Chapter 7 Signaling and Control Signaling extension of

Chapter 7 – Signaling and Control • Signaling – extension of control information from one network node or user to another over one or more network links • Signaling between user and serving node • Subscriber device and serving switch • Signaling between two network nodes • Switch to switch

Chapter 7 – Signaling and Control • Signaling domains

Chapter 7 – Signaling and Control • Channel Associated Signaling (CAS) or In band • Same circuit/path used for signaling and voice/data payload • Bandwidth of circuit reserved for signaling • Common-channel signaling (CCS) or out of band • Separate circuit/path/network used for signaling • Full bandwidth can be used for payload

Chapter 7 – Signaling and Control • CCS – out of band • ITU – Q. 931 used between private branch exchanges (PBX) • ISDN • Private corporate network • ITU – Signaling System No. 7 (SS 7) • Signaling between carrier networks

Chapter 7 – Signaling and Control • SS 7 Network functions • Call setup/disconnect – ISDN User Part (ISUP) • Database/services query – Transaction Capabilities Application Part (TCAP) • • Signal Transfer Point (STP) Signal Control Point (SCP) A link Point codes SCP A link Point code

Chapter 7 – Signaling and Control • Payload path vs Signaling path

Chapter 7 – Signaling and Control • SS 7 Messages Protocol

Chapter 7 – Signaling and Control • IP systems signaling – (voice over IP) • H. 323 protocol • • • ITU protocol Setup of calls via multimedia networks Video conf. Uses transport part of IP packet Complex protocol • Session Initiation Protocol (SIP) • Simple – text messages • • Requests and acknowledgements Header and Body • Peer to Peer • URL addresses

Chapter 7 – Signaling and Control

Chapter 7 – Signaling and Control • Intelligent Network