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Virtual Network Configuration Overview

The Virtual Network Configuration (VNC) algorithm can be explained by an example. A remote node's direction, velocity, bandwidth used, number of connections, past history and other factors can be used to approximate a new configuration sometime into the future. All actual configuration processes can begin to work ahead in time to where the remote node is expected to be at some point in the future. If the prediction is incorrect, but not far off, only some processing will have to be rolled back in time. For example, the beamsteering process results may have to be adjusted, but the topology and many higher level requirements will still be correct. Working ahead and rolling back to adjust for error with reality is an on-going process, which depends on the tradeoff between allowable risk and amount of processing time allowed into the future. As a specific example, consider the effects of hand-off on TCP performance as described in [12]. In this work, throughputs were measured for hand-off under various conditions and determined to degrade badly.



Steve Bush
Tue Nov 12 11:48:31 CST 1996