Does ICMP support redirection?

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An ICMP redirect message is an out-of-band message that is designed to inform a host of a more optimal route through a network, but possibly used maliciously for attacks that redirect traffic to a specific system.

How do I redirect an ICMP?

ICMP Redirect messages are sent by a first-hop router to inform a computer inside its network segment, that there is another router in the same network segment that can deliver the packet more efficiently to that particular destination network/host.

Under what conditions will an ICMP redirect message be sent?

Cisco IOS routers will send ICMP redirects when the following conditions are met: The IP packet should be received and transmitted on the same interface. The source IP address of the incoming packet should be on the same subnet as the new next hop IP address. The IP packet doesn’t use source routing.

How do I disable ICMP redirects?

Configure the host system to ignore IPv4 ICMP redirect messages.

Open the /etc/sysctl. conf file.
If the values are not set to 0 , add the following entries to the file or update the existing entries accordingly. Set the value to 0 .
Save the changes and close the file.
Run # sysctl -p to apply the configuration.

What are the different types of ICMP messages?

Internet Control Message Protocol (ICMP) Parameters

Type 0 — Echo Reply.
Type 1 — Unassigned.
Type 2 — Unassigned.
Type 3 — Destination Unreachable.
Type 4 — Source Quench (Deprecated)
Type 5 — Redirect.
Type 6 — Alternate Host Address (Deprecated)
Type 7 — Unassigned.

What are ICMP protocols?

The Internet Control Message Protocol (ICMP) is a protocol that devices within a network use to communicate problems with data transmission. In this ICMP definition, one of the primary ways in which ICMP is used is to determine if data is getting to its destination and at the right time.

What is ICMP redirect in Linux?

An ICMP redirect packet is generated by a router to inform a host of a better route to some specific destination. The recipient of an ICMP redirect overrides its route table with the information given in the redirect packet.

What are 5 types of errors handled by ICMP messages?

ICMP uses the source IP address to send the error message to the source (originator) of the datagram. Five types of errors are handled: destination unreachable, source quench, time exceeded, parameter problems, and redirection (see figure1).

What are ICMP messages used for?

Internet Control Message Protocol (ICMP) is used for reporting errors and performing network diagnostics. In the error reporting process, ICMP sends messages from the receiver to the sender when data does not come though as it should.

What is ICMP error message?

ICMP (Internet Control Message Protocol) is an error-reporting protocol that network devices such as routers use to generate error messages to the source IP address when network problems prevent delivery of IP packets.