FINS/TCP Method

Section 7-4

Connection Sequence for Automatic Allocation of FINS Node Addresses

ClientServer

 

 

 

accept

 

connect

 

SYN

 

 

 

 

SYN, ACK

 

 

 

 

ACK

 

 

send

A

 

 

 

 

B

 

 

 

 

recv

 

 

 

ACK

 

 

 

Normal

 

 

C

 

D

send

 

 

 

 

recv

 

 

 

 

ACK

 

 

 

 

 

 

 

F

E

send

 

 

 

 

recv

 

 

 

 

ACK

 

 

 

 

 

Socket interface

 

E

 

connect

send

 

 

 

 

F

 

Message from TCP/IP layer

 

 

recv

 

 

 

 

 

ACK

 

 

 

 

Message from host layer

 

 

 

 

1,2,3... 1. The client specifies the client node address as 00000000 hexadecimal in the server as the automatically allocated FINS node address, and sends it using the FINS NODE ADDRESS DATA SEND (CLIENT TO SERVER) command.

2.The server checks the client node address in the received command to see whether an automatically allocated FINS node address is specified, and the client node address is determined from the automatically allocated FINS node addresses controlled by the server.

3.The server stores its own node address in the server node address field and the automatically allocated client FINS node address in the client node address field, and sends to the client using the FINS NODE ADDRESS DATA SEND (SERVER TO CLIENT) command.

4.The server node address is obtained from the server node address field in the received command, and the client node address is obtained from the client node address field.

5.A FINS message is sent using the FINS FRAME SEND command.

6.The FINS message is separated out from the received command.

Note In steps 5 and 6, both the client and server can send and receive FINS mes- sages (commands/responses) in both directions.

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