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Re: [RPRWG] Phy Layer question



Devendra, it may be a bit early for discussions on specific PHY layers (although I would expect the July meeting to include such sessions).  It would be my hope that such sessions are scheduled in as aspiring section editors make presentations of their first drafts showing the section structure and some of the early detail.
 
Best regards,
 
Robert D. Love
Chair, Resilient Packet Ring Alliance
President, LAN Connect Consultants
7105 Leveret Circle     Raleigh, NC 27615
Phone: 919 848-6773       Mobile: 919 810-7816
email: rdlove@xxxxxxxx          Fax: 720 222-0900
----- Original Message -----
Sent: Friday, April 20, 2001 11:31 AM
Subject: RE: [RPRWG] Phy Layer question

Robert,
 
Although I mentioned the informative section for example PHYs, I like your suggestion of specifying
a few PHY interfaces through normative sections. Is there an item on agenda for discussing various
such PHYs ?
 

Regards,

Devendra Tripathi
VidyaWeb, Inc
90 Great Oaks Blvd #206
San Jose, Ca 95119
Tel: (408)226-6800,
Direct: (408)363-2375
Fax: (408)226-6862

-----Original Message-----
From: RDLove [mailto:rdlove@xxxxxxxxx]
Sent: Friday, April 20, 2001 7:57 AM
To: Devendra Tripathi; Karighattam, Vasan; stds-802-17@xxxxxxxx
Subject: Re: [RPRWG] Phy Layer question

Devendra, I have a very different view of what "PHY agnostic means.
 
I believe that we must design the MAC to be able to work without depending on any specific PHY implementation. 
 
However, as we write the standard, we must precisely specify how we will operate with whichever PHY layers we support with that release of the standard.  There will be normative sections (that is to say, sections that specify what SHALL be done) that describe how we will work with any particular PHY.  I expect that we will need one editor for each PHY that the standard will support, and these sections will contain significant detail.
 
As an example, look at the 100 Mbit/s Token Ring standard which uses the Ethernet signaling layer.
 
Best regards,
 
Robert D. Love
Chair, Resilient Packet Ring Alliance
President, LAN Connect Consultants
7105 Leveret Circle     Raleigh, NC 27615
Phone: 919 848-6773       Mobile: 919 810-7816
email: rdlove@xxxxxxxx          Fax: 720 222-0900
----- Original Message -----
Sent: Thursday, April 19, 2001 3:22 PM
Subject: RE: [RPRWG] Phy Layer question

My understanding of saying PHY agnostic is that we specify the interface in logical way (request,
indication) with may be one example (likely Ethernet) PHY as informative annex.
 

Regards,

Devendra Tripathi
VidyaWeb, Inc
90 Great Oaks Blvd #206
San Jose, Ca 95119
Tel: (408)226-6800,
Direct: (408)363-2375
Fax: (408)226-6862

-----Original Message-----
From: owner-stds-802-17@xxxxxxxx [mailto:owner-stds-802-17@xxxxxxxx]On Behalf Of Karighattam, Vasan
Sent: Wednesday, April 18, 2001 10:59 AM
To: stds-802-17@xxxxxxxx
Subject: [RPRWG] Phy Layer question

I am new to the group.  I have been reading  up the presentations. I have a simple question.
We are saying .17 will be layer 1 agnostic.  However, (if sonet is the phy used) sonet is aware of the ring structure - for APS, etc.
Will the .17 specify how a sonet framer should be defeatured to work with a RPR MAC?
 
Thanks,
Vasan Karighattam
Architect
Intel Corporation
9750 Goethe Road
Sacramento, CA 95827
(916)855-5177  x4907
 
-----Original Message-----
From: Khaled Amer [mailto:khaledamer@xxxxxxx]
Sent: Tuesday, April 17, 2001 4:15 PM
To: Harmen van As
Cc: stds-802-17@xxxxxxxx
Subject: Re: [RPRWG] Definition of terms - First set

Sounds great. The definition sounds more clear too.
The only minor tweak that I would suggest is to replace the word node with flows or conversations in the end of the definition which would make it:
 
Bottleneck-link fairness: Fairness based on a mechanism that controls the throughput of each node according to a fair proportion of that link between source and destination that is shared by the highest number of nodes.
 
Khaled Amer
President, AmerNet Inc.
Architecture Analysis and Performance Modeling Specialists
Address:     13711 Solitaire Way, Irvine, CA 92620
Phone:        (949)552-1114                      Fax:     (949)552-1116           
e-mail:         khaledamer@xxxxxxx          
Web:           www.performancemodeling.com
 

 
----- Original Message -----
Sent: Tuesday, April 17, 2001 12:01 PM
Subject: Re: [RPRWG] Definition of terms - First set

Dear Khaled
 
Thank you for your comments. I will try to quantify maximum delay bounds for different kind of services.
 
Next try.
I will change the original definition
Bottleneck-link fairness: Fairness based on a mechanism that coordinates the ring access of only those nodes that use the same links for their packet transfers.
by
Bottleneck-link fairness: Fairness based on a mechanism that controls the throughput of each node according to a fair proportion of that link between source and destination that is shared by the highest number of nodes.
 
Best regards, Harmen
 
----- Original Message -----
Sent: Tuesday, April 17, 2001 7:02 PM
Subject: Re: [RPRWG] Definition of terms - First set

Harmen,
 
This is an excellent piece of work.
 
I have a couple of questions:
  • Do we want to quantify delay jitter instead of just mentioning variation in delay? I know it's a sore point in the literature, but maybe we can come up with something.
  • Not sure I understand your definition for Bottleneck-link fairness
Thanks.
 
Khaled Amer
President, AmerNet Inc.
Architecture Analysis and Performance Modeling Specialists
Address:     13711 Solitaire Way, Irvine, CA 92620
Phone:        (949)552-1114                      Fax:     (949)552-1116           
e-mail:         khaledamer@xxxxxxx          
Web:           www.performancemodeling.com