Deutsche Telekom offers its business customers a SIP trunk with user authentication, i.e. you receive information on UserID, UserName and UserPassword, although the names may vary, or you only receive the user name and password. In this case the UserID is identical with the UserName.
Important: The CompanyFlex SIP Trunk of Deutsche Telekom was first tested and released with a SwyxWare 12.00.0.0. Operation with an earlier SwyxWare version is not possible.
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.
DNS in the VoIP environment with third-party access
If the customer uses a third-party access (e.g. Vodafone as carrier line) the DNS servers of the provider should also be entered. If these do not support eDNS and ECS, the address 126.96.36.199 of the third-party provider Quad9 can be used. Internet access via Telekom LTE is also considered third-party access (voice products via LTE are currently not released).
Under no circumstances should Telekom DNS servers be used for third-party access.
The SIP trunk of Deutsche Telekom can be used without restrictions from SwyxWare 12.00.0.0
The CompanyFlex SIP Trunk from Deutsche Telekom is not suitable for operation in data centers.
Support for data center operations will be available from Q4/2020 at the earliest.
When creating the SIP trunk group, 'Telekom CompanyFlex TCP (DE)' must be selected as the profile. If encryption is desired, 'Telekom CompanyFlex TLS (DE)' must be selected as profile. For this it is necessary to import the Telekom root certificate into the Windows Certificate Store of the SwyxWare server. For more information see the download link at the end of this article.
- Registration number
- Telefony Password for the CompanyFlex SIP Trunk
- The assigned number blocks and if applicable MSN numbers
This information was provided by Telekom when the connection was set up, or can be retrieved via the customer center.
When entering the user data for a created SIP trunk, the registration phone number must be entered as User ID and User Name.
In the codec dialog for FAX transmission via T.38 the two options "Remove T.38 codec from initial invite" and "Prohibit T.38 reinvite by sender" must be activated.
A detailed configuration guide is available for download at the end of the article.
Configuration of CompFlex SIPTrunk
If external calls are immediately forwarded to another external destination, especially to the mobile network, call termination may occur. Other situations leading to call termination are also possible. The call terminations are initiated by the CompanyFlex platform if, in the standard case, a corresponding signal is not given within three seconds.
The timer for this call abort can be increased in the Business Service Portal.
Instructions for setting this timer are available for download at the end of this article.
- Incoming/outgoing national calls
- Incoming/outgoing international calls
- Correct Calling Line Identification (CLI) on national and international calls
- CLIP No Screening
- Holding and retrieving calls
- Toggling between two calls
- Call transfer
- Call forwarding
- Incoming/outgoing DTMF signalling in accordance with via RFC2833
- FAX transmission via T.38
09/12/2019 with SwyxWare 12.00.0.0
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