protocol) broadcasts. These advertisements are sent every 60 seconds by
default, and are heard by all servers and routers. In order for clients to find
their desired resource initially, the nearest server needs to have an entry in its
SAP table for that resource. The advantage to the SAP system is that all serv-
ers (barring access lists) are aware of all resources in the internetwork, and
the client can obtain the information from any server. The disadvantage is
that the SAP process doesn't scale well--the server's processor and the net-
work itself must transmit and process all the information about all the
resources. This can reduce overall network availability for user functions.
These issues will be reviewed later in this chapter.
sent out each interface on the router or server to populate all other resources.
This is an important consideration in troubleshooting because a problem in