Introduction to Packet Voice Technologies Cisco Networking Academy Program
Tone telephone DTMF dialing Address Signaling • Rotary telephone • Pulse dialing
Packet Telephony vs. Circuit-Switched Telephony • More efficient use of bandwidth and equipment • Lower transmission costs • Consolidated network expenses • Increased revenue from new services • Service innovation • Access to new communications devices • Flexible new pricing structures
Real-Time vs. Best-Effort Traffic • Real-time traffic needs guaranteed delay and timing. • IP networks are best-effort with no guarantees of delivery, delay, or timing. • Solution is quality of service end-to-end.
Types of Local-Loop Signaling • Supervisory signaling • Address signaling • Informational Signaling
Foreign Exchange Trunks • Foreign Exchange Office • Connects directly to office equipment • Used to extend connections to another location • Foreign Exchange Station • Connects directly to station equipment • Used to provision local service
Types of Trunk Signaling • Loop start • Ground start • E&M Wink Start • E&M immediate start • E&M delay start
E&M Signaling • Separate signaling leads for each direction • E-lead (inbound direction) • M-lead (outbound direction) • Allows independent signaling