SIP Provider COLT (kb5077)

The information in this article applies to:

  • SwyxWare 11

[ Summary | Information | Links ]


Information und configuration hints for SIP provider COLT.


General information

The COLT SIP Trunking Solution was first tested an released with SwyxWare

COLT offers a static SIP trunk, i.e. the public IP address of the SwyxWare Server is used for authentication. You therefore need a static, public IP address from your ISP via which the SIP proxy of COLT communicates with SwyxWare.

  • With a direct connection to the network of COLT, the SIP messages of the proxy must be sent to port 65002 of the SwyxWare Server. The network infrastructure has to be adopted accordingly.
  • When using a gateway with an Internet connection with static IP address, a port forwarding rule from public port 5060 to port 65002 of SwyxServer has to be configured on the gateway.


During creation of the SIP trunkgroup, profile 'COLT SIP Trunking' has to be selected.  If the profile is not included in the corresponding list, you can download the required CustomProviderProfiles.config for SwyxWare at the end of this article. For more information about using this file, see  Configuration and Adaptation of SIP Providers via Provider Profiles (kb3436).

COLT is operating with individual proxies per customer. Therefore it is not possible to preconfigure the Proxy Server in the "SIP" tab of the Trunkgroup Properties dialog. In field of Proxy Server, please enter the server name or IP address provided by COLT.

In case that the SwyxWare server is running with a private IP address and the static, public IP address is provided by NAT gateway, it is necessary to configure a STUN server in the properties of the SIP trunk group, in the 'SIP' tab. A list of public STUN servers can e.g. be found at should also be noted that the network environment (NAT, firewall) has allow communication with the standard STUN port 3478.
COLT offers different kinds of connection types. In some products it is possible to announce the private ip address of the SwyxWare machine on the order form of the SIP trunk. In such a case the usage of STUN is not necessary. If you have any questions regarding your kind of connection type and the respective configuration, please contact COLT directly.

Important: During creation of the actual SIP trunk, codecs G.722 and G.711u must be deselected in the codec dialog. This can also be configured after creation of the SIP Trunk.

Tested Features

  • 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
  • Toggeling between two calls
  • Call transfer
  • Callforwarding
  • Conferencing
  • Mutually supported codecs:
    • G.711A
    • T.38 for FAX transmission
  • Incoming/outgoing DTMF signaling in accordance with via RFC2833
  • Fax transmission via T.38


  • TLS trunk with client certificate not yet supported

Test date:
26/01/2018 with SwyxWare


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