摘要 |
In a method of improved session negotiation between first and second clients in a cellular telecommunication system, the two clients negotiating S10 and agreeing upon a first codec type for a session. The first and second clients then initiating the session and exchanging S20 media data frames according to the first codec type. Subsequently, during the initiated session, at least one of the first and second clients providing S30 an indication for a second codec type in at least one subsequent media data frame. Finally, upon receiving and recognizing said indication, the other of said first and second clients switching S40 to the indicated second codec type in a next media data frame, thereby enabling the first and second clients to exchange subsequent media frames utilizing the second codec type. |