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Orderwire Performance Emulation

The emulation of the orderwire systems satisfies several goals. It allows tests of configurations that are beyond the scope of the prototype RDRN hardware. Specifically, it verifies the correct operation of the RDRN Network Control Protocol in a wide variety of situations. The emulation helps to verify the correctness of the analytical results obtained above. As an additional benefit, much of the actual orderwire code was used by the Maisie [19] emulation allowing further validation of that code. The Edge Switch (ES) and Remote Node (RN) are modeled as a collection of Maisie entities. This is an emulation rather than a simulation because the Maisie code is linked with the working orderwire code and also with the topology algorithm. There is an entity for each major component of the RDRN system including the GPS receiver, packet radio, inter ES links, RN to ES links and the Master, ES, and RN network configuration processors, as well as other miscellaneous entities. The input parameters to the emulation are shown in Tables 3, 4, 5.



Table 3:   NCP Emulation Mobility Input Parameters.



Table 4:   NCP Emulation Time Input Parameters.



Table 5:   NCP Emulation Beam Input Parameters.

The RN VC setup process for connections over the inter ES antenna beams is assumed to be Poisson. This represents ATM VC usage over the physical link. The RN will maintain a constant speed and direction until a hand-off occurs, then a new speed and direction are generated from a uniform distribution. This simplifies the analytical computation. Note that NCP packet transfer times as measured in Table 2 are used here.

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