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Voice over IP IP Raj Jain The Ohio State University Columbus, OH 43210 Jain@CIS.Ohio-State.Edu http://www.cis.ohio-state.edu/~jain/ Raj Jain 1 Overview Sample Products and Services 13 Technical Issues 4 Other Issues H.323 Standard Session Initiation Protocol (SIP) Raj Jain 2 Scenario 1: PC to PC IP Network Need a PC with sound card IP Telephony software: Cuseeme, Internet Phone, ... Video optional Raj Jain 3 Scenario 2: PC to Phone IP Network Phone Network Gateway Need a gateway that connects IP network to phone network (Router to PBX) Raj Jain 4 Scenario 3: Phone to Phone Phone Network IP Network Gateway Phone Network Gateway Need more gateways that connect IP network to phone networks The IP network could be dedicated intra-net or the Internet. The phone networks could be intra-company PBXs or the carrier switches Raj Jain 5 Sample Products VocalTec Internet Phone: PC to PC. Microsoft NetMeeting: PC to PC. Free. Internet PhoneJACK: ISA card to connect a standard phone to PC. Works with NetMeeting, InternetPhone etc. Provides compression. Internet LineJACK: Single-line gateway. Micom V/IP Family: m Analog and digital voice interface cards m PC and/or gateway Raj Jain 6 Products (Cont) PBX PC w V/IP S/w m Gateway Router IP Network Features: q Compression q Phone number to IP address translation. q Supports RSVP. q Limits number of calls. Raj Jain 7 Products (Cont) VocalTec Internet Telephony Gateway: m Similar to Micom V/IP m Interactive voice response system for problem reporting m Allows WWW plug in m Can monitor other gateways and use alternate routes including PSTN m Sold to Telecom Finland. New Zealand Telecom. Lucent's Internet Telephony Server: Gateway| Lucent PathStar Access Server Raj Jain 8 Products (Cont) CISCO 2600 Routers: Voice interface cards (VICs) Reduces one hop. Baynetworks, 3COM, and other router vendors have announced product plans PBX Router IP Network PC Raj Jain 9 Sample Services IDT Corporation offers Net2Phone, Carrier2Phone, Phone2Phone services. Global Exchange Carrier offers international calls using VocalTec InternetPhone s/w and gateways Qwest offers 7.5¢/min VOIP Q.talk service in 16 cities. ITXC provides infrastructure and management to 'Internet Telephone Service Providers (ITSPs)' America On-line offers 9¢/min service. AT&T announced 7.5¢/min VOIP trials in 9 US cities Raj Jain 10