A cluster of 13 telecoms and internet companies with an interest ininternet telephony have formed the Internet Telephony ServiceProviders Association (ITSPA)

The UK-based association will seek to establish new standards,
including secure IP transmission systems, to allow customers to route a variety of calls wholly or partially across the internet.
 
ITSPA claims that there are six million users of internet telephony
services, mostly in the US and Japan, and it expects to see large
numbers of users in the UK very shortly.