samselse'u lujvo

se2=sk1 is a client [computer] served by server [computer] se1 with service se3 (activity).

Networking is implied. Note that the term “client” is used quite broadly in English, even if narrowed down to the networking sense. For “samselse'u”, the x1 and x2 places are only used to refer to the involved computers. See also: samse'u

In notes:

se1=sk1 is a server [computer] serving client(s) [computer(s)] se2 with service se3 (activity).