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Re: Does Ten-Gigabit Ethernet need fault tolerance? (POP review advice)

Those people reading the RTFC Principles of Operation may wish to keep a
few points in mind:

RTFC assumes smart NICs and dumb hubs.  However, for 10GbE we probably
would want dumber NICs and smarter hubs, both to allow a single NIC design
to be used for both FT and non-FT systems, and to allow the hub to assign
NodeIDs, rather than having to depend on humans to manually set these in
strictly increasing numerical order on the NIC cards.  Letting users out of
handling such a critical step is probably essential.  So, don't feel that
the partitioning set forth in the RTFC Principles of Operation is in any
way required; I would expect GbE to repartition the rostering algorithm
between NICs and hubs.

The NICs could be designed such that up to four standard-issue NIC cards
could be installed side-by-side in a single PCI bus, strapped to
communicate with one another via the PCI bus they share, together
implementing a RTFC quad node.  Or, one could implement dual-ring NIC
cards, with two dual cards side by side to implement a quad redundant
system.  My guess would be that most commercial users will find that dual
suffices, while there are military applications for both dual and quad
redundant systems.  Basically, dual redundant suffices for ordinary fault
tolerance, but quad redundant is often needed for battle damage tolerance.


The basic technical document, the RTFC Principles of Operation, is on the
GbE website as:

The first document is the text, and the second contains the drawings.