Bundling and multiplexing in packet based mobile backhaul

This paper investigates the bandwidth efficiency of packet based mobile backhaul in case of low rate, delay sensitive voice service. Evolved HSPA is a fully packet based mobile technology where the voice service is VoIP based. VoIP sources generate small packets periodically. The overhead on these packets is significant; it even exceeds the useful payload, causing efficiency problems on the mobile backhaul where bandwidth is still a scarce resource. A possible way to improve the efficiency of the voice service is to aggregate multiple voice packets into a single transport frame, a technique that reduces the relative overhead. This paper provides an overview of the available aggregation methods referred to as bundling and multiplexing. The performance of these solutions and their impact on the QoS of the voice service is investigated with simulations. Results show that if the backhaul is the bottleneck, the maximum number of VoIP connections that can be served jumps by up to 60%.