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RE: [RPRWG] Is spatial reuse of A0 traffic possible?




More, each ringlet has its reserved bandwidth and it need a station
configurate each ringlet's reserved bandiwth. 

From Clause 10.5.2.2.1 Computation of total unreserved bandwidth:

ringInfo.unreservedRate[0] = LINK_RATE - resRate[0];
ringInfo.unreservedRate[1] = LINK_RATE - resRate[1];

In the event that the total unreserved bandwidth is less than zero on
either ringlet, an excess reserved rate defect shall be declared by
setting excessReservedRateDefect to TRUE. This defect is cleared when
the excess reserved bandwidth is removed.

So,when resRate[0] < LINK_RATE and resRate[1] < LINK_RATE, 
excessReservedRateDefect is FALSE.

But under excessReservedRateDefect is FALSE, if resRate[0]+resRate[1] >
LINK_RATE, when a link failure, a protection has occured. How to
guarantee the reserveed bandwidth? Beacause the total reserved bandwidth
is exceed the link rate.  

So I think the indicator of  excessReservedRateDefect is total reserved
bandwidth is exceed the LINK_RATE.

Best Regards
Jiangzhou

> -----Original Message-----
> From: owner-stds-802-17@xxxxxxxxxxxxxxxxxx 
> [mailto:owner-stds-802-17@xxxxxxxxxxxxxxxxxx] On Behalf Of 
> Fredrik Davik
> Sent: 2003Äê12ÔÂ22ÈÕ 18:25
> To: stds-802-17@xxxxxxxx
> Cc: steing@xxxxxxxxx; myilmaz@xxxxxxxxx; nuzun@xxxxxxxxx
> Subject: [RPRWG] Is spatial reuse of A0 traffic possible?
> 
> 
> 
> Clause 1.10 claims that spatial reuse of A0 traffic is 
> possible, while section 10.5.2.2.1 sums each station's 
> individual demand for A0 traffic when calculating the 
> reserved bandwidth on a ringlet, regardless of where the 
> individual stations will send A0 traffic.
> 
> Is there a conflict here?
> 
> Details to clarify the question are provided below...
> 
> In clause 1.10 Spatial reuse second paragraph on page 39, 
> lines 9-11 there is a statement:
> 
> ...There are restrictions on this form of bandwidth reuse, in 
> that some portions of the classA bandwidth (called 
> subclassA0, see 6.3) can be safely reused on non-overlapping 
> segments, but cannot be reclaimed by other service classes.
> 
> In clause 10.5.2.2.1 Computation of total unreserved 
> bandwidth, page 334, the function 
> ComputeTotalUnreservedRate() iterates through the topology 
> database entries for every station on a ringlet, reserving an 
> amount of bandwidth which is the sum of every station's 
> individual demand for reserved bandwidth.
> 
> My question is divided in 2 parts:
> 
> 1. Is spatial reuse of A0 bandwidth possible?
> 
> 2. What is the relationship between the ringlet{0,1}ReservedBW value
>    it sends out in its station bandwidth ATT (clause 10.5.2) and the
>    setting of the station's addRateA0 shaper setting? 
>    (addRateA0(ringletX) == ringletXReservedBW)?
> 
> My understanding of the current draft (3.0) is that a station 
> is only allowed to send the amount of A0 traffic on a ringlet 
> as configured by its addRateA0 shaper setting. Also, it seems 
> like the total reserved rate on a ringlet is the sum of each 
> station's individual demand for A0 traffic.
> 
> if (addRateA0(ringletX) == ringletXReservedBW), then I don't 
> see how it is possible to have spatial reuse of A0 traffic..
> 
> Best Regards, 
> Fredrik 
> ---------------------------------------------
> Fredrik Davik
>                  Phone:       +47 67 82 83 88
>                  Mobile:      +47 45 24 91 88
>                  Fax:         +47 67 82 82 01
>                  Switchboard: +47 67 82 82 00
> 
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