[802.3_EPOC] 回复: Re: [802.3_EPOC] What is the problem with the EPoC converter, and what is the CLT?

[姚永 <yy0412@xxxxxxxxx>]

抱歉，我没有学过英语，只好用中文答复。

“桥”应该是二层、也就是数据链路层（包括MAC）的设备，博通专利中的名称是CMC，意思是“Coaxial Media Converter”——物理层的转换。我的上一个邮件实际是对单纯物理层转换提出了疑问。但是我们希望MAC层不要分成两段——光和电各一段，也就是不希望当中有个桥接设备。在中国，EoC最初就是以“缆桥”命名的，其短板就是不能端到端。我们认为，解决的方案之一就是扩展EPON MPCP协议，在CMC（或者OCU、或者ECB，叫什么不重要）变换一下帧格式，也许还要增加一些预测帧，同时对数据存储转发，但是保持OLT对CNU的控制、管理、调度。

 

2012-03-04

---

姚永

---

发件人：Geoff Thompson

发送时间：2012-03-04 08:09

主题：Re: [802.3_EPOC] What is the problem with the EPoC converter, and what is the CLT?

收件人：STDS-802-3-EPOC

抄送：

 

David-
As I discussed in my earlier message,
your statement below:

‘Bridge’ is actually the more generic term.

is not correct.
In IEEE 802, a "bridge" is not a generic term.
Rather, it is a specific type of device whose configuration in standardized in 802.1

Best regards,
    Geoff Thompson

On 23//12 11:42 PM, Barr, David wrote:

From: David Barr <David.Barr@xxxxxxxxxxxx>

Date: Fri, 2 Mar 2012 17:01:43 -0800
To: "Salinger, Jorge" <Jorge_Salinger@xxxxxxxxxxxxxxxxx>, EPoC Study Group <STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx>
Subject: RE: [802.3_EPOC] What is the problem with the EPoC converter, and what is the CLT?

Yes, I agree with Jorge, Valy, Satish & Mr. Yao (SARFT), that a Bridge makes more sense.

‘Media Converter’ implies a PHY-layer hub, which will not be optimum for coax.

MACs are just digital logic, which are fully exposed to Moore’s Law.

Why preserve the MAC, if it becomes a vanishingly small part of the solution?

Particularly when preserving the sub-optimum MAC ruins the economics on coax.

‘Bridge’ is actually the more generic term.

The advisable approach is to bridge to coax-optimized technology,

with IEEE focusing on specifying the manageability & provisioning across that bridge.

-Dave

---