pluggable transport (sometimes also called ‘transport’)¶

Pluggable transports obfuscate network traffic.

Specifically, pluggable transports transform the Tor traffic flow between the client and the bridge. This way, censors who monitor traffic between the client and the bridge see innocent-looking transformed traffic instead of the actual Tor traffic.

pluggable transport proxy¶

Pluggable transport proxies are programs that implement pluggable transports. They also implement the networking system that a pluggable transport needs (so that it can proxy data).

obfsproxy¶

obfsproxy is a pluggable transport proxy written in C. It implements the obfs2 pluggable transport.

upstream/downstream¶

The upstream side of a pluggable transport proxy is the side that communicates with Tor. Upstream data is non-obfuscated.

The downstream side of a pluggable transport proxy is the side that communicates with the other pluggable transport proxy. Downstream data is obfuscated.

client-mode / server-mode¶

A pluggable transport is a client if it has a Tor client in its upstream side.

A pluggable transport is a server if it has a Tor bridge in its upstream side.

external-mode proxy¶

A pluggable transport proxy is in external-mode if the user explicitly configures it using its command-line interface.

managed-mode proxy¶

A pluggable transport proxy is in managed-mode if it’s launched and managed by Tor using the managed-proxy configuration protocol. The managed-proxy configuration protocol is defined in the pluggable transport specification.

pyptlib¶

pyptlib is a library that implements the managed-proxy configuration protocol and makes it easier for application to be used as managed proxies.

extended orport¶

Extended ORPort is an non-implemented feature of Tor that allows a pluggable transport proxy to communicate with Tor in real-time.