What Are Ping Utility Tools?

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Ping is the name of a standard software utility (tool) used to test network connections. It can be used to determine if a remote device (such as Web or game server) can be reached across the network and, if so, the connection's latency. Ping tools are part of Windows, Mac OS X, and Linux as well as some routers and game consoles.

Note: The term "ping" is also used colloquially by computer enthusiasts when initiating contact with another person via email, instant message or other online tools.

Ping Tools

Most ping utilities (sometimes called ping tools) use Internet Control Message Protocol (ICMP). They send request messages to a target network address at periodic intervals and measure the time it takes for a response message to arrive. These tools typically support options like:

  • How many times to send requests
  • How large of a request message to send
  • How long to wait for each reply

The output of ping varies depending on the tool. Standard results include:

  • IP address of the responding computer
  • Length of time (in milliseconds) between sending the request and receiving the response
  • An indication of how many network hops between the requesting and responding computers
  • Error messages if the target computer did not respond

The Ping of Death

In late 1996 and early 1997, a flaw in the implementation of networking in some operating systems became well-known and popularized by hackers as a way to crash computers remotely over the Internet.

The "Ping of Death" attack was relatively easy to carry out and very dangerous due to its high probability of success.

Technically speaking, the Ping of Death attack involved sending IP packets of a size greater than 65,535 bytes to the target computer. IP packets of this size are illegal, but applications can be built that are capable of creating them.

Carefully programmed operating systems could detect and safely handle illegal IP packets, but some failed to do this. ICMP ping utilities often included large-packet capability and became the namesake of the problem, although UDP and other IP-based protocols also could transport Ping of Death.

Operating system vendors quickly devised patches to avoid the Ping of Death, and it is no longer a threat on today's computer networks. Still, many websites have kept the convention of blocking ICMP ping messages at their firewalls to avoid similar denial of service attacks.