Network system

• US 20030182434A1
• Filed: 08/16/2002
• Published: 09/25/2003
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Matsumoto, Norihisa, Ogushi, Minoru
• Granted Patent: US 7,512,688 B2
• Time in Patent Office: Days
• US Class Current: 709/228
• CPC Class Codes: H04L 12/4608 LAN interconnection over ATM networks
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 2212/00 Encapsulation of packets

Abstract

Disclosed is a network system that can distribute connection requests from PPPoE client terminals to specific PPPoE servers under the initiative of the PPPoE servers. In the system that realizes connection between at least one client terminal and plural servers at least by a connection start signal from the client terminal, a connection provision signal from the servers, corresponding to the connection start signal, and a connection request signal from the client terminal, corresponding to the connection provision signal; the servers have an identification information setting means, upon receiving a connection start signal from the client terminal, for setting server identification information for identifying a specific server to receive a connection request signal corresponding to the connection start signal in the connection provision signal.

Claims

1. A network system that realizes connection between at least one client terminal and plural server apparatuses at least by a connection start signal from the client terminal, a connection provision signal from the servers, corresponding to the connection start signal, and a connection request signal from the client terminal, corresponding to the connection provision signal,

wherein the server apparatuses have an identification information setting means, upon receiving a connection start signal from the client terminal, for setting server identification information for identifying a specific server apparatus to receive a connection request signal corresponding the connection start signal in the connection provision signal.

2. The network system according to claim 1, wherein:

the client terminal includes signal returning means for setting the server identification information contained in the received connection provision signal in the connection request signal and returning the connection request signal; and

the server apparatuses include;

identification information extracting means for extracting the server identification information contained in the received connection request signal; and

signal receiving means for receiving the connection request signal, based on the result of comparing the server identification information and their own server identification information.

3. The network system according to claim 1 or 2,

wherein the server apparatuses include:

load information setting means, upon receiving a connection start signal from the client terminal, for setting the their own server identification information and their own load information in the connection provision signal;

load information extracting means, upon observing a connection provision signal sent from other server apparatuses, for extracting the server identification information and the load information set in the connection provision signal; and

server identifying means for deciding a server apparatus to receive the connection request signal, based on the extracted load information of each server apparatus.

4. The network system according to claim 1, wherein:

the network system is a PPPoE network system comprising at least one PPPoE client terminal and plural PPPoE server apparatuses;

the connection start signal is a PADI message, the connection provision signal is a PADO message, and the connection request signal is a PADR message;

MAC addresses of the PPPoE server apparatuses, used for communications with the PPPoE client terminals are set to be different from each other; and

the identification information setting means sets, as the server identification information, a MAC address of the specific PPPoE server apparatus in the PADO message.

5. The network system according to claim 4,

wherein the PPPoE server apparatuses include:

load information setting means, upon receiving a PADI message from the PPPoE client terminal, for setting the their own MAC address and their own load information in a PADO message;

load information extracting means, upon observing a PADO message sent from other server apparatuses, for extracting the MAC address and the load information set in the PADO message; and

server identifying means for deciding a PPPoE server apparatus to receive the PADR message, based on the extracted load information of each server apparatus.

6. The network system according to claim 5, wherein:

the PPPoE server apparatuses include storing means for storing the extracted MAC address and the load information; and

the PPPoE server apparatuses respond to a PADI message from the PPPoE client terminal with a PADO message and mutually update load information stored in the storing means.

7. The network system according to claim 1, wherein:

the network system is a PPPoE network system comprising at least one PPPoE client terminal and plural PPPoE server apparatuses;

the connection start signal is a PADI message, the connection provision signal is a PADO message, and the connection request signal is a PADR message;

MAC addresses of the PPPoE server apparatuses used for communications with the PPPoE client terminals are set to be identical with each other; and

the identification information setting means sets, as the server identification information, a server identifier not overlapping among PPPoE server apparatuses that is different from the MAC addresses, in the PADO message.

8. The network system according to claim 7, wherein:

the PPPoE client terminal has message returning means for setting the server identifier contained in the received PADO message in the PADR message and returning the PADR message;

the PPPoE server apparatuses include;

identifier extracting means for extracting the server identifier contained in the received PADR message; and

message receiving means, based on the result of comparing the server identifier and their own server identifier, for comparing the server identifier and their own server identifier and receiving the PADR message if both match.

9. The network system according to one of claims 4 to 8, wherein the PPPoE server apparatuses include:

session ID list setting means for setting a list of the session IDs of PPPoE sessions established by the own server apparatuses in a PADO message;

message observing means for observing PADO messages sent by other PPPoE server apparatuses;

session ID list extracting means for extracting a list of the session IDs set in the observed PADO message; and

session ID assigning means for assigning a session ID value not overlapping the extracted session ID values when a PADR request signal is received to establish a new PPPoE session.

10. The network system according to one of claims 4 to 9,

wherein the PPPoE server apparatuses include:

load information setting means, upon receiving a PADI message from the PPPoE client terminal, for setting the their own server identifier and their own load information in a PADO message;

load information extracting means, upon observing a PADO message sent from other server apparatuses, for extracting the server identifier and the load information set in the PADO message; and

server identifying means for deciding a PPPoE server apparatus to receive the PADR message, based on the extracted load information of each server apparatus.

11. The network system according to claim 10, wherein:

the PPPoE server apparatuses include storing means for storing the extracted server identifier and the load information; and

the PPPoE server apparatuses respond to a PADI message from the PPPoE client terminal with a PADO message and mutually update load information stored in the storing means.

12. The network system according to claim 10 or 11,

wherein the PPPoE server apparatuses include at least one of:

PADO message sending means, upon receiving a PADI message from an apparatus other than the PPPoE client terminal, for sending a PADO message for updating load information stored in the PPPoE server apparatuses; and

PADI message sending means for sending a PADI message to update load information of other PPPoE server apparatuses stored in the own server apparatuses.

13. The network system according to one of claims 4 to 12, wherein:

the PPPoE server apparatuses include;

time information setting means, upon receiving a PADI message from the PPPoE client terminal, for setting receive time information indicating receive time of the PADI message in a PADO message; and

time information extracting means, upon receiving the PADR message, for extracting the receive time information contained in the PADR message;

the PPPoE client terminal includes message returning means for setting the receive time information contained in the received PADO message in the PADR message and returning the PADR message; and

the PPPoE server apparatuses include judging means for judging whether the PADR message is valid or invalid, based on the result of comparing receive time of the PADR message and time indicated by the receive time information.

14. The network system according to one of claims 4 to 13, wherein the PPPoE server apparatuses:

include encrypting means and decrypting means;

set information encrypted by the encrypting means in a PADO message; and

extract the encrypted information from a PADO message or a PADR message returned in response to the PADO message, and decrypt encrypted information extracted by the decrypting means.

15. A server apparatus that realizes connection with at least one client terminal at least by a connection start signal from the client terminal, a connection provision signal from the server apparatus, corresponding to the connection start signal, and a connection request signal from the client terminal, corresponding to the connection provision signal,

wherein the server apparatus has an identification information setting means, upon receiving a connection start signal from the client terminal, for setting server identification information for identifying a specific server apparatus to receive a connection request signal corresponding the connection start signal in the connection provision signal.

16. The server apparatus according to claim 15, including:

connection request signal receiving means for receiving a returned connection request signal in which the server identification information contained in a connection provision signal received by the client terminal is set;

identification information extracting means for extracting the server identification information contained in the received connection request signal; and

signal receiving means, based on the result of comparing the server identification information and its own server identification information, for comparing the server identification information and its own server identification information and receiving the connection request signal if both match.

17. The server apparatus according to claim 15 or 16, including:

session ID list setting means for setting a list of the session IDs of sessions established by the own server apparatuses in a connection provision signal;

signal observing means for observing connection provision signals sent by other server apparatuses;

session ID list extracting means for extracting a list of the session IDs set in the observed connection provision signal; and

session ID assigning means for assigning a session ID value not overlapping the extracted session ID values when a connection request is received to establish a new session.

18. The server apparatus according to one of claims 15 to 17,

including:

load information setting means, upon receiving a connection start signal from the client terminal, for setting the its own server identification information and its own load information in a connection provision signal;

load information extracting means, upon observing a connection provision signal sent from other server apparatuses, for extracting the server identification information and the load information set in the connection provision signal; and

server identifying means for deciding a server apparatus to receive the connection request signal, based on the extracted load information of each server apparatus.

19. The server apparatus according to one of claims 15 to 18, wherein:

the server apparatus is a PPPoE server apparatus used in a PPPoE network system comprising at least one PPPoE client terminal and plural PPPoE server apparatuses;

the connection start signal is a PADI message, the connection provision signal is a PADO message, and the connection request signal is a PADR message;

MAC addresses of the PPPoE server apparatuses, used for communications with the PPPoE client terminals are set to be different from each other; and

the identification information setting means sets, as the server identification information, a MAC address of the specific PPPoE server apparatus in the PADO message.

20. The server apparatus according to one of claims 15 to 18, wherein:

the server apparatus is a PPPoE server apparatus used in a PPPoE network system comprising at least one PPPoE client terminal and plural PPPoE server apparatuses;

the connection start signal is a PADI message, the connection provision signal is a PADO message, and the connection request signal is a PADR message;

MAC addresses of the PPPoE server apparatuses, used for communications with the PPPoE client terminals are set to be identical with each other; and

the identification information setting means sets, as the server identification information, a server identifier not overlapping among PPPoE server apparatuses that is different from the MAC addresses, in the PADO message.