SIP Provider Deutsche Telekom, Call & Surf Connection (DE)

The Deutsche Telekom is offering the possibility to perform telephony on a SIP base to their private customers, when using their Call & Surf connections. This is not a traditional SIP trunk, but nevertheless the SwyxWare can be configured accordingly use this connection for telephony.
This can only be used when it is combined with internet access from Deutsche Telekom, it cannot be used an any other internet connection.

DNS configuration

Basically the DNS server of the respective Internet access provider should always be entered on the SwyxWare server (or router).

DNS in the VoIP environment for Telekom connections

For Telekom connections with PPPoE dial-up (xDSL), these are automatically assigned when dialing in. For CompanyConnect (CoCo)/GermanyLAN Connect IP (DCIP) as well as for Business Premium Access (BPA) these are stored on the customer letter. There must be no confusion between CoCo/DCIP and BPA DNS servers!

The DNS server for the respective product must always be used. In the worst case, incorrect configuration can lead to SIP trunks not being registered, to temporary problems (e.g. dropped calls) or to Quality of Service (QoS) not working. The customer should therefore know whether he has a CoCo, DCIP or BPA.

Important: Currently, for a reliable operation of a SwyxWare on a Call & Surf connection, at least SwyxWare2015R with a CHF has to be installed. 

Configuration

Required information:

• Access number (previously T-Online Number) or its alias, i.e. 11223344
• Personal password for the Telekom Call & Surf connection
• assigned numbers (usually threei), i.e.. 040112233, 04011223334, 040112235

These information is provided by Deutsche Telekom when the connection is created or can be accessed through the Telekom customer center.

For each single assigned number, a dedicated SIP trunk group must be created. When configuring the user data for each SIP trunk, the associated public number must be entered as User ID in format canonical with plus, i.e. +4940112233. The Access number or its alias must be extended by '@tel.t-online.de' and entered as User Name, i.e. 11223344@tel.t-online.de. In order to enable forwarding of inbound external calls to another external destination, the number of simultanous call on each trunk must at least be '2'.

After the public calling number was assigned to a user, the exclusive usage of this trunk for that specific user must be configured through the routing records of the SIP trunk.

If an external, inbound call needs to be forwarded to another external destination, it is necessary to signal the public number of the forwarding party. This has to be configured in the tab 'NUmber signaling' of the trunk properties (Use: Originator's number, if assigned to this trunk, otherwise: Number of the transferor.)

For your convenience the generated CustomProviderProfiles.config is available for download at the end of this article. Extended information about how to use this file can be found at Configuration and Adaptation of SIP Providers via Provider Profiles.