An Internet Protocol (IP) headers decompressor node, a method and an IP headers manager in an IP network for fast IP headers compression initialization is thereby provided. The invention teaches how to exchange IP packets between at least two nodes of the IP network for establishment of a session therebetween, to initialize, at a first one of the at least two nodes, a static portion of a decompression context prior to completion of the establishment of the session and to uncompress application related IP packets exchanged with a second of the at least two nodes. In an optional embodiment of the present invention, it is further taught how exchanging IP packets between at least two nodes of the IP network may further comprise extracting information from the IP packets at a first one of the at least two nodes of the IP network.