Patent ID: 7751441

Claim:
A method for exchanging data packets between two service providers of a radio transmission system, the method comprising: retrieving, via a first service provider, a first data packet at a first service access point; dividing, via the first service provider, the first data packet into a first set of data segments; generating, via the first service provider, a packet data unit from a first data segment of the first set of data segments and a second data segment from the first set of data segments, wherein: the packet data unit has a first control data field including a bitmap, the first bit of the bitmap indicating whether the first data segment contains a first data segment control data field including a first length indicator, and the second bit of the bitmap indicating whether the second data segment contains a second data segment control data field including a second length indicator; and transferring, via the first service provider, the packet data unit, via a second service access point, to a second service provider.