1. The first Internet-telephony software, Internet Phone, supported PC–to–PC and telephone-to-telephone voice calls via the Internet.

2. The current reliability and sound-quality problems of Internet telephony are attributable to limitations in Internet bandwidth and compression technology.

3. As a packet-switched or connectionless network, the Internet decreases the chances of packet loss for a voice call.

4. To date, most developers of Internet-telephony software and vendors of gateway servers have used the same speech-compression protocols.

5. The ITU has ratified a standard for voice, data, and video transmission over IP–based local area networks.

6. ITU's H.320 standard defines the protocols for transporting voice, data and video over:

7. The G.723.1 specification for audio codecs, recommended by the VoIP Forum, requires:

8. Internet-telephony directories enable:

9. In the near term, the market segment expected to be the biggest driver for VoIP telephony is:

10. The public Internet will be able to transport voice calls reliably and with high quality when: