Ping

Ping refers to the classic ping utility and to the round-trip time it reports. The tool sends ICMP echo-request packets to a host and times how long the echo-reply takes to come back, giving you a direct read on latency. Results also reveal packet loss (replies that never arrive) and, across several probes, a sense of jitter. A typical line shows the host, the sequence number and the time in milliseconds. Some networks block ICMP, so a host that does not answer a ping is not necessarily offline.

Ping is the fastest sanity check when a connection feels slow: compare the round trip to a target before and after connecting through a proxy or VPN to see the added cost of the hop. Because ping uses ICMP rather than TCP or UDP, and many proxies only relay TCP, you often cannot ping through a SOCKS5 proxy directly — instead you measure the round trip with a real request to your target. Run several probes rather than one; a single figure can hide the variance that a short series makes obvious.

Because a single probe can mislead, always send several and read the spread, not just the average — a low mean can still hide packet loss and jitter that only a series reveals. When a host does not answer, remember it may simply block ICMP rather than be down. To gauge the delay a proxy adds when you cannot ping through it, time a real TCP request to your target instead, which reflects the path your traffic will actually use.