100G DWDM FEC standard

[roll at Stupi.SE (Peter Lothberg)]

> From a standards perspective keep in mind that
> http://www.stupi.se/Standards/100G-long-haul4.pdf is not approved -
> but we are working hard on it. OTOH having a reference
> implementation at hand, is an accelerator that helps a lot.

There is a whole industry that do not want it to be plug and play...  

(The ones that do not make routers or switches..)

> Let me also add some color to your email as the current
> interoperability situation in WDM is quite funny. Sometimes
> transceivers of the same vendor can't talk to each other, as they
> are based on a different generation of ASICs and therefore FEC
> implementations. In other words, vendors typically have more than
> only one secret sauce they cook with, and different sauces do not
> blend well :-) .  Perhaps transport folks are already too used to
> deal with such kind of issues that no one laments anymore. On the
> other hand perhaps, the networking industry is already so used to
> Ethernet where interopera bility is a no-brainer, that it is
> difficult to imagine what it means to deal with a technology that
> prevents multi-vendor interop. 

All vendors have secret souce for 100G SD-FEC, and just the fact that
you can wire the wire the differential encoding eight ways..

That;s why we settled on a HD-FEC that can be inside the DSP-Asic or
inline after it. All to us known DSP implementations supports this
with more, less or no extra logic. And the logic is free and fully
documented. 

> To confirm your final point:
> Interoperability is on the top of the shopping lists for the
> networking industry.

Amen!


-P