VoIP – Case Studies Duncan MacAuslan Task Coordinator - VoIP ITP Training September 2006

IP Layered Model Service Provider End user purchased applications, VSP * - theoretically there is no session layer in the IP model, split here for clarity. ADSL, Ethernet, WiFi TCP/UDP IP SIP/H.323, G7xx VoIP HTTPToIPetc.Application ISP/CSP Carrier Session* Transport Internet Network Access LayerProtocols

Three carrier models PSTN PBX Router/GW IP WAN Soft-Switch Router IP WAN Application Servers PBX Traditional PSTN PSTN core replaced by packet switching Full end to end IP network – the NGN Where we are now! Transitionary mixture

VoIP Models Peer to peer Conventional Message Phone out from IP to PSTN Phone in from PSTN to IP – DID – Extension

Connecting a traditional phone to VoIP Phone/USB ‘dongle’ Broadband Wireless Internet ATAs ADSL or cable ATA – analogue telephone adaptor

IP handset connections Broadband Wireless Internet Connected to PC by sound card, USB or ethernet ADSL or Cable to Internet IP phones connected directly to local ethernet

Analogue Telephone Adaptor Internet Router PSTN PSTN used when no connection to internet VoIP pathway LAN

VoIP calls to users on same VSP network Internet Fred calls VoIP user Jill Routed across internet to VSP’s network VSP’s softswitch refers call to SIP server URI to find Jill’s current IP address. SIP server then drops out. Call is routed across VSP’s network to internet gateway closest to Jill

Outbound one-way VoIP service Internet PSTN If gateway in Australia caller usually has nominated a local call zone. If gateway overseas caller must dial full e.164 code eg even if called party is next door. The gateway could be anywhere in the world depending on best tariffs. If gateway overseas, 000, if allowed, will arrive on international trunk CLI will be that of a line on gateway, if overseas eg , not necessarily identifying caller. SIP used to map caller’s IP address and URI to gateway phone number

Inbound PSTN to VoIP – DID model Internet PSTN VoIP user is allocated PSTN number eg Calling party dials VoIP user using PSTN number; routed across PSTN to VSP’s incoming gateway VSP’s softswitch refers call to SIP server to map PSTN to URI and current IP address. SIP server drops out. Call is routed across gateway to internet

Inbound PSTN to VoIP – extension model Internet PSTN VoIP user allocated a extension eg Caller dials VSP’s gateway using PSTN number Routed across PSTN to VSP’s incoming gateway. When call established caller dials ‘extension’ using DTMF VSP’s softswitch refers call to SIP server to map extension to URI and current IP address. SIP server drops out. Call is routed across gateway to internet

VoIP to VoIP PSTN VSP1 VSP2 Internet Red line where VSP1 user must use PSTN to call VSP2 user Phone outPhone in eg Skype Green line shows how a Skype user calls a VSP2 user Purple shows how peering will avoid the PSTN – the NGN solution

Some IP telephony examples Operator 1 targeted at any broadband customer nationally launched early 2005 new broadband churn processes, power supply notice to users, number allocation

Operator 2 Wireless broadband voice Sydney and Melbourne metro coverage Assessed numbering options, expected geographic but longer term will explore mobility capability, radio links should create greater customer awareness of power issue Endorsed third party VoIP provider over own network

Operator 3 Existing experience with customers and billing in cellular market Mass market (retail outlets and advertising) via any broadband link includes CE (process B) FAQs include a number of quality and performance warnings, numbers via 3 rd party ISDN aspiring to CCS7

Operator 4 Triple play over cable with voice broadband and Pay TV Regional Victorian focus Agreed CE and customer advice warnings re – power, – temporary exemption from portability because of interface, – highly localised pricing attraction