C H A P T E R44
• Describe the Network Link-Service Protocol.
• Describe routing with NLSP.
• Describe the data packet used by NLSP.
NetWare Link-Services Protocol
The NetWare Link-Services Protocol (NLSP) is a link-state routing protocol from Novell designed to
overcome some of the limitations associated with the IPX Routing Information Protocol (RIP) and its
companion protocol, the Service Advertisement Protocol (SAP). NLSP is based on the OSI Intermediate
System-to-Intermediate System (IS-IS) protocol and was designed to replace RIP and SAP, Novell’s
original routing protocols that were designed when internetworks were local and relatively small. As
such, RIP and SAP are not well suited for today’s large, global internetworks. This chapter summarizes
the routing processes and protocol components of NLSP.
Compared to RIP and SAP, NLSP provides improved routing, better efficiency, and scalability. In
addition, NLSP-based routers are backward compatible with RIP-based routers. NLSP-based routers use
a reliable delivery protocol, so delivery is guaranteed. Furthermore, NLSP facilitates improved routing
decisions because NLSP-based routers store a complete map of the network, not just next-hop
information such as RIP-based routers use. Routing information is transmitted only when the topology
has changed, not every 60 seconds as RIP-based routers do, regardless of whether the topology has
changed. Additionally, NLSP-based routers send service-information updates only when services
change, not every 60 seconds as SAP does.
NLSP is efficient in several ways. It is particularly useful over a WAN link because its support of IPX
header compression makes it possible to reduce the size of packets. NLSP also supports multicast
addressing so that routing information is sent only to other NLSP routers, not to all devices, as RIP does.
In addition, NLSP supports load balancing across parallel paths and improves link integrity. It
periodically checks links for connec