Based on IP technology, VoIP is favored for its extremely low price, though it severely erodes the market shares on voice service of PSTN operators and mobile operator.

• 摘要基于IP技术发展而来的IP电话业务因资费低廉而深受人们青睐，但也对传统的固定电话、移动电话语音业务造成严重冲击。