Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: [802.3_NGECDC] Definition of "Breakout"?



Jeff,

Let me try a different tact –

For all of these instances – the specifications that would exist on each different pair or optical fiber should be the same –

  • AUI
  • Related PHYs
    • Backplane
    • Twin-ax cabling based on multiple different pairs
    • SR optics based on parallel MMF
    • DR optics based on parallel SMF

 

So the specification for each should be essentially the same – just varying the number of different pairs or fiber.

 

In the case of F/L/E we are looking at different specifications for the different number of lanes, as the associated mux/demux loss would vary, based on the number of optical signals being muxed /demuxed together.

 

Does this help ?

 

John

 

From: Jeffery Maki <jmaki@xxxxxxxxxxx>
Sent: Thursday, August 20, 2020 1:56 PM
To: jdambrosia@xxxxxxxxx; STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: RE: [802.3_NGECDC] Definition of "Breakout"?

 

John,

 

Let me ask a question first.

 

I your case (a), do you mean the individual interfaces will support ingress signals on separate time domains within +/-100ppm or are you simply looking at the fact that there is exact alignment with the PMD definition of a lower speed of Ethernet where any time domain support is an implementation detail?

 

Jeff

 

 

Non-Juniper

From: jdambrosia@xxxxxxxxx <jdambrosia@xxxxxxxxx>
Sent: Thursday, August 20, 2020 10:42 AM
To: Jeffery Maki <jmaki@xxxxxxxxxxx>; STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: RE: [802.3_NGECDC] Definition of "Breakout"?

 

[External Email. Be cautious of content]

 

Suggestion?

 

From: Jeffery Maki <jmaki@xxxxxxxxxxx>
Sent: Thursday, August 20, 2020 1:30 PM
To: jdambrosia@xxxxxxxxx; STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: RE: [802.3_NGECDC] Definition of "Breakout"?

 

John,

 

I chose my words carefully. As others have commented, they understand things in an operational sense from the implementations they see. Constricting the definition of “breakout” from its broader industry meaning does not seem like a good start. Perhaps use a different word that doesn’t come with so much “baggage.”

 

Jeff

 

 

Non-Juniper

From: jdambrosia@xxxxxxxxx <jdambrosia@xxxxxxxxx>
Sent: Thursday, August 20, 2020 10:22 AM
To: Jeffery Maki <jmaki@xxxxxxxxxxx>; STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: RE: [802.3_NGECDC] Definition of "Breakout"?

 

[External Email. Be cautious of content]

 

Jeff

Please keep my perspective in mind right now – I am trying to draft the CFI and scope of a new standard effort in the IEEE 802.

 

Not the scope of an implementation in an industry MSA.

 

Different requirements for each.  And I hope all recognize the challenge.

 

John

 

From: Jeffery Maki <jmaki@xxxxxxxxxxx>
Sent: Thursday, August 20, 2020 1:19 PM
To: jdambrosia@xxxxxxxxx; STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: RE: [802.3_NGECDC] Definition of "Breakout"?

 

John,

 

It is hard at this point to separate out conceptually the implementation from the abstract PHY. One can devise a superset module that supports a number of compliant PHY implementations with some being parallel fiber based and others being duplex fiber based. One’s choice of focus on your (a) or your (b) is their choice of favorite point of view. Both (a) and (b) are supported equally well by the module.

 

Jeff

 

 

Non-Juniper

From: John D'Ambrosia <jdambrosia@xxxxxxxxx>
Sent: Thursday, August 20, 2020 9:32 AM
To: STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_NGECDC] Definition of "Breakout"?

 

[External Email. Be cautious of content]

 

All – conversation is good, and highlighting an issue that needs to be addressed.

 

There appears to be a trend of

  1. Breaking out a standards based PHY into the individual channels of the PHY into independent links
  2. An industry or vendor defined implementation that gangs a number of independent links together.

 

I can see a path to relating Item A to be within scope of Beyond 400 GbE effort.  I am not seeing that same path for Item B. 

 

John

 

 

 

From: Ted Sprague <tsprague@xxxxxxxxxxxx>
Sent: Thursday, August 20, 2020 12:25 PM
To: STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_NGECDC] Definition of "Breakout"?

 

I’m used to the second definition (independent PHYs grouped in the same MSA, common interface for management).

 

In the first case, the module may support a unified mode or multiple individual modes – but only the second is referred to as ‘breakout’.

 

Thanks Ted

 

From: David Ofelt <00000d9f58951f93-dmarc-request@xxxxxxxxxxxxxxxxx>
Sent: Thursday, August 20, 2020 8:50 AM
To: STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_NGECDC] Definition of "Breakout"?

 

CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe.

 

I think there are two different concepts that end up being colloquially referred to as breakout.  The first is that case you detaiil below- a set of parallel media lanes that can be grouped in various ways- either as a single unified PHY or as a number of slower PHYs.  The other case is a module that happens to hold a number of PHYs that are completely independent- like a QSFP-DD/OSFP module that has 4 x 100GBASE-LR optics. 

 

I’m Ok with declaring that “breakout” just covers the first case and your list is a good start at scoping the definition, but if we do that, I’d like us to figure out a name for the other case.  I find that when I talk to people about modules- it is important to clearly address both cases, since many folks have only one of the cases in mind and conversations can get confusing. 


I am also Ok with defining “breakout” to cover both cases, but then we can make that explicit in the definition.

 

--

DaveO

 

 

From: John D'Ambrosia <jdambrosia@xxxxxxxxx>
Reply-To: "jdambrosia@xxxxxxxxx" <jdambrosia@xxxxxxxxx>
Date: Thursday, August 20, 2020 at 06:03
To: "STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx" <STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx>
Subject: [802.3_NGECDC] Definition of "Breakout"?

 

[External Email. Be cautious of content]

 

All,

As I explore the scope for the Beyond 400 GbE effort, I have been having a number of conversations related to “breakout”

 

While we all discuss it – I have never seen some actual formal definition that is agreed upon within 802.3.  So I would like to get some input.

 

I am going to start with breakout actually does and solicit input before proposing some definition to potentially use.

 

I see break out of the following –

  • AUI
  • Related PHYs
    • Backplane
    • Twin-ax cabling based on multiple different pairs
    • SR optics based on parallel MMF
    • DR optics based on parallel SMF

 

FR / LR / ER optics – I don’t see as being part of breakout.

 

Thoughts?

 

John


To unsubscribe from the STDS-802-3-NGECDC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGECDC&A=1


To unsubscribe from the STDS-802-3-NGECDC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGECDC&A=1


To unsubscribe from the STDS-802-3-NGECDC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGECDC&A=1


To unsubscribe from the STDS-802-3-NGECDC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGECDC&A=1


To unsubscribe from the STDS-802-3-NGECDC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGECDC&A=1