ICMP
[TCP/IP Base Protocols]

Files
file	icmp.h
	ICMP Module for Modtronix TCP/IP Stack.

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Detailed Description

The ICMP layer is implemented by the file 'ICMP.c'. The header file "icmp.h" defines the services provided by the layer. In this architecture, the ICMP layer is a passive layer; it does not respond to the ICMP data packet. Instead, higher level layers use ICMP primitives and fetch the ICMP packet, interpret it and take appropriate action.

Normally, ICMP is used to send and receive IP error or diagnostic messages. In the Modtronix TCP/IP Stack, ICMP implements ICMP primitives that can be used to generate any of the ICMP messages. In embedded applications, ICMP is useful for diagnostic purpose. When enabled, ICMP can respond to 'ping' packets, thus allowing a remote host to determine local host presence.

The Microchip ICMP layer only responds to ping data packets of up to 32 bytes; larger packets will be ignored. If it is necessary to handle larger packets, modify the compiler define MAX_ICMP_DATA_LEN (in the header file "stacktsk.h").