Toshiba Phone System

Are different voip systems cross compatible?

I would like to know if different voip systems are compatible with each other, specifically, Skype Tesco Internet Phone Sip Also would someone knowledgeable on the voip subject please post a concise explanation of all the different networks. Many thanks!

Public Comments

1. it depends. Voip is cross compatible with another VOIP system but not with skype for example. Peace
2. Skype and Vonage use VoiP (Voice Over Internet Protocol) Hardware for these are compatible, but their hardphones have embedded software for their particular service. I know that Tesco and BT Broadband Phone use SIP Technology (Session Initiation Protocol) , The technology is compatible, but I don't think that they can connect together. Skype doesn't use SIP, therefore its not compatible with Tesco and BT. I also have a Nokia E61 that has built in SIP compatibility via WiFi and so should be capable for BT or Tesco.
3. There's a Usenet discussion group called uk.telecom.voip where day-to-day comments on the different services takes place (I'm not currently using VoIP very heavily, but have tried out the X-lite software and use Sipgate.co.uk for incoming calls). Skype is currently incompatible with other systems, which could be seen as a disadvantage (because with hundreds of thousands of users, Skype is probably one of the most popular ways to chat with others, but like the VHS vs Betamax video recording standards, the popular might 'beat' the other, more superior system). I have seen mention of using different hardware (if you look at the www.sipgate.co.uk web site, you'll see various phones and adaptors {to let you plug an answerphone in, for example}) which is aimed at SIP users, but cannot comment on whether the Tesco deal is good value or not. As for a summary of the different networks, sorry, have not got 2 hours to search for that - there may be a VoIP site which covers this (also, whether a list is any good depends on (a) where you are, and (b) where you will be calling most, as there might be choices in UK / Europe / USA which are best depending on your calling patterns)... Having said I've not gone searching, the Wiki page at the end of this response does list a number of services, but full credit to contributors on Wikipedia for that :) To be useful a comparison website would need to get fine detail like whether the services offer only outgoing calls, and for those that allow incoming, whether they use 0845 (like Tesco?) or 0870 (costly to ring) or 056xx (not working from abroad) or a " normal " geographic number starting 01xxx or 02x xxxx (assuming you are in the UK, of course) NB there are other standards like IAX (see the Wiki page about Skype for the names of the competitors to Skype :) )