Voice and Video over IP

Topics Use Terminology specific to converged networks Explain VoIP Explain video over IP Describe VoIP and video over IP signaling and transport protocols Understand QoS

Terminology IP telephony: VoATM: VoDSL: FoIP: Video Conferencing Carries VoIP over TCP/IP network. VoATM: When using VoIP over an ATM network. VoDSL: When using VoIP over a DSL network FoIP: Fax using TCP/IP network. Video Conferencing Streaming video Webcasts IPTV

VoIP Applications and Interfaces Advantages: Lower costs New or enhanced features and applications Centralize voice and data network management

Works like a dial up connection. Analog Telephones Works like a dial up connection. Signals must be converted from digital to analog. One way is using a ATA (analog telephone adapter). Second way is connecting an analog telephone to a switch, router, or gateway capable of accepting analog voice signals, converting them into packets.

Analog Telephones Third is an analog-to-digital voice conversion device (IP-PBX). Fourth is the traditional phone connection to an analog PBX. Vonage

Softphones Internet phones Magic Jack Skype

Video over IP Applications and Interfaces Cisco Systems, the largest supplier of networking hardware, estimates that by 2011, 60% of the traffic carried by the Internet will be video traffic. Three Categories: Streaming video IPTV Videoconferencing

Two ways of providing this: Streaming Video YouTube is an example Two ways of providing this: Video-on-demand Live streaming video Examples of both Public and Private. YouTube videos TV episodes on Hulu.com Nov. 29, 2014

Best example of this is Telus TV. Set Top Boxes: IPTV Best example of this is Telus TV. Set Top Boxes: Google TV HD IPTV Nuclius Boxiee Celrun

This now provides a means of interaction. Videoconferencing This now provides a means of interaction. Telemedicine Tele-education Judicial proceedings Surveillance

Some functions performed include: Signaling Protocols Some functions performed include: Requesting a call Locating clients Acknowledging a request Managing ringing, dial tone, call waiting Detecting and reestablishing dropped calls Properly terminating a call

H.323 ITU standard that describes an architecture and a group of protocols for establishing and managing multimedia sessions on a packet-switched network. Key elements include: Terminal Gateway Gatekeeper (the nerve centre) MCU (multipoint control unit) Zone

SIP (Session Initiation Protocol) A protocol that performs functions similar to those performed by H.323 Modeled on the HTTP protocol. SIP’s capabilities are: Determining the location of an endpoint. Determining the availability of an endpoint. Establishing a session between the endpoints Negotiating features of a call Changing features of a call

Transport Protocols RTP (Real-Time Transport Protocol) RFC1889, at the application layer relies on UDP at the transport layer. RTCP (Real-Time Transport Control Protocol) RFC 3550, provides feedback on the quality of a call. Although RTP and RTCP provide information about the packet order, loss, and delay, they cannot correct transmission flaws

QoS Assurance This measures how well a network service matches its expected performance. Three techniques standardized by IETF RSVP (Resource Reservation Protocol) RFC 2205 a transport lay protocol DiffServ (Differentiated Service) Because of its simplicity and low overhead, it is better suited to large networks. MPLS (Multiprotocol Label Switching) Contains information about where the router should forward the packets.