How can I implement the sip protocol in my browser (IE10, Firefox,Chrome), so that I can write in the address bar sip:user@domain.com
or
When I click on an icon (f.e. a telephone) then it should open a softphone (SJPhone is the one I’ve used)
(I manage to do it many years ago for Firefox, but I’ve forgotten it and can’t find it again. ) 
Take a look on SIP Javascript APIs like SIPML5 & JsSIP.
[quote=“henkoegema”]How can I implement the sip protocol in my browser (IE10, Firefox,Chrome), so that I can write in the address bar sip:user@domain.com
or
When I click on an icon (f.e. a telephone) then it should open a softphone (SJPhone is the one I’ve used)
(I manage to do it many years ago for Firefox, but I’ve forgotten it and can’t find it again. ) [/quote]
I found how I did it in Firefox: blog.n3tg33kz.com/2010/12/adding … o-firefox/ 
But I haven’t found it yet in IE and Chrome. 
You can use WebRTC which is a relatively new standard…
en.wikipedia.org/wiki/WebRTC
Or use an java (or any other language) embedable softphone… for example Mizu
mizu-voip.com/Products/WebPhone.aspx
[quote=“hector_alvarez”]You can use WebRTC which is a relatively new standard…
en.wikipedia.org/wiki/WebRTC
Or use an java (or any other language) embedable softphone… for example Mizu
mizu-voip.com/Products/WebPhone.aspx[/quote]
Thanks Hector. I’ll have a look at that. 