Hello, the variables attached to a transaction are the avps and xavps, but at this moment you cannot add one if the transaction is not active (under processing by config interpreter) at that moment. It would be possible if you want to write some C code: search the transaction by its id, then you can add avp/xavp as you can access the lists inside the transaction structure. Without C code, a solution for now will be to store the value in a hash table using a key like "transactionid:varname", then when the processing of the transaction is resumed, then you can check in hash table and fetch the value from there if exists. The transaction id is unique for a lot more than the lifetime of the transaction, if you set auto expire for the htable for a value that matches the transaction lifetime (see tm parameters), then all should be safe. Cheers, Daniel On 25.12.17 18:00, voipspace voipspace wrote: -- Daniel-Constantin Mierla www.twitter.com/miconda -- www.linkedin.com/in/miconda Kamailio Advanced Training - www.asipto.com Kamailio World Conference - May 14-16, 2018 - www.kamailioworld.com