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Your description is correct. If you're asking how the WAN PHY will react to
Line/Path AIS, the pointer processor will detect AIS-P and the all ones
signal will be passed from the WIS up to the 66/64 decoder, which will lose
sync (e.g. LOD defect, Loss Of Delineation), then the MAC will see the
ReceiveDataValid line inactive & discard frames.
From: Osamu ISHIDA [SMTP:ishida@xxxxxxxxxxxxxxxxxxx]
Sent: Friday, June 09, 2000 6:24 AM
To: Martin, David [SKY:1I63-M:EXCH]
Subject: Re: WIS OH
Could you help me to understand how WAN-PHY and ELTE would react on
SONET AIS (Alarm Indicaton Signal)?
When we have cable cut in SONET infrastructure, the SONET side of
the ELTE will receive either Line-AIS or Path-AIS.
Line-AIS: all '1' in Line OH and SPE payload.
generated by the regenerator who detect upstream cable cut.
detected by the last 3 bits in K2 (at least 3 consecutive '111')
Path-AIS: all '1' in AU pointer and SPE payload.
generated by LTE who detect upstream cable cut.
detected by the all '1' in H1&H2 at least 3 consecutive frames.
At 5:13 PM -0400 00.6.1, David Martin wrote:
> Gary, Osamu,
> Regarding the need for B2/M1. My thinking behind proposing B1 & B3/G1
> only is that B1 is sufficient for fault isolation, and B3/G1 can serve
> adequately for performance monitoring in the typical BER operating
> range (a carrier can tap in with Intermediate Path Performance
> Monitoring - IPPM).
> Regarding the need for K1-2. I was thinking that protection switching
> in the LAN is not a traditional feature. In the WAN, optical layer
> protection could be used.
> Roy has suggested using J1 Path Trace. I can see value in that.
> But I believe if we add more OH beyond the WIS proposal (i.e. B1,
> B3/G1, J0), save J1, we'll be crossing the line from compatible
> to compliant & adding unnecessary cost.
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