Re: [STDS-802-3-EPOC] Burst Markers
Hi Raanan,
Thanks for the email. I agree that we need to understand the overhead for the burst markers. I would like to keep it small but it is also important that the detection is reliable. I think that MMP could be solved with the burst markers. We are working on a proposal for the markers that we think will work for both. I believe that Juan (Qualcomm) is working on a marker proposal with the same objective.
To be honest, I haven't spent much time considering the dynamic TDD case with markers. I like the idea of dynamic TDD and had proposed it in an earlier presentation. Can you give me a few more details on the challenges of a dynamic TDD with burst markers? Why wouldn't it be a good solution versus a MAP?
Thanks,
Ed....
From: Raanan Ivry [mailto:raanan.ivry@xxxxxxxxxxxx]
Sent: Tuesday, February 19, 2013 2:37 AM
To: 'Victor Blake'; Ed (Edward) Boyd
Cc: STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx
Subject: RE: [STDS-802-3-EPOC] Burst Markers
I agree with your answers/comments.
It's true that in the new wireless standards there is no strict line between MAC and PHY.
In any case, when we decide about a solution, we need to compare it with other option and to verify that we do not lose too much.
The map we are talking about is also relevant to some other issues we are dealing with, like MMP and dynamic TDD.
BTW, if we want to adopt Dynamic TDD, Burst Markers will not give a good solution.
Thanks,
Raanan
________________________________
From: Victor Blake [mailto:victorblake@xxxxxxxxxxxxxxx]<mailto:[mailto:victorblake@xxxxxxxxxxxxxxx]>
Sent: Monday, February 18, 2013 9:14 PM
To: STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx<mailto:STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx>
Subject: Re: [STDS-802-3-EPOC] Burst Markers
The map approach is what is used in some wireless protocols as well. It can be very effective when there are a wide range of frequencies (channels) in use and the allocations of services across them changes over time.
The gate can be thought of as a two dimensional means (time and LLID), the map is really a three dimensional gate, time, channel, LLID. In this way, the map is performing the same function as a gate.
In other words, it's only adding one more parameter to the gate to make a map.
-Victor
From: Ed (Edward) Boyd [mailto:ed.boyd@xxxxxxxxxxxx]<mailto:[mailto:ed.boyd@xxxxxxxxxxxx]>
Sent: Monday, February 18, 2013 1:44 PM
To: STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx<mailto:STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx>
Subject: Re: [STDS-802-3-EPOC] Burst Markers
Hi Raanan
Thanks for the email. It is certainly possible to build and send MAPs as done in other standards. This type of solution is far from the current Ethernet/EPON standard. The PHY doesn't process the GATE frames in the current standard and there isn't burst information signaled from the MAC to the PHY. The GATEs are sent unicast with delay compensation in the start time. It would challenging to have a PHY rewrite the frames and figure out the boundaries of the GATEs so it could construct the MAP.
While laser ON/OFF doesn't exist in EPoC, other burst overheads do exist. I would like EPoC to have the same or less burst overhead than EPON so I use the laser on/off and sync time from EPON as a reference point for comparison.
In short, The MAP is an option for a new standard but it really isn't for an EPON over Coax. I think the marker will be simple and allow full compatibility with the EPON standard and layering.
On the overhead, I think that it can be low based on discussions with our PHY team. It could be just a few symbols in a small number of carriers. We are working proposals on the details and are open to suggestions. I think that the shortened last code word will be the largest burst overhead for EPoC.
Hope that helps
Ed
Sent from my iPhone
On Feb 18, 2013, at 8:01 AM, "Raanan Ivry" <raanan.ivry@xxxxxxxxxxxx<mailto:raanan.ivry@xxxxxxxxxxxx>> wrote:
Hi Ed,
In your presentation you suggested the use of Burst Markers.
There is another option: All the information (a full map) about teh burst timing and frequencies can be sent in a Gate message by the CLT.
There are differences between EPON and EPoC which may permit such attitude:
1. Symbol size (EPoC) >> bit size (EPON)
2. There is no such thing as laser on/off time in EPoC
3. CLT-CNU synchronization is not a problem
We need to understand:
1. Why we need those Burst Markers
2. What the penalty (overhead) we are going to pay is.
Raanan
________________________________
________________________________
________________________________________________________________________
To unsubscribe from the STDS-802-3-EPOC list, click the following link:
https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-EPOC&A=1