VCXO and XO for 64b66b
All,
For the first generation 64b66b prototypes we're most likely going to
use existing SONET mux/demux chipsets. Thus the CMU is a times
16 or times 64.
This means that the reference clocks most be 10.3125GHz/64 =
161.1328125MHz (or 644.53125MHz).
These are non-standard frequencies for most XO and VCXO
manufacturers, and the lead time is in the 3 months range. Thus, if
we don't want the 64b66b prototypes to be delayed 3 months due to
lack of oscillators, someone (e.g. a group of module and systems
vendors) should get the oscillator guys started.
In a future mux/demux chipset customized for 64b/66b the CMU
could be times 66 or times 132. Thus, then you will need 156.25MHz
or 78.125MHz XO's and VCXO's. These are also non-standard
frequencies. But then again, you might not want this when you have
already paid for your custom 161.13...MHz oscillators.
This is a very real problem for the standard effort. We need these to
demonstrate solution, and we have a very tight schedule.
So, is anyone willing to pay NRE to an oscillator manufacturer to get
this started, or should we as a group invite some oscillator
manufactorers to join the IEEE P802.3ae, and hope they will be
tempted by the potential profits?
Henning Lysdal
GIGA A/S
Mileparken 22, DK-2740 Skovlunde, Denmark
Tel: +45 7010 1062, Fax: +45 7010 1063
Direct: +45 44546 154
e-mail: hl@xxxxxxx, http://www.giga.dk