This class implements a general plug proxy, and is capable of optionally disabling data transfer in either direction. Plug proxy reads connection on the client side, then creates another connection at the server side. Arriving responses are sent back to the client. However, it is not a protocol proxy, therefore PlugProxy does not implement any protocol analysis. It offers protection to clients and servers from lower level (e.g.: IP) attacks. It is mainly used to allow traffic pass the firewall for which there is no protocol proxy available.

By default plug copies all data in both directions. To change this behavior, set the copy_to_client or copy_to_server attribute to FALSE.

Plug supports the use of secondary sessions. For details, see Section 2.2, Secondary sessions.