Product guide

IP Routing Features
Overview of IP Routing
Parameter Description Default See page
Time to Live
(TTL)
The maximum number of routers (hops) through which a
packet can pass before being discarded. Each router
decreases a packet’s TTL by 1 before forwarding the
packet. If decreasing the TTL causes the TTL to be 0, the
router drops the packet instead of forwarding it.
64 hops Refer to the
chapter titled
“Configuring IP
Addressing” in
the Management
and Configuration
Guide.
Directed
broadcast
forwarding
A directed broadcast is a packet containing all ones (or
in some cases, all zeros) in the host portion of the
destination IP address. When a router forwards such a
broadcast, it sends a copy of the packet out each of its
enabled IP interfaces.
Note: You also can enable or disable this parameter on
an individual interface basis. See table 11-2 on page 11-
12.
Disabled 11-17
ICMP Router
Discovery
Protocol
(IRDP)
An IP protocol that a router can use to advertise the IP
addresses of its router interfaces to directly attached
hosts. You can enable or disable the protocol at the Global
CLI Config level.
You also can enable or disable IRDP and configure the
following protocol parameters on an individual VLAN
interface basis at the VLAN Interface CLI Config level.
• Forwarding method (broadcast or multicast)
• Hold time
• Maximum advertisement interval
• Minimum advertisement interval
• Router preference level
Disabled 11-76
11-77
Static route An IP route you place in the IP route table. No entries 11-20
Default
network
route
The router uses the default network route if the IP route
table does not contain a route to the destination. Enter an
explicit default route (0.0.0.0 0.0.0.0 or 0.0.0.0/0) as a static
route in the IP route table.
None configured 11-23
11-8