Technique for providing a secure link in a mobile communication system

When claims a to be in a mobile communication system in the link layer protocol entities disposed on the conversion providing technology for security link. The first pair of link layer protocol entity comprises a first transmission link layer protocol entity and said first concave layer protocol entity. The second pair of link layer protocol entity comprising a second transmission link layer protocol entity and second receiving chain layer protocol entity. A technique adopted the following way is realized: First suspends of the first transmission link layer protocol entity to the data transmission of the first receiving chain layer protocol entity, while starting from the second transmission link layer protocol entity to the data transmission of the second receiving chain layer protocol entity. The data connection of the first transmission link layer protocol entity which is confirmed therefore transmit the first receiving chain layer protocol entity of the first transmission link layer protocol entity via the second transmission link layer protocol entity and second receiving chain layer protocol entity through the tunnel.