Basics of IP Telephony

Sam Lutgring Director of Informational Technology Services Calhoun Intermediate School District

What are we here to talk about?

Central Office

Evolution of Communications

Basic Terminology (1 of 3)

        PSTN – Public Switched Telephone Network PBX – Private Branch Exchange CO - Central Office Centrex or Hosted/Virtual PBX POTS – Plain Old Telephone Service FXO - Foreign Exchange Office FXS - Foreign exchange Station Channel Bank

Basic Terminology (2 of 3)

        Digital Circuit T1 – Digital Network Interface PRI – Primary Rate Interface IP - Internet Protocol Convergence or multiservice networking Unified Messaging VoIP – Voice Over Internet Protocol VoIP PBX

Basic Terminology (3 of 3)

       VoIP Gateway VoIP Service provider SIP - Session Initiation Protocol CODEC G.711 ulaw IVR – Integrated Voice Response PoE – Power Over Ethernet

Basics of a PBX

  Establishing and maintaining connection (call) between end devices All the call features – Conferencing – IVR – Transfer – Call pick-up

What is VoIP?

 Voice Over Internet Protocol – Allows voice to become simply another piece of data (packet) riding the network – Takes advantage of existing data networks by combining components of data and voice networks – Transports voice packets using Internet Protocol (IP)

What is VoIP?

 Both a technology and a service – The technology is Internet Protocol (IP) allowing the packets to be transferred across the data network – The service is the voice portion, allowing voice to be transferred across the network

What is VoIP?

 Three Common Types – Geek-to-Geek – Gateway/Switch-to-PSTN – PSTN-to-PSTN

Why is it Catching On?

   Integration and application management One physical layer one infrastructure (single wiring closet) – Simpler and less expensive to install and maintain – Leverage common data network and equipment Simplification – Single network management system – Moves, adds, and changes for phones – Deployments

Why is it Catching On?

     Flexible IP address assignment Increased system redundancy Backup consolidation Customized end user experience Cost (in some cases)

What is the Future?

Cell Phone IP Network PDA WIFI (Soft Phone) WIFI Gateway Video IP PBX IP Phone

What do I need to know?

      Requires a robust data network Network outages/issues impact voice network Redundancy/Failover Emergency Services Connecting to traditional phone services Voicemail/e-mail integration

QUESTIONS?

www.voip-info.org