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stds-80220-eval-criteria: RE: 802.20 Fairness Criteria




Hi Farooq,

Thanks for your reply. The outage criteria in the 1xEV-DV evaluation
methodology document (Appendix C) defined the per-user and system outage, in
terms of probability that the user's short-term FER exceeded the per-user
outage threshold, and the probability that the percentage of users that were
in outage exceeded the system outage threshold respectively. How would you
relate that to the outage constraint of 9.6 kbps, as you have mentioned in
your email?

Table 1 and figure 1 of your contribution showed that there should be no
user (cdf=0.0) with normalized throughput below 0.2, or 10 kbps in the
example in your email. But the paragraph below the table stated that the
percentage of users in outage (i.e., with normalized throughput below 0.2)
shall be below 2%. Should the CDF corresponding to the normalized throughput
of 0.2 be 0.02 instead of 0.0, for consistency?

Best regards,
Anna.

-----Original Message-----
From: Khan, Farooq (Farooq) [mailto:fkhan1@lucent.com] 
Sent: Wednesday, October 29, 2003 2:48 AM
To: 'Lai-King Tee'
Cc: 'Joseph Cleveland'; 'Jin-Weon Chang'; aappaji@sta.samsung.com
Subject: 802.20 Fairness Criteria

Anna,

Thanks for your comments.
You are right, the criteria that I proposed is more stringent than one in
1xEV-DV. I came up with this criteria based on my experience of using DV
criteria. It turns out that the DV criteria is "too relaxed". In fact the DV
criteria was developed to discourage people not to use "Max C/I" type of
schedulers for artificially boosting the system capacity. 

The new criteria still allows up to a factor of 9 difference between the
best and the worse user throughput (and delay). For example, the criteria is
satisfied if the throughputs are uniformly distributed between 10-90Kb/s
with average throughput of 50Kb/s. A normalized throughput of 0.2 means user
average throughput of 10Kb/s (0.2*5Kb/s). 

I decided to use normalized throughput as outage criteria in contrast to an
absolute number (like in DV we have 9.6Kb/s as the outage constraint) in
order to simplify the specifications. Looking at the above example, users
with throughput below 10Kb/s would be in outage.

Please let me know if you have any other questions.

Farooq

-----Original Message-----
From: Lai-King Tee [mailto:a.tee@samsung.com]
Sent: Tuesday, October 28, 2003 7:22 PM
To: 'Khan, Farooq (Farooq)'
Cc: 'Joseph Cleveland'; 'Jin-Weon Chang'; aappaji@sta.samsung.com
Subject: RE: stds-80220-eval-criteria: Evaluation Criteria Conference
Call - Tuesday, 28 October 2003, 6 :00-8:00 PM Eastern


Dear Farooq:

I was on the conference call earlier today. I have taken a closer look at
the fairness criteria, and compared it with the one described in 1xEV-DV
Evaluation methodology document. The fairness criteria in 1xEV-DV had an
offset of 0.2 to the left of the one that you have proposed. Would you mind
to explain the reason for the difference? The current fairness criteria seem
to be more stringent in the way that you have proposed. 

The other question is about the minimum normalized throughput on your
fairness criteria is 0.2, while the outage would happen when the percentage
of user with normalized throughput below 0.2 is greater than or equal to 2%.
Is there any connection between those two numbers, i.e., cdf at 0.2 vs
outage percentage? 

Thanks very much for your time.

Best regards,
Anna.