MSTP private line service

private line service

private-line service(PLS)

teletypewriter service， private-line

teletypewriter service，private-line

Actinoid private line

ATM private-line

carrier private line

enhancement private service

multischedule private line

private line

private line access

private line arrangement

private line auto ring down

private line interconnection service

private line teletypewriter

private line， dedicated line

private voice-band network

private-line