A connection is established when two end points use a protocol to establish connection through use of various methods such as segment numbering to ensure data delivery, and handshaking to establish the initial connection. Connections can be stateful because they record information about the state of the connection. Persistent connections reduce request latency because the end points do not need to re-negotiate the connection multiple times, but instead just send the information without the extra overhead. By contrast, connectionless communication does not keep any information about the data being sent or the state. It is based on an autonomous response/reply that is independent of other responses/replies that may have gone before. One example of connectionless communication is IP.

Benefits of connections over connectionless include being able to split data up over multiple packets, the data allows for a best-effort approach, and once the connection is established subsequent packets are not required to contain the full addressing information which saves on bandwidth. Connections are often reliable network services since acknowledgements can be sent when data is recieved.