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RE: Renaming the WAN PHY


Having been down a similar path with POS (Packet-over-SONET) I don't see how
you can have a SONET compatible phy that isn't SONET compliant.  As I
understood it the reason for having a SONET framed interface in the first place
was to be compatible with the installed SONET based transport and DWDM
networks. To meet this requirement I think the interface has to be SONET
compliant, in the same way that POS interfaces have to be compliant with all
the appropriate Bellcore and ITU SONET/SDH standards.

I think it would be very confusing to  to have an interface that 'looks and
feels' like SONET but in fact isn't. If that is really the intent then I think
it needs to be clearly distinguished from a 'real' SONET interface.

Gary Nicholl .............

At 04:56 PM 3/24/00 , David Martin wrote: 

> How about "SONET-compatible PHY". While I could agree to drop the "WAN" 
> portion of the name, we still need to be clear that our proposal is not a 
> SONET-compliant PHY. There is a significant cost/feature difference. To
> reiterate, 
> the "SONET-compatible PHY" has the following key differences:  
>    * minimal OH processing (i.e. only 4 OAM bytes, not SONET's
>    36-A1/2-H1/4=30)  
>    * wider clock tolerance (i.e. the usual +/-100ppm, not SONET's +/-4.6ppm)  
>    * higher jitter tolerance (i.e. >0.15UIpp of SONET, exact value still TBD) 
>    * low cost optics (i.e. for <40km, not the 80/120km of SONET OC-192) 
> All of which will "bring the cost down out of the stratosphere" to paraphrase
> a 
> committee member and in line with the 3x1GE target. 
> ...Dave 
> David W. Martin 
> Nortel Networks 
> +1 613 765-2901   
> +1 613 763-2388 (fax) 
> <mailto:dwmartin@xxxxxxxxxxxxxxxxxx>dwmartin@xxxxxxxxxxxxxxxxxx 
> ========================  
> -----Original Message-----  From:   Bruce Tolley [SMTP:btolley@xxxxxxxxx] 
> Sent:   Friday, March 24, 2000 2:50 PM  To:     stds-802-3-hssg@xxxxxxxx 
> Subject:        Renaming the WAN PHY 
> Colleagues: 
> To follow up on the suggestion made by Jonathan during the New Mexico 
> plenary, may I be so bold as to suggest that we change the name of the "WAN
> PHY" to something very simple like PHY with SONET framer. 
> We need to get the word WAN out of the name of the PHY 
> o Most common folk outside the esteemed IEEE process think long distance  when
> they think WAN and on the basis of Paul Bottorf of Nortel,'s presentations
> the initial application of the WAN PHY would be for short links between
> collocated equipment often in the same room. 
> 2) There are ways to build MANs/WANs that do not require SONET. For 10GbE 
> some of these MANs/WANs will use the LAN PHY and a 1550 PMD over dark fiber
> or dark wavelengths. The proof point for this is the 1000s of long distance
> 1310 nm 1550 nm 1000BASE-X GBICs  that are being deployed today over dark
> fiber.  The WAN PHY as stated in the goal does not address the total possible
> 10GBE WAN market and confuses people.. This makes it a bad name in my opinion
> I do not think we necessarily need a motion to change the objective, but I 
> think we need to choose our words carefully when we name the PHY that the
> objective signifies. 
> Bruce  Cisco Systems