This module implements the `/ipfs/ping/1.0.0` protocol.
The ping protocol can be used as a simple application-layer health check
for connections of any [`Transport`] as well as to measure and record
round-trip times.
# Usage
The [`Behaviour`] struct implements the [`NetworkBehaviour`] trait. When used with a [`Swarm`],
it will respond to inbound ping requests and as necessary periodically send outbound
ping requests on every established connection. If a configurable number of consecutive
pings fail, the connection will be closed.
The [`Behaviour`] network behaviour produces [`Event`]s, which may be consumed from the [`Swarm`]
by an application, e.g. to collect statistics.
> **Note**: The ping protocol does not keep otherwise idle connections alive
> by default, see [`Config::with_keep_alive`] for changing this behaviour.
[`Swarm`]: libp2p_swarm::Swarm
[`Transport`]: libp2p_core::Transport