RE: [Geopriv] ResponseTime

From: Dawson, Martin ^lt;Martin.Dawson@andrew.com>
Date: Tue Aug 28 2007 - 18:20:24 EDT

Yes thanks! ________________________________ From: Roger Marshall [mailto:RMarshall@telecomsys.com] Sent: Wednesday, 29 August 2007 7:39 AM To: Dawson, Martin; Brian Rosen; Stuard, Doug; peter_blatherwick@mitel.com; Winterbottom, James Cc: GEOPRIV Subject: RE: [Geopriv] ResponseTime Hey there Martin: There is such a system in use today, and what I can do is offer to provide a more detailed explanation in text of how this works, which would provide a better basis for discussion. -roger marshall. ________________________________ From: Dawson, Martin [mailto:Martin.Dawson@andrew.com] Sent: Tuesday, August 28, 2007 2:21 PM To: Roger Marshall; Brian Rosen; Stuard, Doug; peter_blatherwick@mitel.com; Winterbottom, James Cc: GEOPRIV Subject: RE: [Geopriv] ResponseTime Hi Roger, Can you provide an example of a real system that generates these 7 coefficients? That is, what is being measured and how does this resolve into the discrete coefficients and what are the significance of these coefficients? I'm trying to understand where you're coming from but it's a little too cryptic for me at the moment. Cheers, Martin ________________________________ From: Roger Marshall [mailto:RMarshall@telecomsys.com] Sent: Wednesday, 29 August 2007 6:51 AM To: Brian Rosen; Stuard, Doug; peter_blatherwick@mitel.com; Winterbottom, James Cc: GEOPRIV; Dawson, Martin Subject: RE: [Geopriv] ResponseTime One way to reduce complexity (may not sound like it at first) is to: -- program: one standardized function (produces 7 coefficients from a couple of inputs) to describe any common shape -- input: a combination of confidence, uncertainty (max), and timing (max) as input variables -- output: the 7 coefficients, plug them in and present the location/shape The client gets to control everything through input variables, whether it's an end device, middlebox, or PSAP client. One client (e.g., the end-device) can use a low time, a low confidence to get routing information, gets the coefficients - and the PSAP client reuses the conveyed coeff's along with their 'standard' 95% confidence input value. -roger marshall. ________________________________ From: Brian Rosen [mailto:br@brianrosen.net] Sent: Tuesday, August 28, 2007 1:01 PM To: Roger Marshall; 'Stuard, Doug'; peter_blatherwick@mitel.com; 'Winterbottom, James' Cc: 'GEOPRIV'; 'Dawson, Martin' Subject: RE: [Geopriv] ResponseTime Okay, but what are you proposing? Having a standardized value is so much more useful than the absolute number. Generally, every user I ever talked to was unable to use confidence unless all sources gave them the same confidence. If they varied, then they were forced to ignore it; nothing they could think of doing: displaying, calculating, dispatching, routing... could change based on the value of confidence. If you have the same value, then at least you can compare two locations from different sources and they mean the same thing. You still can't use confidence for displaying, calculating, dispatching or routing. ________________________________ From: Roger Marshall [mailto:RMarshall@telecomsys.com] Sent: Tuesday, August 28, 2007 3:53 PM To: Brian Rosen; Stuard, Doug; peter_blatherwick@mitel.com; Winterbottom, James Cc: GEOPRIV; Dawson, Martin Subject: RE: [Geopriv] ResponseTime This gets to the nagging problem of how good is 'good enough'? Determining elements can certainly provide position, based on input of 67% confidence, but they can also do better. If you're willing to wait a few more seconds, they can churn out a more accurate result based on a 90 or 95% input value. In fact, maybe they'll have to use 95% to get the level of precision that some regulatory agency will ask for someday. By providing confidence value as an input to these mechanisms, you can achieve location hiding (to some degree) as well. -roger marshall. ________________________________ From: Brian Rosen [mailto:br@brianrosen.net] Sent: Tuesday, August 28, 2007 12:45 PM To: 'Stuard, Doug'; peter_blatherwick@mitel.com; 'Winterbottom, James' Cc: 'GEOPRIV'; 'Dawson, Martin' Subject: RE: [Geopriv] ResponseTime James pointed out to be that PIDF-LO profile actually does say use 67%. While I'd much prefer 90 or 95%, a single standardized value beats any set of values hands down. Brian ------------------------------------------------------------------------------------------------ This message is for the designated recipient only and may contain privileged, proprietary, or otherwise private information. If you have received it in error, please notify the sender immediately and delete the original. Any unauthorized use of this email is prohibited. ------------------------------------------------------------------------------------------------ [mf2]

_______________________________________________
Geopriv mailing list
Geopriv@ietf.org
https://www1.ietf.org/mailman/listinfo/geopriv
Received on Tue, 28 Aug 2007 17:20:24 -0500

This archive was generated by hypermail 2.1.8 : Tue Aug 28 2007 - 18:22:26 EDT