1. A method of providing adaptive segmentation in a higher protocol layer interacting with a lower protocol layer, comprising the steps of: a) deploying an adaptable segmentation limit at said higher protocol layer defining a threshold of a largest Protocol Data Unit (PDU) to be submitted to said lower protocol layer; b) determining at said higher protocol layer, for each arriving Service Data Unit (SDU), if said SDU can fit into said segmentation limit or not; c) segmenting at said higher protocol layer each SDU that does not fit into said segmentation limit into PDUs which are smaller than or equal to said segmentation limit, or performing no segmentation on each SDU that does fit into said segmentation limit; and, d) submitting the resulting PDU/PDUs to said lower protocol layer; wherein said segmentation limit is adjusted on the basis of an observation of a residual loss-rate in said higher layer protocol; and, upon observing that said residual loss-rate is above a predetermined loss-rate threshold, adjusting said segmentation limit by lowering said segmentation limit by a predetermined decreasing amount; and, upon observing that the residual loss-rate is below said loss-rate threshold, adjusting said segmentation limit by increasing said segmentation limit by a predetermined increasing amount.