The Future of Voice over Internet Protocol

1. The Future of Voice over Internet Protocol Presenter: Scott Martin April 12, 2007

2. Introduction • What is Voice Over Internet Protocol (VoIP)? • The two-way transmission of audio over a packet-switched IP network. • When used in a private intranet or WAN, it is generally known as 'voice over IP,' or 'VoIP.' • When the transport is the public Internet or the Internet backbone from a major carrier, it is generally called 'Internet telephony’.

3. Introduction • Voice Over Internet Protocol (VoIP) • History • Implementation • Service Types • Benefits • Drawbacks • Current and Projected Use

4. History of VoIP • Network Voice Protocol • Created in 1973 by Danny Cohen at USC • Project Goals • Wanted to create digital high-quality, low-bandwidth, secure voice handling capability • Control Protocol • Data Transport Protocol

5. Circuit Switching • Current Phone Systems • Dedicated line with a constant connection • Originally very expensive • Each call transmits at 64 kilobits per second • 64 kbps x 2 directions = 128 kbps • 128 kbps = 16 kilobytes per second • During a 10 minute call, about 10 MB • Highly inefficient

6. Circuit Switching • Example: Circuit Switching

7. Packet Switching • VoIP Phone Systems • Connection only long enough to send a packet of information • Thousands of possible paths for packet to go • Network uses cheapest and least congested paths • Quality of Service (QoS) • A 10 minute call transfers only about 2 MB

8. Packet Switching • Example: Packet Switching

9. Quality of Service (QoS) • Defined in the International Telecommunication Union standard X.902 • A set of quality requirements on the collective behavior of one or more objects. • Control mechanisms to provide different priorities to different users or data flows • Important for real-time streaming applications

10. VoIP Implementation • Sender picks up the phone • Analog telephone adapter (ATA) • Data converted by a codec • Soft Switch • Receiver picks up ringing phone • Data transfer during calls is handled by current internet infrastructure

11. Analog Telephone Adapter (ATA) • Converts audio between analog and digital signals • Need one on each end of the call • Sends signal to handle connect and disconnect

12. Codecs • Coder-decoder or codecs • Conversion from analog audio signal to digital signal • Most common codec is the G.729A • sampling rate of 8,000 times per second • Conjugate-structure Algebraic-code-excited Linear Prediction algorithm (CS-ACELP) • Responsible for the large gap in performance

13. Soft Switches • Database mapping program • Endpoint-to-Endpoint • Location • Phone Number • IP address • Allows phones, computers, and WiFi phones to work together

14. Industry Protocol Standards • H.323 Protocol Suite • Main flaw – not designed for VoIP

15. Industry Protocol Standards • Session Initiation Protocol (SIP) • Smaller, more efficient • Designed specifically for VoIP • Handles • User location • User capabilities • User availability • Call setup • Call handling

16. VoIP Service Types • Home Phones • Requires an ATA • Usually provided for free • IP Phones • ATA technology built in • Ethernet Phones • WiFi Phones • Computer-to-Computer calls

17. Computer-to-Computer VoIP • Simplest and cheapest way to use VoIP • Requires • Microphone • Speaker • Sound card • Broadband internet • Costs: Software and ISP service • Calls: Free • Example: Skype Download Service

18. Benefits • Uses technology already in common use • Cost • Bundled Services • Caller ID • Voice Mail • Call Waiting • Call Forwarding • Many Others • Long Distance and International Rates

19. Benefits Cost of Calls Made from US to Foreign Countries

20. Drawbacks • 911 Emergency Calls • Dependence on Wall Power • Latency issues, jitter, and packet loss • Viruses, worms, and hackers • Integration with land-line dependant hardware • DVRs, digital television service, and home security systems

21. Drawbacks • Security • Problems sending faxes • Dependence on Internet Service Providers • Requirement of broadband connectivity • WiFi hotspot dependence

22. Current and Projected Use • Roughly 6 million in US in 2006 • Expected to climb to 24 million by the end of 2008 • Increase in service providers • Traditional phone companies • At&T, Sprint, Nextel, Time Warner • VoIP companies • Skype, Vonage, VoIP Inc.

23. Conclusion • VoIP will be a dominate force in the 21st century • Probably at least another 10 years before possibly replacing current phone systems • If the current flaws are fixed sooner rather than later, it could be much sooner than a decade

24. References • Wikipedia. “Network Voice Protocol”. March 2007 (http://en.wikipedia.org/wiki/Network_Voice_Protocol) • Valdes, Robert. HowStufWorks. “How VoIP Works”. May 2001 (http://electronics.howstuffworks.com/ip-telephony.htm) • Protocols.com. “Voice Over IP Protocols”. March 2007 (http://www.protocols.com/pbook/VoIP.htm) • Bell, Michael. “Ways to Use VoIP”. 2007 (http://ezinearticles.com/?Ways-to-Use-VoIP-Technology&id=125070) • VoIP.com. 2007 (http://www.voip.com/) • AT&T.com. “AT&T International Rate Finder”. 2006 (http://www.consumer.att.com/global/english/international.html) • BellSouth.com. “International Calling Plan Rates”. (http://www.bellsouth.com/consumer/bsld/icpRates.html) • Qwest. “Qwest OneFlex International Rates”. 2007 (https://cvoip.qwest.com/oneflex/portal/residential/products/voip/ratesl) • Verizon. “Country Code and International Rate Finder”. 2007 (http://www22.verizon.com/ForYourHome/LD/WorldCaller.asp)[10] FCC Consumer & Governmental Affairs Bureau. “Voice Over Internet Protocol”. June 2006 (http://www.fcc.gov/voip/) • Wikipedia. “Voice Over IP”. March 2007 (http://en.wikipedia.org/wiki/Voip) • New Paradigm Resources Group. ISP-Planet.com. “Executive Summary, VoIP Report 3rd Edition”. December 2006 (http://www.isp-planet.com/research/2006/nprg_voip_summary.html)