TMS zl Management and Configuration Guide ST.1.0.090213

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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 VLANs in the backbone area as well
as one or more VLANs in other areas. The module acts as the router for
inter-area traffic.
■ Internal router
The module has VLANs 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 VLANs. In other words, the module only sends LSAs for VLANs 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 OSPF. 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 VLANs 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 VLAN interfaces
■ Configurable OSPF timers