[802.3BA] WAN PHY and DWDM interaction (was Re: [802.3BA] Longer OM3 Reach Objective)
On Tue, 25 Mar 2008, Paul Kolesar wrote:
> 10GBASE- we have the original four, some multiplied by two for LAN (R) and
> WAN (W): S, L, E, LX4. The WAN interfaces have not found much of a market
> and are probably dying or dead.
I have to object here. WAN PHY lives on in equipment that have framers
that do both modes. It's extremely useful in a DWDM environment and I know
numerous people that will happily take the higher CAPEX of linecards that
support this, plus the slightly lower bit speed, to get the AIS/RAI
signalling from the DWDM system, because it saves on OPEX.
WAN PHY was killed by lack of framers in the beginning, plus the fact that
I believe that numerous vendors saw WAN PHY as competition for their POS
interfaces and therefore chose to price it very high (hope this is an ok
place to mention price).
The fact that most people thought WAN PHY was an optic variant doesn't
help either. The naming confusion lives on in the fact that the same XFP
today (10 km SM) will have two names depending on if you use it in a
OC192/STM64 POS role or 10GBASE-LR/LW role (SR and LR/LW respectively).
Very confusing. Let's not make that mistake again.
I still til this day think that WANPHY was a great idea and would have
been adopted much more in the ISP environment if vendors would have dared
to make the investment needed to get it out the door. Instead if was
hindered by the aftermath of the bubble, right in the middle of a
recession where investment was low and a lot of companies were in pure
survival mode.
I have to chime in with the guys from Huawei that we need to have basic
remote fault signalling in 100GE at the hardware layer, otherwise it won't
take off in the WAN. Make it optional if you want to, then we as customers
can put it into our RFQs when we want to buy equipment.
--
Mikael Abrahamsson email: swmike@swm.pp.se