Technique for controlling establishment of a tandem-free transcoder operation

A method of controlling establishment of a tandem free operation (TFO) for transfer of TFO frames including content frames between a first and a second transcoder unit without transcoding of the content frames, the method comprising the following steps:

• receiving, in context with a TFO request, information about a remotely used codec associated with a remote transcoder unit;
• determining, in response to the TFO request, if the remotely used codec meets a codec compatibility condition;
• transmitting, in case the remotely used codec does not meet the codec compatibility condition, a first transparent mode message indicating to in-path equipment a transparent mode for subsequent transparent TFO negotiation;
• and
• transmitting, in the transparent mode, a TFO configuration frame indicating a local TFO codec list.

A transcoder unit adapted for controlling establishment of a tandem free operation (TFO) for transfer of TFO frames including content frames between a first and a second transcoder unit without transcoding of the content frames, the transcoder unit comprising:

• a reception component adapted for receiving in context with a TFO request information about a remotely used codec associated with a remote transcoder unit;
• a determination component adapted for determining, in response to the TFO request, if the remotely used codec meets a codec compatibility condition;
• a message transmission component adapted for transmitting, in case the remotely used codec does not meet the codec compatibility condition, a first transparent mode message indicating to in-path equipment a transparent mode for subsequent transparent TFO negotiation;
• and
• a frame transmission component adapted for transmitting, in the transparent mode, a TFO configuration frame indicating a local TFO codec list.