Connecting to a Novell Network
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forwarding or storing the SAP table on any server or router can cause ser-
vices to be unavailable.
Because SAP information is shared among all servers, the servers eventu-
ally become aware of all available services and are thereby equipped to
respond to client GNS requests. As new services are introduced, they're auto-
matically added to local SAP tables and added to new broadcasts to populate
other servers.
Unless the configuration is modified, SAPs are sent from each IPX router
interface at 60-second intervals--identical to NetWare servers. This is a sig-
nificant point, especially with WAN links, where bandwidth may be limited.
The router isolates SAP broadcasts to individual segments and passes along
only the summarized information to each segment.
A SAP broadcast decodes with an EtherPeek analyzer, as follows:
Flags: 0x00
Status: 0x00
Packet Length:306
Timestamp: 23:48:36.362000 06/28/1998
Ethernet Header
Destination: ff:ff:ff:ff:ff:ff Ethernet Brdcast
Source: 00:80:5f:ad:14:e4
Protocol Type:81-37 NetWare
IPX - NetWare Protocol
Checksum: 0xffff
Length: 288
Transport Control:
Reserved: %0000
Hop Count: %0000
Packet Type: 4 PEP
Destination Network: 0xcc715b00
Destination Node: ff:ff:ff:ff:ff:ff Ethernet Brdcast
Destination Socket: 0x0452 Service Advertising Protocol
Source Network: 0xcc715b00
Source Node: 00:80:5f:ad:14:e4
Source Socket: 0x0452 Service Advertising Protocol
SAP - Service Advertising Protocol
Operation: 2 NetWare General Service Response
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