ICMP Ping
Measures network latency and server reachability using ICMP ping, the most basic indicator of server availability.
What is ICMP?
ICMP (Internet Control Message Protocol) is a network-layer protocol used by network devices to send error messages and operational information. Unlike TCP or UDP, ICMP is not used to exchange data between systems — it is a diagnostic and control protocol.
The most familiar ICMP operation is the echo request / echo reply pair, commonly known as "ping". When you run ping example.com, your machine sends an ICMP Echo Request packet; if the destination is reachable, it responds with an ICMP Echo Reply. The round-trip time is the latency. ICMP is defined in RFC 792; its IPv6 counterpart ICMPv6 is in RFC 4443.
What is an ICMP Ping Check?
DigiPulse sends ICMP Echo Request packets to your server from our monitoring nodes and measures the round-trip time and packet loss. This is a network-level check — it tells you whether the server is reachable at the IP layer, regardless of what applications are running.
What DigiPulse Measures
Latency (ms) — Round-trip time from our monitoring node to your server.
Packet loss — Percentage of ping packets that did not receive a response.
Reachability — Whether the server responds at all.
Why It Matters
A ping check detects network-level issues that other checks might miss — such as routing problems or network saturation. High latency often precedes a full outage, making this an early warning signal for infrastructure problems.