6-12 CHAPTER 6: ROUTING WITH IPX
A SAP packet consists of the following fields:
■Operation — This field indicates the type of operation the SAP packet performs. It can be set to one of the following values:
1=Request
2=Response
3=Get Nearest Server Request
4=Get Nearest Server Response
■Server Entry — Each
■Service Type — This
Although IPX routers use SAP, routers typically do not act as servers and require no Service Type assignment.
■Server Name — This field contains the
■Network Address — This
■Node Address — This
■Socket Address — This
■Hops to Server — This
By using SAP, servers can advertise their services and addresses. The information that these servers broadcast is not directly used by clients; rather it is collected by a SAP agent within each router on the server’s segment. The SAP agents store this information in a server information table. If the agents reside within a server, the information is also stored in their server’s bindery. The clients can then contact the nearest router or file server SAP agent for server information.