1. Jajah Speaker: Yan-Shiang Wang Date: 2007.05.28

2. 2 Classic Caller Callee PBX PSTN Signaling Voice

3. 3 Voice over IP CallerCallee VoIP Proxy Internet VoIP Proxy Internet Signaling Voice

4. 4 Jajah Usage  Make a phone call through web-page  Caller picks up the phone  Callee picks up the phone Play a middleman role

5. 5 User Interface

6. 6 Flow chart PSTN CallerCallee Internet VoIP Proxy PBX Internet/PSTN Caller’s PC Internet 1 2 2 3 3 3 1 Signaling Voice

7. 7 Advantage Use original hard phone Use original phone number The only restriction is caller needs to use computer at initial of call  Solution: use smartphone

8. 8 Disadvantage This is not in the inherent free for charge

9. 9 Reference http://www.jajah.com