Internet Telephony, the use of corporate networks for telephone and facsimile communications will save businesses $1bn a year, and cause US telco revenues to fall by 4%, by the year 2004, according to industry analysts Forrester Research Inc. It sees three markets as particularly well suited to Internet Telephony, international voice communications where lower quality is acceptable, faxing, because it’s delay resistant, and intra- company voice traffic, as the corporate networks will be of low delay. Forrester sees the established telcos losing out in the market by protecting telephony revenues, and instead a new class of Internet Service Provider will come into existence dubbed the Internet Telephony Service Provider.