Are special services, such as Caller-ID, 3-way calling, voicemail, etc. supported ?
VoIP Service providers may choose to provide some or all of the additional services. Note that if you have a Vigor 2100V or 2500V model, the issue is more involved, because these units connect to PSTN provider as well as a VoIP Provider. Please see the Vigor 2100V and 2500V FAQ for further details.