TMS zl Management and Configuration Guide ST.1.1.100226

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Overview
Routing
Depending on your needs, the TMS zl Module can be configured to act in any
of these roles:
■ Area Border Router (ABR)
The TMS zl Module has one or more interfaces in the backbone area as
well as one or more interfaces in other areas. The module acts as the
router for inter-area traffic.
■ Internal router
The module has interfaces in one area only.
■ Autonomous System Border Router (ASBR)
The module is either an internal router or an ABR. It also connects to a
router in another autonomous system. Routers that redistribute routes
into OSPF are also ASBRs.
By default, the TMS zl Module does not redistribute routes to its own con-
nected interfaces. In other words, the module only sends LSAs for interfaces
that are placed in an OSPF area. However, you can configure the module to
redistribute connected routes as well as static routes and routes discovered
through RIP. You can configure the metric for redistributed routes, but all
types of redistributed routes have the same metric.
Note Redistributed routes are advertised as type 5 LSAs. The TMS zl Module can
only send these LSAs on interfaces in the backbone area, normal areas, and
NSSAs.
By default, the TMS zl Module firewall allows all OSPF messages between any
zone and the Self zone. For greater security, the TMS zl Module supports these
types of OSPF authentication:
■ Simple password
■ MD5
Other OSPF options supported by the TMS zl Module include:
■ RFC-1583 compatibility
The TMS zl Module supports the most current RFC concerning OSPF
(RFC 2328), which eliminates routing loops from multiple external routes
to the same networks. However, if other routers in your system support
only RFC 1583, you can configure the module for backward compatibility.
■ Configurable administrative distance for OSPF routes
■ Configurable router ID
■ Configurable router priority
■ Configurable cost for interfaces
■ Configurable OSPF timers