RE: PMD Compromise
Jay Hoge wrote:
> Upon reflection, I agree with you on the 1.3u vs.
> 1.55u smf issue. If people want to go truly long
> haul in native Ethernet, there needs are
> outside the scope of this standard.
No, I think that would be a mistake! This standard can't afford to
ignore a sizeable market need - how useful is a standard that fails
to specify a version many people want? Please allow me to argue in
favor of keeping 1550 nm link on the table.
Ethernet backbone over dark fiber is appealing. It is a fast and
affordable alternative to SONET, enabling cost-effective high
bandwidth connectivity to data centers and Internet. Market is
changing; so should change the scope of a new standard. Metro links
are increasingly in demand, and we can't be sure that >40 kms will
be an insignificant piece of that market. If anything, we are
getting the opposite message from the market - sales of 80-km GBICs
are increasing at a rapid rate. We can't afford to ignore these
trends when drafting a new standard.
The 1550 nm PMD will be expensive by LAN standards, but it will be a
bargain compared to SONET monthly rates. As volumes build up, prices
will drop further.
In the near future, when we consider 40G operation, a 4:1 WDM of 10G
Serial links will be one of the major options. Compatibility with
1550 nm WDM devices and amplifiers will be required then. I know we
are not obliged to take this future event into account, but why not
think about it?
By refusing to standardize a significant market need, we will be
depriving the market of some key lubricants - interoperability,
competition and lower cost. The market will prevail despite us, but
magazine articles for years to come will keep reminding us of what a
poor decision we made.