A network-layer proxy for bandwidth aggregation and reduction of IP packet reordering

Abstract

Abstract-With today's widespread deployment of wireless technologies, it is often the case that a single communication device can select from a variety of access networks. At the same time, there is an ongoing trend towards integration of multiple network interfaces into end-hosts, such as cell phones with HSDPA, Bluetooth and WLAN. By using multiple Internet connections concurrently, network applications can benefit from aggregated bandwidth and increased fault tolerance. However, the heterogeneity of wireless environments introduce challenges with respect to implementation, deployment, and protocol compatibility. Variable link characteristics cause reordering when sending IP packets of the same flow over multiple paths. This paper introduces a multilink proxy that is able to transparently stripe traffic destined for multihomed clients. Operating on the network layer, the proxy uses path monitoring statistics to adapt to changes in throughput and latency. Experimental results obtained from a proof-of-concept implementation verify that our approach is able to fully aggregate the throughput of heterogeneous downlink streams, even if the path characteristics change over time. In addition, our novel method of equalizing delays by buffering packets on the proxy significantly reduces IP packet reordering and the buffer requirements of clients.

Multipath Bandwidth Scavenging in the Internet of Things

“…Heterogeneous path delays and loss characteristics may trigger timeouts and retransmissions, as well as head-of-line blocking at receiver buffers, forcing larger and longer buffering to be done [2][3][4]. A better alternative would be to partition application flows into subflows and enforce per-subflow congestion control and reliability mechanisms that adapt and respond to per-subflow path congestion and loss events [5].…”

“…Maintaining TCPlike flow semantics within individual subflows also yields better compatibility with stateful middleboxes [6]. These have been the general strategies taken by the Internet community with Multipath TCP (MPTCP) which is envisioned to provide TCP the capability to 2 …”

“…DBAS' ability to deal with stateful middleboxes, as well as the ensuing fairness of its subflows is however not known. Alternatively, instead of placing the functionality within the endpoint itself, dedicated proxy middleboxes may be deployed within the network in order to do aggregation, delay equalization and packet scheduling [2,3]. This seems to be more feasible to do within the fixed infrastructure, and represents additional cost and management overhead for providers.…”

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].…”

“…Unless otherwise stated, we use our send vector approach [45] for enabling both static and dynamic packet striping. The send vector contains a simple sequence of integer numbers that identify forwarding destinations, such as different paths, client interfaces, or IP addresses.…”