The X.25 Relay module resides in the application layer of the
    Digital Network Architecture (DNA). It interfaces with the X.25
    Access module to receive an incoming switched virtual call and then
    makes an outgoing call through the X.25 Access module. Facilities
    also exist for relaying permanent virtual circuits (PVCs).

    The x25 relay entity accepts an incoming call from one client and
    redirects it to another client.