Subject: [PCN] New text in the CL and SM edge behaviour drafts

From: Tom Taylor <[email-masked]>
Date: Sat, 06 Mar 2010 11:09:18 -0500

I have added text to the edge behaviour drafts to deal with issues raised during 
the last meeting. I present this text here for your comment.

Tom Taylor

3.4.3.  Decision Point Action For Missing Egress Node Reports

    As mentioned in Section 3.2.2, the egress node MAY choose not to send
    reports for a configurable interval Tmax while it does not receive
    any PCN traffic for a given ingress-egress-aggregate.  However, if
    the decision point fails to receive reports for a given ingress-
    egress-aggregate for a configurable interval Tfail (of the order of 2
    * Tmax or less), it SHOULD cease to admit flows to that aggregate and
    raise an alarm to management.  This provides some protection against
    the case where congestion is preventing the transfer of reports from
    the egress node to the decision point.

3.5.  Summary of Timers

    This section has referred to three timers:

    o  Tcalc: a timer which SHOULD be configurable, specifying the
       frequency with which the PCN-egress-node calculates NM-Rate, ThM-
       Rate, and ETM-Rate and reports them to the decision point.  This
       timer is RECOMMENDED to be of the order of 100 to 500 ms.

    o  Tmax: a configurable timer, specifying the maximum amount of time
       between successive reports from the PCN-egress-node for a given
       ingress-egress-aggregate.  This is RECOMMENDED to be of the order
       of one second.

    o  Tfail: a configurable timer, specifying the maximum amount of time
       between successive reports for a given ingress-egress-aggregate
       received at the decision point, after which the latter SHOULD
       cease to admit flows to the aggregate concerned and raise an alarm
       to management.  This is RECOMMENDED to be of the order of 2 * Tmax
       or less.