RE: [RPRWG] RPR over wireless links
Mike Takefman wrote:
> However, the design of the MAC was assuming
> fiber media, which had a very low bit error rate. I am
> aware that SONET radio links do exist and often include
> FEC coding schemes to decrease the error performance
> of the links.
Actually, as long as SONET/SDH is used, RPR does not really
care or need to be aware of the medium. Since, SONET has error
indication at the section, line and path. The SONET PHY
can indicate a Signal Fail (assuming the same criteria it uses
for SONET APS) to the RPR MAC layer. The RPR MAC
can take appropriate action as per the current draft.
If it turns that the RPR wireless spans are seeing more errors
than FEC could be used. My only concern with is that FCE
changes the end to end to delay assumptions based on interleaver
depths chosen to correct various size of burst errors.
However, as long as these delays are well within bounds, fairness
or protection should work OK.
My take is that the current draft is good for Wireless links at
155Mb/s and above.