- Enterasys Security Router User's Guide

General IP Features
5-2 Configuring IP
• The Router ID can be configured with the ip router-id command or, if not configured,
automatically generated from the existing configuration. Alternately, the Router ID is
automatically generated as the highest non-zero IP address among all loopback interfaces or,
if no loopback interface is configured, the highest non-zero IP address among standard
configured interfaces. A loopback interface can be configured with the
interface loopback
command.
•BOOTP/DHCP relay
• Broadcasting: Directed and UDP broadcast forwarding
•ICMP
– ICMP Router Discovery Protocol
– Destination unreachable message
– Time exceeded message
– Parameter problem message
– Redirect message
– Echo or echo reply message
•TCP
– Window and acknowledgement
– TCP maximum segment size
– Congestion control in TCP/IP
– TCP extensions for high performance
– TCP selective acknowledgement option
•UDP
•Telnet
•SSH
•TFTP
•MTU
– Path MTU discovery protocol: Support for external MTU discovery (data passing through
the XSR). An ICMP MTU size exceeded message is issued if large packets transit the XSR
with the “don't fragment” bit set. These packets are dropped per RFC-1191. Also, the XSR
does not originate MTU discovery, that is, application data originating in the XSR.
– Set MTU size per interface
• IP Interface
–Numbered interfaces
– Un-numbered interfaces on point to point links
– NBMA support
‐ Pointtomultipointnetworks
‐ Fullymeshednetworks
–Secondary IP