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In this paper, we investigate the packet transmission delay in a time varying satellite uplink. Specifically, we are interested in bounding the packet transmission delay within the terminal router for uplink traffic in a future satellite network. Previous work has provided delay bounds for wireline networks with afixed transmission rate. However, these bounds do not apply to the time-varying satellite link that we are considering here. It has been shown that the terminal router in afuture SATCOM terminal can accommodate the varying uplink RF data rate by using Ethernet pause frames. We show that by encapsulating the pause frame information into two parameters: a window size and the minimum transmission time within a window, we are able to achieve a guaranteed packet transmission delay. We also quantify the tradeoff between the packet transmission delay and the throughput on the uplink. Experiments with a commercial-ofJ-the-shelf (COTS) Juniper Mi20 router were conducted to verify the delay bound.

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In this thesis, we consider a multi-channel ad hoc network employing frequencyagile radios that utilize direct-sequence spread-spectrum signaling. Two of the key distributed protocols for this type of network control channel access and routing. The channel-access protocol is responsible for controlling access to the channels available to the terminals in the network, and the routing protocol determines how packets are forwarded among the terminals in the network. To achieve reliable and efficient network performance, these protocols should cooperate with one another and take advantage of the multiple channels available to the network.In this thesis, we investigate a number of channel-access strategies for selecting a channel as well as various channel metrics to be used with routing. For our channelaccess protocol, one channel is designated the control channel and is used to reserve access to one of the traffic channels. The channel-access protocol selects the traffic channel for a data packet transmission by examining the characteristics of the different traffic channels. New channel metrics are proposed to characterize the channels, and the metric values are used to assign a link resistance value for a link. Least-resistance routing utilizes the link resistances to calculate routes. The performance of the channel metrics for the routing protocol and the channel-access strategies are examined with a discreteevent simulation. From our investigations, we show that a jointly designed protocol that coordinates the channel-access strategies with the channel metrics results in network performance that is better than traditional channel-access and minimum-hop routing protocols.iii ACKNOWLEDGMENTS

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