Network Connection

Types of connections

Xpra supports 3 main types of connections:

• unix domain socket connections. From the same machine only - potentially as a different user. This is obviously restricted to Unix like systems. When using this type of direct connection, you should also be using mmap for maximum speed (which should be enabled by default). For connecting to a different user, you may need to use the socket-dir option to place the socket in a public location, and maybe also mmap-group to make the socket accessible to other users.

When starting a server, a socket is automatically created for it by default.

• TCP connections using the bind-tcp option. May be specified more than once to bind to multiple ports or IPs, supports IPv6. These can be secured with a password-file, in which case you probably want to enable encryption to prevent some MITM attacks.
• SSH connections: this type of connection uses a SSH as transport to connect to the unix domain socket. (forwarded using the hidden xpra sub-command "_proxy").

On Unix-like systems you may need an SSH_ASKPASS utility to be able to enter your password or passphrase.

General Network Information

The performance of xpra may well be limited by your network connection speed, and may well be affected by ​bufferbloat. Some network information can be obtained from the "Session Info" dialog or via the "xpra info" command:

$ xpra info | egrep -i "network|latency"
(..)
client.latency.50p=3
client.latency.80p=3
client.latency.90p=3
client.latency.absmin=1
(..)

Investigating network performance and bottlenecks in detail is beyond the scope of this document. For Linux system, ​Queueing in the Linux Network Stack is recommended reading.