Circuit service in deflection networks
F. Borgonovo, Luigi Fratta, Federico Tonelli · 1991
The capability of the deflection network to provide circuit service, i.e., virtual circuit service with guaranteed bandwidth, is investigated. Such a capability is achieved by modifying the datagram access algorithm and by introducing additional information in the packet header which allows prioritized access via token requests. This mechanism guarantees the needed resources to the already established connections. A second mechanism, which is superimposed on the previous one, is used to measure the resources available and to assign them upon request. The whole mechanism is completely distributed and very robust, since it is based on measures that reflect the real status of the network. A performance analysis is carried out by simulation. In particular, the capability is shown to guarantee the bandwidth to each connection, and the degradation in the network's maximum throughput due to the token mechanism is investigated. Some modifications to improve the circuit capacity are introduced and their effectiveness is evaluated.>