ITU-T Q.721-1988
FUNCTIONAL DESCRIPTION OF THE SIGNALLING SYSTEM No. 7 TELEPHONE USER PART (TUP)

Standard No.

ITU-T Q.721-1988

Release Date

1988

Published By

International Telecommunication Union (ITU)

Latest

ITU-T Q.721-1988

Scope

Use of Signalling System No. 7 for telephone call control signalling requires

ITU-T Q.721-1988 history

• 1988 ITU-T Q.721-1988 FUNCTIONAL DESCRIPTION OF THE SIGNALLING SYSTEM No. 7 TELEPHONE USER PART (TUP)