03/02/2005 David Keffer UOIT Student #100257682 Internet Telephony CURS4161 Curriculum Studies – Computer Studies II David Keffer UOIT Student #100257682

03/02/2005David Keffer

UOIT Student #100257682

Internet Telephony

CURS4161Curriculum Studies – Computer Studies IIDavid KefferUOIT Student #1002576823rd February, 2005

Internet



What is Internet telephony?

• Internet telephony is the transport of telephone calls over the Internet

• Calls can use traditional telephony equipment, multimedia PCs, or dedicated terminals

• Calls can be either fully or only partially carried over the Internet

• Call quality varies with the speed of the Internet connection and computers of both parties, traffic on the net, and the software used



Types of Internet Telephony

• PC to PC• call is initiated by either PC• pure IP scenario, best used with a fast,

dedicated Internet connection• requires a multimedia PC (speakers

and microphone)• software is usually free, often included

with chat software

Internet




Internet

Gateway

PSTN

• PC to telephone• call is initiated by the PC• the Internet call is converted to a PSTN

call by a gateway, located as near to the callee as possible, to minimize the cost

• costs charged by the gateway operator to cover maintenance and other costs

• software is usually free




• Telephone to telephone• call is initiated by either telephone• the telephone call is converted to IP

(Internet) by a gateway, located as near to the caller as possible, and then converted back to PSTN by another gateway near the callee

• costs charged by both gateway operators

• specialized equipment may be required

Internet

Gateway

PSTN

Gateway

PSTN




• Telephone to PC• much less common scenario• essentially the reverse of the PC to

telephone scenario, with call initiated by the telephone

• costs charged by the gateway operator• this service provided by gateway

operator, and may require special equipment

Internet

Gateway

PSTN



Internet Telephony Software

• Skype• MSN Messenger• MS NetMeeting• CoolTalk• CuSeeMe • DialPad• Net2Phone

Most of these services provide free PC to PC calling. Many also provide typed chat and PC to phone service. CuSeeMe and NetMeeting also provide videoconferencing. DialPad allows free calling within the US from their web site, and does not require separate software. CoolTalk provides a shared whiteboard for sharing and marking up graphic images in collaboration.

• Several good Internet telephony software solutions are available (all incompatible with each other!):



Skype, v1.1



Skype v1.1 Features

• Available from http://www.skype.com• Currently showing 59.8 million downloads

(up from 55.7 less than a week ago), and 4.5 billion ‘minutes served’ (up from 4.4)

• Multi-platform, including Windows, Mac OSx, Linux and PocketPC

• Free PC to PC, chat, and conference calling• Very reasonable rates to call landline or

cellular phones worldwide



Skype v1.1 Features

• File transfers up to the file size allowed by the OS! (usually between 2 and 4 Gb)

• Communications are encrypted end-to-end • Not server-based, but true peer-to-peer

telephony• Works through most firewalls• Excellent sound quality – this is one of the

main areas of development• Spy-ware and ad-ware free!



Skype: Start Tab



Skype: Making a Call



Skype: Talking



Skype: Conference Call



Skype: Call Regular Phones



Skype: File Transfer



Skype: Chat



Skype: SkypeOut Rates

• SkypeOut ‘Global’ Rate = €0.017 /minute• Argentina (Buenos Aires), Australia, Austria,

Belgium, Canada, Canada (mobiles), Chile, Denmark, France, Germany, Ireland, Italy, Mexico (Mexico City, Monterrey), Netherlands, New Zealand, Norway, Portugal, Russia (Moscow, St. Petersburg), Spain, Sweden, United Kingdom, United States (except Alaska and Hawaii), United States (mobiles) and last but not least: Vatican.

• Other rates available at http://www.skype.com/products/skypeout/rates/all_rates.html



Conclusion

• Factors improving Internet telephony are• faster and more powerful PCs• improved data compression techniques• faster broadband Internet access• improved audio and video codec technology

• According to some studies, by 2010• at least 50% of North Americans will use the

Internet daily, and • 28% of international voice communication will

take place over the Internet



Demonstrations



References

• Internet Telephony Overviewhttp://www.iptel.org/info/

• Webopedia: Internet Telephonyhttp://www.webopedia.com/TERM/I/Internet_telephony.html

• Internet Telephonyhttp://www.cse.ohio-state.edu/~jain/cis788-97/ftp/internet_telephony/index.htm

• Conferencing: Talk is Cheap With Internet Telephonyhttp://www.learnthenet.com/english/html/64teleph.htm

• Kevin’s Internet Telephony Depothttp://kevin.hipplanet.com/



Presentation Survey

• If you have a moment, please complete the presentation survey at

http://www.getfast.ca/students/index.cfm?

Randomcourse=83109742.0 (password=skype)

Thank you!

Documents

03/02/2005 David Keffer UOIT Student #100257682 Internet Telephony CURS4161 Curriculum Studies – Computer Studies II David Keffer UOIT Student #100257682