| Thread Links | Date Links | ||||
|---|---|---|---|---|---|
| Thread Prev | Thread Next | Thread Index | Date Prev | Date Next | Date Index |
|
John, I disagree. The term “breakout” is used in a general sense whenever a module can be put into use as four independent interfaces supporting ingress signals on four independent time domains. The choice of reach does not change this understanding. The following modules are in the market or in progress to be in the market.
QSFP+ for 4 x 10GBASE-LR QSFP28 for 4 x 25GBASE-LR QSFP-DD for 4 x 100GBASE-LR1 and also QSFP-DD for 4 x 100GBASE-FR1 The QSFP-DD for 4 x 100GBASE-FR1 is also known as 400G-DR4+. It can also be used to support 400GBASE-DR4 with 500 meters of parallel cabling. The QSFP-DD for 4 x 100GBASE-LR1 is also known as 400G-DR4++. It can also be used to support 400GBASE-DR4 with 500 meters of parallel cabling but is a less likely use case. The relevance of breakout to the IEEE 802.3 process is when the high-capacity module supporting breakout is thought to be the prevalent implementation of the PMD for broad-market potential instead of a single implementation of the PMD in
a given form factor. In companion with this is the definition of a multi-port MDI with demarcation of which Tx and which Rx go together. These definitions are usually left for form-factor MSAs to define. The QSFP-DD MSA defines MPO and four separate SN/MDC
duplex connectors to support quad-port breakout. The QSFP-DD for 4 x 100GBASE-FR1 AKA 400G-DR4+ using SN connector is an example.
Jeff From: David Ofelt <00000d9f58951f93-dmarc-request@xxxxxxxxxxxxxxxxx>
[External Email. Be cautious of content] 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.
-- DaveO From: John D'Ambrosia <jdambrosia@xxxxxxxxx> [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 –
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 |