Hi Deborah, hi Spencer,

Spencer, thanks for adding on to this. Yes, that’s where my concern comes from.

I know that this only tries to use what's already done in RFC7471 (OSPF) and 
RFC7810 (ISIS) but the wording is used differently there. Sorry for being picky 
but as this is actually only a wording issue it can probably be resolved easy. 
The point is RFC7471 and RFC7810 carefully only talk about the current 
measurement value (which could have been measured over a long time period - and 
therefore is an average for this measurement time period). Or the talk about 
the actual utilization compared to the reserved bandwidth which is actually 
what is probably meant here. 

What’s about the following change to the abstract:

Either remove the brackets:

"The link bandwidth utilization is another
   important factor to consider during path computation.“

Or write down what Dhruv actually said:

„The link bandwidth utilization (the actual
   bandwidth used without any reserved bandwidth) is another
   important factor to consider during path computation.“

For other comments, please see may next mail in reply to Dhruv's mail.


> Am 15.09.2016 um 18:10 schrieb BRUNGARD, DEBORAH A <db3...@att.com>:
> Hi Spencer,
> This document is on how a PCE utilizes the IGP information of RFC7471 (OSPF) 
> and RFC7810 (ISIS). Both documents use the term “current” in their 
> definitions. And also use “actual”. For this document, we don’t want to 
> re-invent terms/definitions for already defined IGP information.
> Now I need to get to my “current” lunch before it’s not currentJ
> (Thanks for all the interest!)
> Deborah
> From: Spencer Dawkins at IETF [mailto:spencerdawkins.i...@gmail.com] 
> Sent: Thursday, September 15, 2016 11:43 AM
> To: BRUNGARD, DEBORAH A <db3...@att.com>
> Cc: Dhruv Dhody <dhruv.dh...@huawei.com>; Mirja Kuehlewind 
> <i...@kuehlewind.net>; The IESG <i...@ietf.org>; Dhruv Dhody 
> <dhruv.i...@gmail.com>; pce@ietf.org; 
> draft-ietf-pce-pcep-service-aw...@ietf.org; pce-cha...@ietf.org
> Subject: Re: [Pce] Mirja Kühlewind's No Objection on 
> draft-ietf-pce-pcep-service-aware-12: (with COMMENT)
> Hi, Deborah/Dhruv,
> On Thu, Sep 15, 2016 at 9:03 AM, BRUNGARD, DEBORAH A <db3...@att.com> wrote:
> Hi Mirja,
> Yes, thanks Mirja for you detailed review.
> As Dhruv noted, this is not representing an average utilization, but the 
> current bandwidth utilization. As Dhruv noted, we could swap this sentence in 
> the Abstract for the term later used in section 4.2.2 "actual". For me, 
> though, current bandwidth utilization is a common (simple) term used often by 
> operational folks, and it has a time element clarification. The document has 
> been reviewed quite extensively by others, so I'm not convinced about the 
> need to change this sentence of the Abstract. We'll discuss it more among the 
> Chairs and authors.
> Mirja may be having a post-telechat beer, and this is for her ballot 
> position, but I'm thinking that "time element clarification" is key here. If 
> "current bandwidth utilization" is measured on a scale of minutes or larger, 
> it usually doesn't freak out TSV folk, but if it's measured on a scale of 
> single-digit seconds or smaller, it usually does.
> At least, it freaks me out. I spent most of the time I was responsible AD for 
> one particular working group talking to them about how frequently they should 
> be adjusting cost maps based on bandwidth utilization and other, basically 
> instantaneous, transport metrics. The more frequently people make 
> adjustments, the more likely you are to see oscillation between paths that 
> you don't really want to see. For a distributed system, you're always basing 
> decisions on something in the past that may have changed since you found out 
> about it.
> I'll let Mirja take it from here on resolving her comment (because she might 
> be talking about something completely different), but wanted to chime in, so 
> that her comment doesn't become my comment, too.
> Thanks,
> Spencer

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