This is a bit of story about the struggles with my ISP first, and then a poll about your situation.
I live in Germany and get my internet at home via Vodafone (the sole cable internet provider here). Included in my internet plan is a cable modem and router combo unit, the router functionality of which is not of interest to me since I am happily using pfSense at home. Therefore, I chose to enable the “bridge mode”, which disables essentially all functions of the unit and simply gives me a DHCP configured Ethernet connection out of the LAN 1 port that I can connect to the WAN port of my router. So far so good, internet works as expected.
Now for the interesting part: Whether you have bridge mode enabled or not, you are restricted to using the analogue telephone ports on the modem/router unit (with the addition that in bridge mode, you can even only use one of them). Turns out when you are using cable internet, your telephone works via “Voice over Cable”, which differs from VoIP and does not use SIP. In Vodafone’s case, modems provided by them are automatically configured by means of line identification, so your modem automatically sets up your phone number.
However, since German legislation banned compulsory routers in 2016, you do have the option to use your own cable modem instead of the provided one. In that case, Voice over Cable will be disabled and you will get SIP credentials from Vodafone.
As countless posts in their forums and a call to their hotline confirm, Vodafone apparently refuses to disable Voice over Cable and give you SIP credentials if you are using the modem supplied by them, so you can’t use your own PBX, VoIP phone or softphone. This is something that frustrates me and I can’t think of why they would impose these artificial restrictions (they won’t tell).
Now what I would like to know from you:
Is that something you experience too or does your cable provider happily hand out SIP credentials?
- I am restricted to my ISP’s modem’s telephone capabilities
- My cable ISP provides SIP credentials for me to use with any phone / PBX