The database that describes the overlay domain topology is stored in a distributed database.
Every Network Monitoring Element (the theodolite in the previous terminology) hosts a proxy of such abstract entity.
Such component keeps updated a local image of the database. Updates are propagated using an epidemic, peer-to-peer protocol.
The footprint of such protocol is kept under control by adaptively changing the number of tokens in the system, using a fully distributed feedback algorithm.
The simulation of such protocol in a system of 1000 NME gave encouraging results:
update frequency 1/5 1/secs overall traffic 5 MB/sec update latency 40 secs
with a setup which is appropriate for a classical packet switching environment.
The simulation proved that the algorithm is self-stabilizing under
severe stress (for instance, doubling instantaneously the number of
NME
next: Layout of the NME
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