ICMP (Internet Control Message Protocol)

In order to improve the delivery of IP datagrams chances of success, at the network layer of the Internet Control Message Protocol (Internet Control Message Protocol, ICMP) to allow the host or router report errors and anomalies. ICMP data packet as the IP layer datagram, the datagram header plus composition IP datagram sent.

ICMP is an IP layer protocol

CIMP packet type

There are two types, namely ICMP error reporting packets and ICMP packets inquiry.

ICMP error message type:

1. Not end up
2. Source inhibition
3. More than
4. Parameter Problem
5. Change the routing (redirect)

ICMP message types to ask:

1. Echo request and reply messages
2. Timestamp request and reply messages
3. Address mask request and reply messages
4. Router advertisement message and ask

ICMP Application:

• The PING (packet network probe):

Purpose: to test the communication between two hosts;

ICMP applications: using ICMP echo request and reply messages;

Work in the application layer;

• traceroute (name of Unix, the win is tracert):

Usage: used to track the route the packet;

ICMP applications: using the ICMP time exceeded message;

Works at the network layer;