JP2003244188A - Tunnel communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tunnel communication method by which the number of performing PPP LCP authentication sequence between a subscriber terminal equipment which constructs an L2TP network and an LNS (L2TP network server) is reduced, in establishing a bulk communication by a multilink protocol of an L2TP (layer 2 tunneling protocol) session. <P>SOLUTION: In the L2TP network comprising the subscriber terminal equipment, an LAC (L2TP access concentrator) device, an L2TP tunnel switch device, and the LNS (L2TP network server) device, the L2TP tunnel switch device transmits parameters of a PPP LCP and a PPP authentication received from the LAC device by a proxy authentication/LCP (link control protocol) function to the LNS device by an AVP (attribute value pair) within a sequence signal of a session establishment protocol between the L2TP tunnel switch device and the LNS device, whereby the LNS device establishes the L2TP session between the subscriber terminal equipment and the LNS device. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to L2TP (Layer).
2 Tunneling Protocol (MP) of an L2TP session using an L2TP tunnel switching device having a function of consolidating L2TP tunnels by constructing a network.
A tunnel communication method that enables bulk communication by a protocol, especially PPP LCP (Point to Point Protocol L).
Ink Control Protocol parameters and PPP authentication (Point to Point Protocol Authentic)
ation) parameter transmission method.

An L2TP network to which the tunnel communication method as described above is applied is, as shown in FIG. 1, a subscriber terminal device 3
And LAC (L2TP Access Concentrator) device 4, 5
And an L2TP tunnel switch device 2 used for the purpose of aggregating a plurality of L2TP tunnels 7, and an LNS (L2TP Network Server) device 6 followed by the Internet.

[0003]

2. Description of the Related Art In bulk communication by MP of an L2TP session using a conventional L2TP tunnel switch device, as shown in FIG. 4, first, a PPP connection request signal (LCP) is sent between a subscriber terminal device and a LAC device. Conf Reques
t) and the acknowledgment signal for it (LPC Conf Ack)
Or PPP by confirmation request signal (LCP Conf Request), etc.
LCP Sequence 10 and CHAP Challenge (Chal
lenge Handshake authentication Protocol Challeng
e) signal and response signal to this signal (Chap Respons
Sequence 1 of PPP authentication such as e)
1 is negotiated between the subscriber terminal device and the LAC device, and then the L2TP tunnel establishment sequence 1 is performed between the LAC device and the L2TP tunnel switch device.
2 and the L2TP session establishment sequence 13 establishes the L2TP tunnel and the L2TP session. Next, the L2TP tunnel establishment sequence 12 and the L2TP session establishment sequence 13 establish the L
A 2TP tunnel and an L2TP session are established, and finally, between the subscriber terminal device and the LNS device, the PPP
The first L2 between the subscriber terminal device and the LNS device is negotiated by the LCP sequence 10 and the PPP authentication sequence 11.
The TP session is established, and the second L2TP session is performed in the same manner as the first sequence.

As described above, in bulk communication by MP of the L2TP session using the conventional L2TP tunnel switch device, the parameters of PPP LCP and P
The parameters for PP authentication are L2TP
Since it cannot be directly transmitted from the tunnel switch device to the LNS device, the transmission is performed by a PPP LCP / authentication sequence between the subscriber terminal device and the LNS device. Therefore, the subscriber terminal device is L
Parameter negotiation with both the LAC device and the LNS device is required before establishing the L2TP session with the NS device. Therefore, in order to realize bulk communication by the MP, it is necessary to execute the PPP LCP / authentication sequence four times in total. There is.

[0005]

As described above, in the prior art, the PPP LCP / authentication sequence must be executed four times in total when establishing bulk communication by the MP of the L2TP session. Even a normal PPP MP connection is only twice PPP LCP
/ Authentication sequence is not executed, depending on the implementation of PPP, 3 or more PPP LC
There is a problem that the P / authentication sequence may not be supported in some cases.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art by using an L2TP tunnel switch device with a proxy authentication (Proxy Authenticati).
on) / PP received from LAC device by LCP function
By transmitting the parameter of P LCP and the parameter of PPP authentication to the LNS device by the tunnel communication method of the present invention, the number of executions of the PPP LCP / authentication sequence is reduced, and the PP
It is intended to enable bulk communication by MP of an L2TP session using an L2TP tunnel switch device that does not depend on the implementation of P.

[0007]

To achieve the above object, the present invention provides a subscriber terminal device, a LAC device, and an L2T.
In an L2TP network composed of a P tunnel switch device and an LNS device, the L2TP tunnel switch device is a proxy authentication / LC.
PPP L negotiated between the subscriber terminal device and the LAC device transmitted from the LAC device by the P function
It receives the parameters of the CP and the parameters of the PPP authentication, and uses these received parameters as the L2 between the L2TP tunnel switch device and the LNS device.
Protocol sequence signal I for establishing a TP session
L by AVP (Attribute value Pair) in CCN
The LNS device transmits it to the NS device, and the LNS device receives the PPP LCP parameter and P negotiated between the subscriber terminal and the LAC device received from the L2TP tunnel switch.
A tunnel communication method is characterized by establishing an L2TP session between a subscriber terminal device and an LNS device according to a PP authentication parameter.

According to the tunnel communication method of the present invention implemented in the L2TP tunnel switch, the LNS device can establish the L2TP session without executing the PPP LCP / authentication sequence with the subscriber terminal device. Further, the PPP LCP parameters and the PPP authentication parameters transmitted by the tunnel communication method according to the present invention are similar to those of the conventional proxy authentication / LCP.
L2T between L2TP tunnel switch device and LNS device
Since it is transmitted by an AVP (Attribute value Pair) in the ICCN, which is a protocol sequence signal when establishing a P session, no special implementation is required for the LNS device.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail based on the embodiments of the present invention.

In this embodiment, as shown in FIG. 1, L2TP is used.
L2TP network 1 is constructed as a VPN (Virtual Private Network) network using L2TP tunnel switch device 2 and is used for the purpose of consolidating a plurality of L2TP tunnels 7, and between subscriber terminal device 3 and LNS device 6. At PPP
The session is terminated so that the LAC device 4 and the LNS device 6 terminate the L2TP tunnel.

FIG. 2 is a diagram for explaining the tunnel communication method according to the present invention, in which the same parts as those in FIG. 1 are designated by the same reference numerals, and 14 is a subscriber unit. PPP LCP / authentication sequence between 3 and LAC device 4, 15 proxy authentication / LCP function, 16 LAC device 4 and L2
Establishing L2TP sessions 8 and 9 (see FIG. 1) between the TP tunnel switch devices 2 and 17 indicating transmission of PPP LCP parameters and PPP authentication parameters, respectively.

As shown in FIG. 2, in the tunnel communication system of the present invention implemented in the L2TP tunnel switch device 2, the proxy authentication / LCP function 1 is used.
5, which is the parameter of the PPP LCP received from the LAC device 4 by (5) (1) the first received LCP connection request signal (Initial Received LCP CONFREQ), and (2) the last transmitted LCP connection request signal (Last Sent LCP CONF).
REQ) and (3) Last connection request signal (L
ast Received LCP CONFREQ) and PPP authentication parameters (4) Proxy Authen Type,
(5) Proxy authentication name signal (Proxy Authen Name), (6) Proxy authentication challenge signal (Proxy Authen Challeng)
e), (7) Proxy authentication ID signal
(Proxy Authen ID) and (8) Proxy authentication response signal (Proxy Authen Response)
L2 between the 2TP tunnel switch device 2 and the LNS device 6
It is transmitted to the LNS device 6 by the AVP in the ICCN, which is a protocol sequence signal when establishing a TP session.

According to the present invention, the subscriber terminal device 3 and the LA
The parameters of the PPP LCP and the PPP authentication performed in the sequence of PPP LCP / authentication between the C devices 4 are L
For transmission from the AC device 4 to the L2TP tunnel switch device 2 and further from the L2TP tunnel switch device 2 to the LNS device 6, the PPP LC between the subscriber terminal device 3 and the L2TP tunnel switch device 2 and the LNS device 6 is transmitted.
The P / authentication sequence is no longer needed. Therefore, the PPP LCP / authentication sequence required until one L2TP session is established is once, and the sequence is only required twice in bulk communication by the MP of the L2TP session.

Next, from the start of the connection request from the subscriber terminal device 3, the first L2TP session is established, the second L2TP session is established, and the bulk communication by the multilink protocol (MP) is performed. The steps will be described with reference to FIG.

As shown in FIG. 3, the subscriber terminal device 3 transmits a PPP connection request signal (LCP ConfRequest), and accordingly, the PPP LCP / authentication is performed between the subscriber terminal device 3 and the LAC device 4. Sequences 10 and 11 are executed to negotiate the PPP LCP parameters and the PPP authentication parameters.

When the parameter negotiation between the subscriber terminal device 3 and the LAC device 4 is completed, the LAC device 4 establishes an L2TP tunnel and an L2TP session with the L2TP tunnel switch device 2, in sequence 12, 13. To execute. At this time, the proxy authentication / LCP function of the LAC device 4 negotiates the PPP LCP parameter and the PPP authentication parameter between the subscriber terminal device 3 and the LAC device 4 by the AVP in the ICCN of the sequence signal. Is transmitted to the L2TP tunnel switch device 2.

After the L2TP session is established between the LAC device 4 and the L2TP tunnel switching device 2 as described above, the L2TP tunnel switching device 2 operates in the LNS.
Establishment of L2TP tunnel with device 6 and L2TP
The session establishment sequences 12 and 13 are executed, and at this time, the sequence signal L
The PPP LCP parameter and the PPP authentication parameter negotiated between the subscriber terminal device 3 and the LAC device 4 received from the AC device 4 are transmitted to the LNS device 6.

As described above, the first L2TP session is established between the subscriber terminal device 3 and the LNS device 6.
The PPP LCP / authentication sequence performed so far is one time. Second L2TP
The session is performed in the same manner, and after the establishment, the link of the L2TP session is bundled by the first and MP.

[0019]

As described above in detail, according to the present invention, the PPP LCP parameter and the PPP authentication parameter transmitted from the LAC device to the L2TP tunnel switch device are directly transmitted to the LNS device. PPP until L2TP session is established
The LCP / authentication sequence only needs to be executed once, and therefore the L2TP session M
PPP LCP / required for bulk communication by P
The authentication sequence is 2 times, and P
Bulk communication by MP of an L2TP session using an L2TP tunnel switch device is possible regardless of implementation of PP.

[Brief description of drawings]

FIG. 1 is a diagram illustrating an L2TP tunnel switching device having a function of constructing an L2TP network and consolidating L2TP tunnels.

FIG. 2 is a diagram illustrating a tunnel communication system.

FIG. 3 is a diagram illustrating bulk communication by a multilink protocol of an L2TP session using an L2TP tunnel switch device that implements a tunnel communication method.

FIG. 4 is a diagram illustrating bulk communication of an L2TP session using a conventional L2TP tunnel switching device according to a multilink protocol.

[Explanation of symbols]

1 L2TP network 2 L2TP tunnel switch device 3 subscriber terminal device 4, 5 LAC device 6 LNS device 7 L2TP tunnel 8, 9 L2TP session 10 PPP LCP sequence 11 PPP authentication sequence 12 L2TP tunnel establishment sequence 13 L2TP session establishment Sequence 14 PPP LCP / Authentication Sequence 15 Proxy Authentication / LCP Function 16 L2TP Session Establishment 17 PPP LCP Parameters and PPP Authentication Parameter Transmission

Claims (3)

[Claims] 1. A subscriber terminal device and LAC (L2TP Acce
ss Concentrator) device and L2TP (Layer 2 Tunneli)
ng Protocol) tunnel switch device and LNS (L2TP N
In an L2TP network configured with an etwork server) device, the L2TP tunnel switch device is a proxy authentication / LCP (Proxy Authenti
LAC by cation / Link Control Protocol) function
PPP LCP (Point to Point) negotiated between the subscriber terminal device and the LAC device transmitted from the device.
Protocol Link Control Protocol) parameter and P
AVP (Attr) in the protocol sequence signal ICCN that receives the parameters of the PP authentication and establishes the L2TP session between the L2TP tunnel switch device and the LNS device by receiving these received parameters.
ibute value Pair) to the LNS device,
The NS device negotiates the PP received by the L2TP tunnel switch with the subscriber terminal and the LAC device.
A tunnel communication method characterized by establishing an L2TP session between a subscriber terminal device and an LNS device by a parameter of PLCP and a parameter of PPP authentication. 2. The PP for which the LAC device first receives the parameter of the PPP LCP from the subscriber terminal device.
The connection request signal of P, the signal last transmitted by the subscriber terminal device to the LAC device, and the connection request signal of PPP last received by the LAC device from the subscriber terminal device. The tunnel communication method described. 3. The PPP authentication parameters include a proxy authentication type signal, a proxy authentication name signal, a proxy authentication challenge signal, a proxy authentication ID signal, and a proxy authentication ID signal. The tunnel communication method according to claim 1, wherein the response signal is a proxy authentication response signal.