An analysis of the heterogeneity and IP packet reordering over multiple wireless networks

Abstract

Abstract-With the increasing deployment of wireless technologies, such as WLAN, HSDPA, and WiMAX, it is often the case that simultaneous coverage of several access networks is available to a single user device. In addition, devices are also often equipped with multiple network interfaces. Thus, if we can exploit all available network interfaces at the same time, we can obtain advantages like the aggregation of bandwidth and increased fault tolerance. However, the heterogeneity and dynamics of the links also introduce challenges. Due to different link delays, sending packets of the same flow over multiple heterogeneous paths causes the reordering of packets.In this paper, we quantify the impact of network heterogeneity and the use of multiple links on IP packet reordering. We show with practical measurements, according to commonly used metrics, that packet reordering over multiple links exceeds the reordering caused by common connections in high-speed, widearea networks. We also demonstrate that heterogeneity and reordering exceed the assumptions presented in related work.By using sufficiently large buffers, packet reordering can be avoided. However, for devices with high resource constraints, the workload of using large buffers is expensive. Sender-side solutions of dividing and scheduling a packet sequence over multiple links can reduce the buffer requirements at the receiver. Initial experiments with a static scheduler, that has knowledge of average link delay and throughput estimates, show that packet reordering can be reduced by only 38 % due to the dynamic heterogeneity of the two links.

Multipath aggregation of heterogeneous access networks

“…In this chapter, we also propose NAMA, a network-layer prototype capable of aggregating multiple paths while keeping packet reordering at a minimum. The content of this chapter was published partly in [45] and [92].…”

“…Last but not least, combining our work with energy-efficient ESP-based forwarding, as documented in RFC 5984 [117], should be considered. [92].…”

OSIA: Out-of-order Scheduling for In-order Arriving in concurrent multi-path transfer

“…Furthermore, a sub-flow level (flowlet) scheduling has been proposed (Kandula et al, 2007) to tackle this problem with granularity, but it is not fine enough to quickly assign the desired load share to each path. In contrast, Kaspar et al (2009) address and quantify the impact of packet reordering due to the multi-path heterogeneity when performing CMT, but their solution does not make full use of the network resources and cannot be suitable to the dynamic mobile networks.…”

Mobile video streaming using location-based network prediction and transparent handover

“…However, to the best of our knowledge, no other system integrates everything into one solution and presents a running prototype with real-world experiments, i.e., they do not experience all the possible real-world complications [10,17]. Our solution predicts the availability of several networks and their bandwidths at the different locations along the path, and then it plans and adapts video quality to available bandwidth for a mobile device.…”