Cisco Systems OL-16066-01 appendix Table K-13 Advanced Interface Settings Dialog Box

Appendix K Router Platform User Interface Reference

		Advanced Interface Settings Page
Table K-13	Advanced Interface Settings Dialog Box (Continued)
ICMP Messages settings
Enable Redirect		When selected, enables the sending of Internet Control Message Protocol
Messages		(ICMP) redirect messages if the device is forced to resend a packet through
		the same interface on which it was received to another device on the same
		subnet. This is the default.
		When deselected, disabled redirect messages.
		Redirect messages are sent when the device wants to instruct the originator
		of the packet to remove it from the route and substitute a different device that
		offers a more direct path to the destination.
Enable Unreachable		When selected, enables the sending of ICMP unreachable messages. This is
Messages		the default.
		When deselected, disables unreachable messages.
		Unreachable messages are sent in two circumstances:
		• If the interface receives a nonbroadcast packet destined for itself that
		uses an unknown protocol. In this case, it sends an ICMP unreachable
		message to the source.
		• If the device receives a packet that it cannot deliver to its ultimate
		destination because it knows of no route to the destination address. In
		this case, it sends an ICMP host unreachable message to the originator
		of the packet.
		Note This is the only advanced setting supported by the null0 interface.
Enable Mask Reply		When selected, enables the sending of ICMP mask reply messages.
Messages		When deselected, disables mask reply messages. This is the default.
		Mask reply messages are sent in response to mask request messages, which
		are sent when a device needs to know the subnet mask for a particular
		subnetwork.

	User Guide for Cisco Security Manager 3.2
OL-16066-01		K-31