Glossary

Q.931 is an ITU-T standard specification for basic call control. Q.931 is used in many networks such as ISDN. It is also part of the H.323 specification, where it is partially used. It is a message exchange protocol dealing with call setup procedures. Q.931 messages are encoded using a form ...

Quarter CIF: 176x44 pixelsA standard video format used in mobile video conferencing (3G-324M), where the phone’s processing power and power consumption (and the display) limit the video resolution. QCIF also requires only a quarter of the transmission bandwidth required for CIF video resolution.