The sesman tools sesrun and sesadmin now use the separate
authentication/authorization (AA) interface introduced to
sesman by the previous comment.
sesrun can use either password or UDS authentication. With some
limitations, this can allow for automatic creation of sessions for local
users without a password being needed.
sesadmin now operates using UDS logins only and so a username and
password are not required. To use sesadmin for another user, use
su/sudo/doas to authenticate as the other user.
The TCP socket implementation of sesman has a number of limitations,
namely that it is affected by firewalls, and also that determining the
user on the other end requires a full authentication process.
The advantage of the TCP socket is that sesman and xrdp can be run on
separate machines. This is however not supported by the xorgxrdp
backend (shared memory), and is insecure, in that passwords are sent
in-the-clear, and the connection is susceptible to MitM attacks. This
architecture has been deprecated in release notes since xrdp v0.9.17,
and although it will continue to be supported in any further releases
in the x0.9.x series, it will not be supported in the next major
version.