WHAT IS ICMP

What is ICMP ??

ICMP stands for Internet Control Message Protocol. It is a network layer protocol used in the Internet Protocol (IP) suite, primarily for diagnostic and error-reporting purposes. ICMP is used by network devices, like routers and hosts, to communicate error information and status updates to other devices on the network.

ICMP == 네트워크 프로토콜 주요 용도는 오류 리포팅이며, 네트워크 단말에서 사용됨 (such as 라우터, …) 오류를 알리기위한 용도 + 상태를 알리기 위한 용도로 사용됨.

특징

오류 리포트

Error Reporting: ICMP is often used to report errors in packet delivery. For example, if a router encounters a problem forwarding a packet, it may send an ICMP message back to the source indicating the issue.

패킷 전달시 오류를 리포팅 함
예로 라우터가 패킷을 전달할 때 그것은 ICMP 메세지를 발급전 상태로 돌린다.

네트워크

Network Reachability: ICMP includes features such as the “ping” command, which is used to test network reachability and measure round-trip times between hosts. Ping sends ICMP Echo Request messages to a destination host, and the host responds with ICMP Echo Reply messages if it is reachable.

ICMP는 여러 기능을 포함하는데 그 중 ping 명령을 포함한다.
핑을 목적지 host까지 전송하며 목적지로부터 요청이 도달했는지 여부를까지 응답받는다.

트러블슈팅

Network Troubleshooting: ICMP messages are also useful for network troubleshooting. They can provide information about network congestion, unreachable destinations, time-to-live (TTL) exceeded, and other network-related issues.

ICMP 메세지들은 네트워크간 트러블슈팅에 유용함.
많은 정보들을 제공함 (혼잡도, 목적지도달여부, TTL 초과여부…) + @(다른 네트워크와 연관된 이슈들)

관리

Control and Management: ICMP includes various message types for network control and management purposes, such as Router Advertisement and Router Solicitation messages for IPv6 autoconfiguration, Redirect messages for optimizing routing paths, and Timestamp Request and Reply messages for clock synchronization.