QOS considerations for future military satcom networks with link layer dynamic resource allocation

Abstract

SUMMARYTo efficiently utilize limited RF resources, future military packet-switched satellite networks will dynamically allocate resources on the uplink and downlink. Designing the resource allocation algorithms to maximize link layer efficiency is insufficient. The resource allocation algorithms must work cooperatively with the network layer and transport layer to optimize network layer performance and provide quality of service (QoS) to applications and users. Several mechanisms for facilitating this required cooperation between the layers are presented. The individual roles and actions of the layers as well as their interaction are defined. QoS schedulers that continue to provide service differentiation in the presence of link variations are illustrated. Downlink scheduling architectures that provide terminal QoS guarantees are demonstrated. Finally, the interaction between TCP and the dynamic resource allocation algorithms is investigated, leading to suggested modifications of either the resource allocation algorithms, the TCP protocol, or both.

Guidelines for sizing traffic queues in terminals of future protected satcom systems

“…However, to accommodate the timevarying rate of the RF link, a flow control mechanism between the COTS router and modem is required to prevent packet loss due to rate mismatch. In previous work [4], Ethernet pause frames are shown to be a viable flow control mechanism to moderate the router egress interface rate One way in which functionality of a terminal can be partitioned and implemented is presented in Figure 1. This terminal consists of terminal command software, the terminal modem or digital hardware core, and a COTS router.…”

“…DRA can potentially change the rate of the RF channel on epoch timescales, where an epoch is on the order of a second. The characteristics of the DRA algorithm used in this paper are as described in [4].…”