[Css-csts] FCLTU earliest-radiation-time = latest-radiation-time

[John Pietras]

Wolfgang,

In the F-CLTU Blue Book (B-3), paragraph 3.6.2.7.5 states "If
latest-radiation-time equals earliest-radiation-time, radiation shall
occur at this time."  A question has come up involving the case where,
for some reason, the CLTU cannot be radiated at that exact moment
(millisecond or picosecond, depending on the selected resolution of the
radiation time parameters), but could be radiated at some (arbitrarily
small) time afterward? 

 

One school of thought is that the CLTU should be discarded because it
exceeds the LRT.

 

A different school of thought is that the CLTU could (should?) be
retained and radiated as soon as possible after LRT, to allow some
"leniency" for miscalculated link rates, inserted idle sequences, etc.
The counter argument is that if the User wants to have such leniency
applied, then the CLTU-TRANSFER-DATA invocation should either have an
LRT that is actually later than the ERT, or have a null LRT. That is.,
LRT = ERT should only be used when the user has a specific requirement
that the CLTU *must* be radiated at that exact moment, and to do so at
some other time (even a few milliseconds later) would render the CLTU
non-effective or possibly even counter-productive .

 

I happen to fall into the "discard if it can't be radiated at the exact
moment" camp. But if any existing FCLTU implementations do otherwise, or
if a valid argument can be made to do otherwise, I'd very much like to
hear about them.

 

Thanks (as always) for your help.

 

Best regards,

John

 

John Pietras

GST, Inc.

7855 Walker Drive, Suite 200

Greenbelt, MD 20770

240-542-1155

 

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