MAEDS 45th Annual Conference

October 14 -16, 2009

IP Telephony for Poets

Sam LutgringDirector of Informational Technology

ServicesCalhoun Intermediate School District

MAEDS Board of Directors

Introduction

Voice Over Internet ProtocolAllows voice to become simply another piece of

data (packet) riding the network.A telephony system that takes advantage of

existing data networks by combining components of data and voice networks

Transports voice packets using Internet Protocol (IP)

What is VOIP?

VOIP is both a technology and a serviceThe TECHNOLOGY is IP(Internet Protocol)

which allows 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 TypesGeek-to-Geek Gateway/Switch-to-PSTN PSTN-to-PSTN

Two “Flavors”Application BasedNetwork Based

What is VOIP?

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File Server

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PSTN

Traditional Data and Voice Networks

File Server

VOIP Gateway

PSTN

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Converged Network

One physical layer one infrastructure (single wiring closet) Simpler and less expensive to install and maintain Leverage common data network and equipment

Single network management systemSimplifies moves, adds, and changes for phonesChoice of phone powerFlexible IP address assignmentIncreased system redundancy

Why Should I Care?

VoIP GatewayConverts the voice call traffic from traditional

telephony to IP (data network) and vice versa VoIP PBX (Private Branch Exchange)

A PBX that natively supports Voice over IPVOIP Service provider

Company delivering traditional voice service by utilizing VOIP

IP (Internet Protocol)The universal language of computers

PSTNPublic Switched Telephone Network

What do the BUZZ words mean?

Convergence (multiservice networking)Marketing terminology used to describe the

utilization of one network facility to deliver multiple services; usually data, voice, and video.

Unified Messaging Integration of messaging and communication (e-

mail, voicemail, SMS, fax) into a single interfaceDigital Circuit

Delivery of voice services through a digital line. Usually a T1 with ISDN signaling in the US.

Analog Circuit/POTSTraditional analog line delivered to home or business

What do the BUZZ words mean?

What standards should I be aware of?Make sure vendor supports OPEN

STANDARDS.G.711 ulaw is the standard Codec used in

the US by carriers.SIP (session initiation protocol) is a

commonly used and supported VoIP peer-to-peer protocol.

H.323 another format used to define call control and setup.

What are some common solutions?Add IP support to existing PBXVoIP gatewayVoIP PBX

FEATURE TRADITIONAL VOIP

Power Multiple (redundant) power supplies

Multiple power supplies with multiple sources

Call Processing Redundant Processors on the same system

Multiple servers acting in a cluster

Modularity One system with multiple components

Multiple systems with isolated failures

Backups Backup of internal system, weekly tape rotation

Mirrored system drives, utilize existing server backup architecture

Administration Specialized mapping Web interface or text files

System Software

Proprietary Standards based

Feature Comparison

Feature ComparisonFEATURE TRADITIONAL VOIP

System Expansion

Major cost and usually replace system

Additional license or hardware

User Customization

Limited if any Web interface

Additional Phone Functionality

Replace Phone Software upgrade

Adds Define port in system, hard wire phone into port

Add extension and phone

Moves Reconfigure port and change wiring infrastructure

Plug the phone in somewhere else

Must have a robust data networkAll your eggs in one basket/networkNetwork outages/issues impact voice network

What are the Down Sides?

Always Remember E911/911E911 requires that the calling phone can

be tracked back to an addressPotential Issues

Multiple buildings routed out the same LEC (local exchange carrier) infrastructure.Work with LEC to identify a specific outbound

channels for each building to route 911 calls.Place analog lines with switch in each building for

emergency call routing only.VPN users calling on soft phones from home.

Train staff not to do this.Contract with a VoIP provider rather then

traditional LEC.Make sure this is addressed in your contract.

Traditional Desk Phone Grandstream/Polycom/Sonoma/Cisco

Soft phoneComputer Client

Low Cost Analog PhoneSame as your house

What about Phones?

Powering the phonesPOE (Power Over Ethernet)

POE switches capable of delivering powerPowered patch panel inserted between existing

switch and end devicesAC power adapter to wall socket

Digital InterfaceMultiport PCI cardUsually T1 interface with ISDN signaling

Analog Interface4-8 port PCI cardsChannel Bank with 8/12/16/24/32/40 portsFXO (Foreign exchange Office)

FXO interface receives power and receives ring signalPlug the Central Office in here

FXS (Foreign exchange Station)FXS interface provides power and generates ring

signalsPlug a handset in here

How do I talk to Grandma?

Data NetworkRedundancy/FailoverEmergency ServicesConnecting to traditional phone servicesVoicemail/e-mail integration

What do I need to consider?

AsteriskCiscoLucentSiemens… the list goes on

Where do I get it?

www.voip-info.orgWiki that provides excellent information on

VOIPwww.digium.com

Makers of voice processing cardswww.thevoipconnection.com

Great source for hardware

Where can I find out more?

What is the Future?

Any device to any device on any network

WIFIGateway

IP PhoneIP PBX

FaxGateway

SmartPhone

Video

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DesktopLaptop

(Soft Phone)IP Network

PDAWIFI

CellPhone