What is 802.3ae WAN-PHY?
Thank you for your intelligible feedback. Now I became convinced
that I speak English :-). I am happy to hear the Japanese style
here, Nicholl-san! But please feel free to say just Osamu, because
it helps me to trust (fake?) myself that I speak English.
Also, thanks to you, I became convinced that we have some issues of
clock tolerance compensation in SONET-framing that Rich has pointed
On the other hand, it seems to me that this community has consensus
that the ELTE, not the WAN-PHY with SONET framer, is the demarcation
point between SONET and Ethernet. In other words, WAN-PHY with SONET
framer or Uni-PHY with WIS (WAN interface sublayer) should not be
SONET. (All, please let me know if this is a wrong observation.)
Then why we need WAN-PHY or WIS other than ELTE?
The answer is in Mr. Paul Bottorff's slides in Albuquerque; the
router/SW requires minimal management capability of WAN.
Here I completely agree with Paul. This is indispensable to meet the
PAR scope "add parameters and mechanisms that enable deployment of
Ethernet over the Wide Area Network".
Then do we need SONET-frame between WAN-PHY and ELTE?
In my opinion, the answer is NO.
Once we have Mr. Shimon Muller's open-loop control to provide
OC-192c/VC-4-64c compatible MAC rate, my understanding of the need
for the SONET-framed PHY or WIS is limited to the OAM&P capability
supported by minimal overhead bytes in a SONET frame.
Here you have another solution 10GENIE; Layer-1 signaling by using
Assuming that 10GENIE can support the similar OAM&P to the ELTE, my
perspective says that 10GENIE would be cheaper than WAN-PHY and WIS;
no SONET framer (pointer manipulation), much less extra buffer for
OAM&P data insertion, no 9.95Gb/s CLK, no jitter-tolerance limitation.
I will shed light on this comparison in my up-dated 10GENIE proposal
Of course I have understood that 10GENIE has a tough problem indicated
by Mr. Steve Haddock; Who is going to define how to OAM&P?
My perspective says that IEEE 802 is the only candidate to be able to
define it. I know that this don't suit the traditional 802.3's taste,
but still I hope to have your support to define it. Otherwise we
will see the law of the jungle until some de facto OAM&P has
established; we will see wasteful investment to every potential loser
and local dialect cutting the market into pieces. We will fail to
catch a golden opportunity to unify LAN/WAN hardware for datacom at
10 Gb/s; and may degrade huge unified market potential.
In Ottawa, I will show you how 10GENIE OAM&P is simple and easy-
interoperable. I will restrict it to non-negotiable functions.
I think this may be simpler than the auto-negotiation with config-
register defined in 802.3z Clause 37.
All, any feedback on this matter would be greatly appreciated.
At 4:08 PM -0400 00.4.3, Gary Nicholl wrote:
> I agree with Ishida-san.
> I think we need to understand that there are two separate issues here.
> (1) clock tolerance/accuracy specifications (i.e. +/-100ppm, +/-4.6 ppm, etc)
> (2) jitter budget specifications (jitter generation, transfer and tolerance)
> The first one determines the lock range of any oscillators and phase look loops in the network. In SONET the worst case clock accuracy/tolerance is specified as +/- 20ppm and therefore every oscillator and clock recovery circuit in a SONET network should be able to lock on and hold to a +/- 20ppm signal.
> The second one, as Ishida-san points out is, effectively determines the maximum number of through-timed regenerators that can be traversed on an end-end SONET link to maintain a specified link bit error rate.
> These two specifications (i.e. clock tolerance/accuracy and jitter) are completely intendant. However from my experience in dealing with POS (packet over SONET) there is a tendency among some people to assume that they are related, in that a more accurate clock (say 4.6ppm rather than 20ppm) necessarily has better jitter performance. This is not the case. In fact SONET has a single set of jitter specifications (generation, transfer and tolerance) that are the same irrespective of whether an interface is clocked from a stratum 1 clock, a stratum 3 clock (4.6ppm) or a 'SONET minimum' clock (20ppm).
> As a reference point POS interfaces use a 20ppm clock and are fully compliant with the SONET/SDH jitter specifications in Bellcore GR-253 and ITU G.958.
> Gary ........................
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