DHCP ACK packet, thereby completing the procedure of acquiring the IP address by the DHCP client.

[0040] In another optional example, referring to FIG. 4, FIG. 4 is a schematic diagram of a method for acquiring an IP address in a network according to this example of the present invention.

[0041] After a DHCP client completes an IP address acquiring procedure, when 50% of a lease time remains, the DHCP client sends a unicast DHCP Request packet to a DHCP server; if the DHCP server responds to the DHCP Request packet, the DHCP server sends a DHCP ACK packet to the DHCP client, so as to confirm that the packet is valid and confirm that the DHCP client can continue to use a current allocated IP address.

[0042] When the unicast DHCP Request packet fails to be received and 87.5% of the lease time remains, the DHCP client sends a broadcast DHCP Request packet to the DHCP server; after receiving the broadcast DHCP Request packet, a DHCP relay agent fills, according to a ciaddr field of the DHCP Request packet, a correct gateway IP address into a gateway IP address of the DHCP Request packet. After receiving the DHCP Request packet filled with the gateway IP address, the DHCP server responds to the DHCP client with a DHCP ACK packet, and the DHCP client acquires a correct IP address according to the DHCP ACK packet, thereby completing the procedure of acquiring the IP address by the DHCP client.

[0043] This example of the present invention provides a method for acquiring an IP address in a network. According to the method, a relay agent configures multiple gateway IP addresses corresponding to a type of a client; the relay agent adds the multiple gateway IP addresses to a DHCP Discover packet of the client, and sends the DHCP Discover packet to a DHCP server, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; the relay agent adds, to a DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sends the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client, thereby implementing that multiple IPs in different IP address segments are allocated to a same DHCP client type.

[0044] In this example, for lease renewal of a DHCP client, a DHCP relay agent is not required for unicast renewal; for a broadcast renewal packet, the DHCP client learns a ciaddr field of a DHCP Request packet, and fills a correct gateway IP address. In this way, by using the method for acquiring an IP address in a network, the DHCP client can acquire a correct IP address no matter during a normal IP address acquiring procedure or a lease renewal procedure.

Example 2



[0045] Referring to FIG. 5, FIG. 5 is an apparatus structural diagram of a relay agent according to Example 2 of the present invention. As shown in FIG. 5, the apparatus includes the following devices:

a user-side port 501, configured to connect to a client, and configured to receive a Dynamic Host Configuration Protocol DHCP Discover packet of the client;

a memory 502, configured to store multiple gateway IP addresses corresponding to a type of the client;

a network-side port 503, configured to connect to a DHCP server; and

a first processor 504, configured to add the multiple gateway IP addresses to the DHCP Discover packet of the client, and send the DHCP Discover packet to the DHCP server by using the network-side port, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address.



[0046] Realizably, the first processor 504 specifically includes:

a replicating module 601, configured to replicate the DHCP Discover packet to obtain multiple DHCP Discover packets;

an adding module 602, configured to add one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet; and

a sending module 603, configured to send the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server by using the network-side port.



[0047] Realizably, the first processor 504 specifically includes:

an adding module 701, configured to add the multiple gateway IP addresses to multiple DHCP Discover packets received by the user-side port, where one gateway IP address is added to each DHCP discover packet;

a sending module 702, configured to send the multiple DHCP Discover packets with the gateway IP addresses to the DHCP server; and

a second processor 505, configured to: after a DHCP Request packet from the client is received by the user-side port, acquire an IP address of the client from the DHCP Request packet, select, from the multiple gateway IP addresses, one gateway IP address that belongs to the same network segment as the IP address of the client, add the selected gateway IP address to the DHCP Request packet, and send the DHCP Request packet to the DHCP server, so that the DHCP server allocates the IP address to the client.



[0048] Realizably, the second processor specifically acquires the IP address of the client from an Option 50 field or a ciaddr field of the DHCP Request packet.

[0049] The relay agent is a digital subscriber line access multiplexer DSLAM, an optical line terminal OLT, or a multiservice access node MSAN.

[0050] This example of the present invention provides a relay agent. The relay agent configures multiple gateway IP addresses corresponding to a type of a client; the relay agent adds the multiple gateway IP addresses to a DHCP Discover packet of the client, and sends the DHCP Discover packet to a DHCP server, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; the relay agent adds, to a DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sends the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client, thereby implementing that multiple IPs in different IP address segments are allocated to a same DHCP client type.

Example 3



[0051] Referring to FIG. 8, FIG. 8 is a structural diagram of a system for acquiring an Internet Protocol IP according to Example 3 of the present invention. As shown in FIG. 8, the system includes the following apparatuses:

a client, a relay agent, and a Dynamic Host Configuration Protocol DHCP server, where the client is connected to the DHCP server via the relay agent.



[0052] The relay agent, configured with multiple gateway gateway IP addresses corresponding to a type of the client, adds the multiple gateway IP addresses to a DHCP Discover packet of the client, and sends the DHCP Discover packet to the DHCP server; receives a DHCP Request packet from the client, acquires an IP address of the client from the DHCP Request packet, selects, from the multiple gateway IP addresses, one gateway IP address that belongs to a same network segment as the IP address of the client, adds the selected gateway IP address to the DHCP Request packet, and sends the DHCP Request packet to the DHCP server, so that the DHCP server allocates the IP address to the client.

[0053] Realizably, that the relay agent adds the multiple gateway IP addresses to a DHCP Discover packet of the client, and sends the DHCP Discover packet to the DHCP server specifically includes:

receiving the DHCP Discover packet from the client, replicating the DHCP Discover packet to obtain multiple DHCP Discover packets, adding one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet, and sending, to the DHCP server, the multiple DHCP Discover packets carrying different gateway IP addresses.



[0054] Realizably, that the relay agent adds the multiple gateway IP addresses to a DHCP Discover packet of the client, and sends the DHCP Discover packet to the DHCP server specifically includes:

receiving multiple DHCP Discover packets of the client, sequentially adding the multiple gateway IP addresses to the multiple DHCP Discover packets, and sending the multiple DHCP Discover packets to the DHCP server, where each DHCP Discover packet carries one different gateway IP address.



[0055] The DHCP server is configured to: after receiving the DHCP Discover packet, allocate the IP address to the client, and send a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to the same network segment as the allocated IP address.

[0056] In an optional example, the relay agent is further configured to: after receiving the DHCP Discover packet of the client, acquire the type of the client, and acquire the multiple corresponding gateway IP addresses according to the type of the client.

[0057] This example of the present invention provides a system. The system configures multiple gateway IP addresses corresponding to a type of a client by using a relay agent; the relay agent adds the multiple gateway IP addresses to a DHCP Discover packet of the client, and sends the DHCP Discover packet to a DHCP server, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; the relay agent adds, to a DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sends the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client, thereby implementing that multiple IPs in different IP address segments are allocated to a same DHCP client type.

Example 4



[0058] Referring to FIG. 9, FIG. 9 is an apparatus structural diagram of a relay agent according to Example 4 of the present invention. Referring to FIG. 9, FIG. 9 shows a relay agent 900 according to this embodiment of the present invention. A specific example of the present invention does not limit a specific implementation of the communications device. The relay agent 900 includes:

a processor (processor) 901, a chip 902, a memory (memory) 903, and a bus 904, where

the processor 901, the chip 902, and the memory 903 complete communication with each other by using the bus 904;

the chip 902 is configured to communicate with a DHCP server; and

the processor 901 is configured to execute a program.



[0059] Specifically, the program may include program code, where the program code includes a computer operation instruction.

[0060] The processor 901 may be one or more central processing units CPU, or an application-specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the example of the present invention.

[0061] The memory 903 is configured to store the program. The memory 903 may include a high-speed random access memory (random access memory, RAM for short), or may further include a non-volatile memory (non-volatile memory).

[0062] When the relay agent is running, the processor 901 is configured to execute the program.

[0063] The relay agent adds multiple gateway IP addresses to a DHCP Discover packet of a client, and sends the DHCP Discover packet to a DHCP server, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address;
the relay agent receives a DHCP Request packet from the client, and acquires the IP address of the client from the DHCP Request packet; and
the relay agent adds, to the DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sends the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client.

[0064] A person of ordinary skill in the art may understand that all or some of the processes of the methods in the embodiments of the present invention may be implemented by a computer program instructing relevant hardware. The program may be stored in a computer readable storage medium. When the program runs, the processes of the methods in the embodiments are performed. The storage medium may include: a magnetic disk, an optical disc, a read-only memory (Read-Only Memory, ROM), or a random access memory (Random Access Memory, RAM).

[0065] The foregoing descriptions are merely exemplary embodiments of the present invention, but are not intended to limit the protection scope of the present invention.


Claims

1. A method for acquiring an Internet Protocol, IP, address in a network, wherein the network comprises a client, a relay agent, and a Dynamic Host Configuration Protocol, DHCP, server, the client is connected to the DHCP server via the relay agent, multiple gateway IP addresses corresponding to a type of the client are configured in the relay agent, and the method being characterized by:

receiving (101), by the relay agent, the DHCP Discover packet from the client, replicating the DHCP Discover packet to obtain multiple DHCP Discover packets, adding one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet, and sending the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; or

receiving (101), by the relay agent, multiple DHCP Discover packets of the client, sequentially adding the multiple gateway IP addresses to the multiple DHCP Discover packets, and sending the multiple DHCP Discover packets to the DHCP server, wherein each DHCP Discover packet carries one different gateway IP address, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; and

the method further comprises:

receiving (102), by the relay agent, a DHCP Request packet from the client, and acquiring the IP address of the client from an Option 50 field or a ciaddr field of DHCP Request packet; and

adding (103), by the relay agent to the DHCP Request packet, the gateway IP address that is in the multiple gateway IP addresses and belongs to the same network segment as the IP address of the client, and sending the DHCP Request packet with the gateway IP address to the DHCP server, so that the DHCP server allocates the IP address to the client.


 
2. The method according to claim 1, before the adding, by the relay agent, the multiple gateway IP addresses to a DHCP Discover packet of the client, and sending the DHCP Discover packet to the DHCP server, the method further comprises:

acquiring, by the relay agent, the type of the client and the multiple gateway IP addresses corresponding the type of the client according to the type of the client.


 
3. A relay agent for acquiring an Internet Protocol, IP, address, comprising:

a user-side port (501), configured to connect to a client, and configured to receive a Dynamic Host Configuration Protocol, DHCP, Discover packet of the client;

a memory (502), configured to store multiple gateway IP addresses corresponding to a type of the client;

a network-side port (503), configured to connect to a DHCP server;

characterized by

a first processor (504), that comprises an adding module (701), configured to add the multiple gateway IP addresses to multiple DHCP Discover packets received by the user-side port, and add one gateway IP address to each DHCP discover packet; and a sending module (702), configured to send the multiple DHCP Discover packets with the gateway IP addresses to the DHCP server by using the network-side port, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; or,

the first processor comprises a replicating module (601), configured to replicate the DHCP Discover packet to obtain multiple DHCP Discover packets; an adding module (602), configured to add one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet; and a sending module (603), configured to send the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server by using the network-side port, so that the DHCP server allocates an IP address to the client, and sends a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to a same network segment as the allocated IP address; and

the relay agent further comprises a second processor (505), configured to: acquire the IP address of the client from an Option 50 field or a ciaddr field of DHCP Request packet after a DHCP Request packet from the client is received by the user-side port, select, from the multiple gateway IP addresses, one gateway IP address that belongs to the same network segment as the IP address of the client, add the selected gateway IP address to the DHCP Request packet, and send the DHCP Request packet to the DHCP server, so that the DHCP server allocates the IP address to the client.


 
4. The device according to claim 3, wherein the relay agent is a digital subscriber line access multiplexer, DSLAM, an optical line terminal, OLT, or a multiservice access node, MSAN.
 
5. A system for acquiring an Internet Protocol IP address, comprising a client, a relay agent, and a Dynamic Host Configuration Protocol DHCP server, wherein the client is connected to the DHCP server via the relay agent; wherein the relay agent, configured with multiple gateway IP addresses corresponding to a type of the client,
characterized by
the relay agent, configured to receive the DHCP Discover packet from the client, replicate the DHCP Discover packet to obtain multiple DHCP Discover packets, add one gateway IP address in the multiple gateway IP addresses to each DHCP Discover packet, and send the multiple DHCP Discover packets carrying different gateway IP addresses to the DHCP server; or
the relay agent, configured to receive multiple DHCP Discover packets of the client, sequentially add the multiple gateway IP addresses to the multiple DHCP Discover packets, and send the multiple DHCP Discover packets to the DHCP server, wherein each DHCP Discover packet carries one different gateway IP address;
the relay agent, further configured to receive a DHCP Request packet from the client, acquire an IP address of the client from an Option 50 field or a ciaddr field of DHCP Request packet, select, from the multiple gateway IP addresses, one gateway IP address that belongs to a same network segment as the IP address of the client, add the selected gateway IP address to the DHCP Request packet, and send the DHCP Request packet to the DHCP server, so that the DHCP server allocates the IP address to the client; and
the DHCP server, configured to allocate the IP address to the client after receiving the DHCP Discover packet, and send a DHCP Offer packet to the client after determining that one gateway IP address in the multiple gateway IP addresses belongs to the same network segment as the allocated IP address.
 
6. The system according to claim 5, wherein the relay agent is further configured to:

acquire the type of the client and the multiple gateway IP addresses corresponding the type of the client according to the type of the client after receiving the DHCP Discover packet of the client.


 
7. The system according to any one of claims 5 to 6, wherein the relay agent is a digital subscriber line access multiplexer, DSLAM, an optical line terminal, OLT, or a multiservice access node, MSAN.
 


Ansprüche

1. Verfahren zum Erfassen einer Internetprotokoll-Adresse, IP-Adresse, in einem Netz, wobei das Netz einen Client, einen Relaisagenten und einen Server des dynamischen Hostkonfigurationsprotokolls, DHCP-Server, umfasst, der Client über den Relaisagenten mit dem DHCP-Server verbunden ist, mehrere Gateway-IP-Adressen, die einem Typ des Client entsprechen, in dem Relaisagenten konfiguriert sind und das Verfahren gekennzeichnet ist durch:

Empfangen (101) durch den Relaisagenten des DHCP-Findepakets von dem Client, Replizieren des DHCP-Findepakets, um mehrere DHCP-Findepakete zu erhalten, Hinzufügen einer Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu jedem DHCP-Findepaket und Senden der mehreren DHCP-Findepakete, die unterschiedliche Gateway-IP-Adressen führen, zu dem DHCP-Server, so dass der DHCP-Server dem Client eine IP-Adresse zuweist und ein DHCP-Angebotspaket zu dem Client sendet nach dem Bestimmen, dass eine Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu demselben Netzsegment wie die zugewiesene IP-Adresse gehört; oder

Empfangen (101) durch den Relaisagenten von mehreren DHCP-Findepaketen des Client, sequenzielles Hinzufügen der mehreren Gateway-IP-Adressen zu den mehreren DHCP-Findepaketen und Senden der mehreren DHCP-Findepakete zu dem DHCP-Server, wobei jedes DHCP-Findepaket eine unterschiedliche Gateway-IP-Adresse führt, so dass der DHCP-Server eine IP-Adresse dem Client zuweist und ein DHCP-Angebotspaket zu dem Client sendet nach dem Bestimmen, dass eine Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu demselben Netzsegment gehört wie die zugewiesene IP-Adresse; und

das Verfahren ferner Folgendes umfasst:

Empfangen (102) durch den Relaisagenten eines DHCP-Anforderungspakets von dem Client und Erfassen der IP-Adresse des Client aus einem Options-Feld 50 oder einem ciaddr-Feld des DHCP-Anforderungspakets; und

Hinzufügen (103) durch den Relaisagenten zu dem DHCP-Anforderungspaket der Gateway-IP-Adresse, die in den mehreren Gateway-IP-Adressen ist und zu demselben Netzsegment gehört wie die IP-Adresse des Client, und Senden des DHCP-Anforderungspakets mit der Gateway-IP-Adresse zu dem DHCP-Server, so dass der DHCP-Server die IP-Adresse dem Client zuweist.


 
2. Verfahren nach Anspruch 1, wobei das Verfahren vor dem Hinzufügen durch den Relaisagenten der mehreren Gateway-IP-Adressen zu einem DHCP-Findepaket des Client und Senden des DHCP-Findepakets zu dem DHCP-Server ferner Folgendes umfasst:

Erfassen durch den Relaisagenten des Typs des Client und der mehreren Gateway-IP-Adressen, die dem Typ des Client entsprechen, gemäß dem Typ des Client.


 
3. Relaisagent zum Erfassen einer Internetprotokoll-Adresse, IP-Adresse, der Folgendes umfasst:

einen anwenderseitigen Anschluss (501), der konfiguriert ist, mit einem Client zu verbinden, und konfiguriert ist, ein Findepaket des dynamischen Hostkonfigurationsprotokolls, DHCP-Findepaket, des Client zu empfangen;

einen Speicher (502), der konfiguriert ist, mehrere Gateway-IP-Adressen, die einem Typ des Client entsprechen, zu speichern;

einen netzseitigen Anschluss (503), der konfiguriert ist, mit einem DHCP-Server zu verbinden;

gekennzeichnet durch

einen ersten Prozessor (504), der ein Hinzufügungsmodul (701), das konfiguriert ist, die mehreren Gateway-IP-Adressen mehreren DHCP-Findepaketen, die durch den anwenderseitigen Anschluss empfangen werden, hinzuzufügen und jedem DHCP-Findepaket eine Gateway-IP-Adresse hinzuzufügen; und ein Sendemodul (702), das konfiguriert ist, die mehreren DHCP-Findepakete mit den Gateway-IP-Adressen zu dem DHCP-Server zu senden durch Verwenden des netzseitigen Anschlusses, so dass der DHCP-Server eine IP-Adresse dem Client zuweist und ein DHCP-Angebotspaket zu dem Client sendet nach dem Bestimmen, dass eine Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu demselben Netzsegment gehört wie die zugewiesene IP-Adresse, umfasst; oder

der erste Prozessor ein Replizierungsmodul (601), das konfiguriert ist, das DHCP-Findepaket zu replizieren, um mehrere DHCP-Findepakete zu erhalten; ein Hinzufügungsmodul (602), das konfiguriert ist, eine Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu jedem DHCP-Findepaket hinzuzufügen; und ein Sendemodul (603), das konfiguriert ist, die mehreren DHCP-Findepakete, die unterschiedliche Gateway-IP-Adressen führen, zu dem DHCP-Server zu senden durch Verwenden des netzseitigen Anschlusses, so dass der DHCP-Server eine IP-Adresse dem Client zuweist und ein DHCP-Angebotspaket zu dem Client sendet nach dem Bestimmen, dass eine Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu demselben Netzsegment gehört wie die zugewiesene IP-Adresse, umfasst; und

der Relaisagent ferner einen zweiten Prozessor (505) umfasst, der konfiguriert ist: die IP-Adresse des Client aus einem Options-Feld 50 oder einem ciaddr-Feld des DHCP-Anforderungspakets zu erfassen, nachdem ein DHCP-Anforderungspaket von dem Client durch den anwenderseitigen Anschluss empfangen worden ist, aus den mehreren Gateway-IP-Adressen eine Gateway-IP-Adresse auszuwählen, die zu demselben Netzsegment gehört wie die IP-Adresse des Client, die ausgewählte Gateway-IP-Adresse zu dem DHCP-Anforderungspaket hinzuzufügen und das DHCP-Anforderungspaket zu dem DHCP-Server zu senden, so dass der DHCP-Server die IP-Adresse dem Client zuweist.


 
4. Vorrichtung nach Anspruch 3, wobei der Relaisagent ein Zugangsmultiplexer einer digitalen Teilnehmerleitung, DSLAM, ein optisches Leitungsterminal, OLT, oder ein Mehrdienstzugangsknoten, MSAN, ist.
 
5. System zum Erfassen einer Internetprotokoll-Adresse, IP-Adresse, das einen Client, einen Relaisagenten und einen Server des dynamischen Hostkonfigurationsprotokolls, DHCP-Server, umfasst, wobei der Client über den Relaisagenten mit dem DHCP-Server verbunden ist; wobei der Relaisagent mit mehreren Gateway-IP-Adressen, die einem Typ des Client entsprechen, konfiguriert ist,
gekennzeichnet durch
den Relaisagenten, der konfiguriert ist, das DHCP-Findepaket von dem Client zu empfangen, das DHCP-Findepaket zu replizieren, um mehrere DHCP-Findepakete zu erhalten, eine Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu jedem DHCP-Findepaket hinzuzufügen und die mehreren DHCP-Findepakete, die unterschiedliche Gateway-IP-Adressen führen, zu dem DHCP-Server zu senden; oder den Relaisagenten, der konfiguriert ist, mehrere DHCP-Findepakete des Client zu empfangen, sequenziell die mehreren Gateway-IP-Adressen zu den mehreren DHCP-Findepaketen hinzuzufügen und die mehreren DHCP-Findepakete zu dem DHCP-Server zu senden, wobei jedes DHCP-Findepaket eine unterschiedliche Gateway-IP-Adresse führt;
den Relaisagenten, der ferner konfiguriert ist, ein DHCP-Anforderungspaket von dem Client zu empfangen, eine IP-Adresse des Client aus einem Options-Feld 50 oder einem ciaddr-Feld des DHCP-Anforderungspakets zu erfassen, aus den mehreren Gateway-IP-Adressen eine Gateway-IP-Adresse auszuwählen, die zu demselben Netzsegment gehört wie die IP-Adresse des Client, die ausgewählte Gateway-IP-Adresse zu dem DHCP-Anforderungspaket hinzuzufügen und das DHCP-Anforderungspaket zu dem DHCP-Server zu senden, so dass der DHCP-Server die IP-Adresse dem Client zuweist; und
den DHCP-Server, der konfiguriert ist, die IP-Adresse dem Client nach dem Empfangen des DHCP-Findepakets zuzuweisen und ein DHCP-Angebotspaket zu dem Client zu senden nach dem Bestimmen, dass eine Gateway-IP-Adresse in den mehreren Gateway-IP-Adressen zu demselben Netzsegment gehört wie die zugewiesene IP-Adresse.
 
6. System nach Anspruch 5, wobei der Relaisagent ferner konfiguriert ist:

den Typ des Client und die mehreren Gateway-IP-Adressen, die dem Typ des Client entsprechen, gemäß dem Typ des Client nach dem Empfangen des DHCP-Findepakets des Client zu erfassen.


 
7. System nach einem der Ansprüche 5 bis 6, wobei der Relaisagent ein Zugangsmultiplexer einer digitalen Teilnehmerleitung, DSLAM, ein optisches Leitungsterminal, OLT, oder ein Mehrdienstzugangsknoten, MSAN, ist.
 


Revendications

1. Procédé pour acquérir une adresse de protocole Internet, IP, dans un réseau, le réseau comportant un client, un agent de relais et un serveur sous protocole de configuration de serveur dynamique, DHCP, le client étant connecté au serveur DHCP via l'agent de relais, des adresses IP de passerelles multiples correspondant à un type du client étant configurées dans l'agent de relais, et le procédé étant caractérisé par les étapes consistant à :

faire recevoir (101), par l'agent de relais, le paquet de découverte DHCP en provenance du client, reproduire le paquet de découverte DHCP pour obtenir des paquets multiples de découverte DHCP, ajouter une adresse IP de passerelle parmi les adresses IP de passerelles multiples à chaque paquet de découverte DHCP, et envoyer les paquets multiples de découverte DHCP portant différentes adresses IP de passerelles au serveur DHCP, de telle façon que le serveur DHCP attribue une adresse IP au client, et envoie un paquet d'offre DHCP au client après avoir déterminé qu'une adresse IP de passerelle parmi les adresses IP de passerelles multiples appartient au même segment de réseau que l'adresse IP attribuée ; ou

faire recevoir (101), par l'agent de relais, des paquets multiples de découverte DHCP du client, ajouter séquentiellement les adresses IP de passerelles multiples aux paquets multiples de découverte DHCP, et envoyer les paquets multiples de découverte DHCP au serveur DHCP, chaque paquet de découverte DHCP transportant une adresse IP de passerelle différente, de telle façon que le serveur DHCP attribue une adresse IP au client, et envoie un paquet d'offre DHCP au client après avoir déterminé qu'une adresse IP de passerelle parmi les adresses IP de passerelles multiples appartient au même segment de réseau que l'adresse IP attribuée ; et

le procédé comportant en outre les étapes consistant à :

faire recevoir (102), par l'agent de relais, un paquet de demande DHCP en provenance du client, et acquérir l'adresse IP du client à partir d'un champ d'Option 50 ou d'un champ ciaddr du paquet de demande DHCP ; et

faire ajouter (103) par l'agent de relais, au paquet de demande DHCP, l'adresse IP de passerelle qui figure parmi les adresses IP de passerelles multiples et appartient au même segment de réseau que l'adresse IP du client, et envoyer le paquet de demande DHCP comportant l'adresse IP de passerelle au serveur DHCP, de telle façon que le serveur DHCP attribue l'adresse IP au client.


 
2. Procédé selon la revendication 1, le procédé comportant en outre, avant de faire ajouter, par l'agent de relais, les adresses IP de passerelles multiples à un paquet de découverte DHCP du client, et d'envoyer le paquet de découverte DHCP au serveur DHCP, l'étape consistant à :

faire acquérir, par l'agent de relais, le type du client et les adresses IP de passerelles multiples correspondant au type du client d'après le type du client.


 
3. Agent de relais servant à acquérir une adresse de protocole Internet, IP, comportant :

un port (501) côté utilisateur, configuré pour se connecter à un client, et configuré pour recevoir un paquet de découverte sous protocole de configuration de serveur dynamique, DHCP du client ;

une mémoire (502), configurée pour conserver des adresses IP de passerelles multiples correspondant à un type du client ;

un port (503) côté réseau, configuré pour se connecter à un serveur DHCP ;

caractérisé par

un premier processeur (504), qui comporte un module (701) d'ajout, configuré pour ajouter les adresses IP de passerelles multiples à des paquets multiples de découverte DHCP reçus par le port côté utilisateur, et ajouter une adresse IP de passerelle à chaque paquet de découverte DHCP ; et

un module (702) d'émission, configuré pour envoyer les paquets multiples de découverte DHCP comportant les adresses IP de passerelles au serveur DHCP en utilisant le port côté réseau, de telle façon que le serveur DHCP attribue une adresse IP au client, et envoie un paquet d'offre DHCP au client après avoir déterminé qu'une adresse IP de passerelle parmi les adresses IP de passerelles multiples appartient au même segment de réseau que l'adresse IP attribuée ; ou

le premier processeur comportant un module (601) de reproduction, configuré pour reproduire le paquet de découverte DHCP afin d'obtenir des paquets multiples de découverte DHCP ;

un module (602) d'ajout, configuré pour ajouter une adresse IP de passerelle parmi les adresses IP de passerelles multiples à chaque paquet de découverte DHCP ; et

un module (603) d'émission, configuré pour envoyer les paquets multiples de découverte DHCP portant différentes adresses IP de passerelles au serveur DHCP en utilisant le port côté réseau, de telle façon que le serveur DHCP attribue une adresse IP au client, et envoie un paquet d'offre DHCP au client après avoir déterminé qu'une adresse IP de passerelle parmi les adresses IP de passerelles multiples appartient au même segment de réseau que l'adresse IP attribuée ; et

l'agent de relais comportant en outre un deuxième processeur (505), configuré pour :

acquérir l'adresse IP du client à partir d'un champ d'Option 50 ou d'un champ ciaddr du paquet de demande DHCP après qu'un paquet de demande DHCP en provenance du client a été reçu par le port côté utilisateur, sélectionner, parmi les adresses IP de passerelles multiples, une adresse IP de passerelle qui appartient au même segment de réseau que l'adresse IP du client, ajouter l'adresse IP de passerelle sélectionnée au paquet de demande DHCP, et envoyer le paquet de demande DHCP au serveur DHCP, de telle façon que le serveur DHCP attribue l'adresse IP au client.


 
4. Dispositif selon la revendication 3, l'agent de relais étant un multiplexeur d'accès de ligne numérique d'abonné, DSLAM, un terminal de ligne optique, OLT, ou un noeud d'accès multiservice, MSAN.
 
5. Système destiné à acquérir une adresse de protocole Internet, IP, comportant un client, un agent de relais, et un serveur sous protocole de configuration de serveur dynamique, DHCP, le client étant connecté au serveur DHCP via l'agent de relais ;
l'agent de relais étant configuré avec des adresses IP de passerelles multiples correspondant à un type du client,
caractérisé en ce que
l'agent de relais est configuré pour recevoir le paquet de découverte DHCP en provenance du client, reproduire le paquet de découverte DHCP pour obtenir des paquets multiples de découverte DHCP, ajouter une adresse IP de passerelle parmi les adresses IP de passerelles multiples à chaque paquet de découverte DHCP, et envoyer les paquets multiples de découverte DHCP portant différentes adresses IP de passerelles au serveur DHCP ; ou
l'agent de relais est configuré pour recevoir des paquets multiples de découverte DHCP du client, ajouter séquentiellement les adresses IP de passerelles multiples aux paquets multiples de découverte DHCP, et envoyer les paquets multiples de découverte DHCP au serveur DHCP, chaque paquet de découverte DHCP transportant une adresse IP de passerelle différente ;
l'agent de relais est en outre configuré pour recevoir un paquet de demande DHCP en provenance du client, acquérir une adresse IP du client à partir d'un champ d'Option 50 ou d'un champ ciaddr du paquet de demande DHCP, sélectionner, parmi les adresses IP de passerelles multiples, une adresse IP de passerelle qui appartient au même segment de réseau que l'adresse IP du client, ajouter l'adresse IP de passerelle sélectionnée au paquet de demande DHCP, et envoyer le paquet de demande DHCP au serveur DHCP, de telle façon que le serveur DHCP attribue l'adresse IP au client ;
et
le serveur DHCP est configuré pour attribuer l'adresse IP au client après avoir reçu le paquet de découverte DHCP, et envoyer un paquet d'offre DHCP au client après avoir déterminé qu'une adresse IP de passerelle parmi les adresses IP de passerelles multiples appartient au même segment de réseau que l'adresse IP attribuée.
 
6. Système selon la revendication 5, l'agent de relais étant en outre configuré pour :

acquérir le type du client et les adresses IP de passerelles multiples correspondant au type du client d'après le type du client après avoir reçu le paquet de découverte DHCP du client.


 
7. Système selon l'une quelconque des revendications 5 à 6, l'agent de relais étant un multiplexeur d'accès de ligne numérique d'abonné, DSLAM, un terminal de ligne optique, OLT, ou un noeud d'accès multiservice, MSAN.
 




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