Experimental Evaluation of PDU Concatenation in ULE with IP Telephony

Efficient encapsulation of IP and other network packets is an important issue for wireless links. The Unidirectional Lightweight Encapsulation has been designed to be efficient, yet flexible in providing means to add new header extensions for developing requirements. One of the recently proposed extensions allows for wrapping several network packets into one SubNetwork Data Unit, the PDU-Concat mode. In this paper we give some first results on both the efficiency of this mode, but also critically analyze impacts of the concatenation on real-time audio traffic for IP telephony. For the tests a combination of a laboratory set-up with a DVB-C chain for the PDU-Concat processing and the Astra2connect network for the real satellite networking part has been utilized.