Question for Carol Kaur

[CoryKS]

I wasn't sure whether to put this in The Computer Room, The Study, or Horror Stories. It's a technical question, but the story behind it is grim.

You may have heard about a murder that took place here this week. An 18-year-old woman was abducted and killed by a scumbag who, it turns out, lived about a mile down the road from me. Her body was found near a lake over on the Missouri side, and it is the method they used to find it that I want to talk about.

The media reported that the police focused on this area because of a "ping" received from a cell tower in the area. This ping was from the girl's boyfriend calling her around 8:00 Saturday, the night she disappeared. It was Wednesday when they were able to determine a location. I don't have the link, but an officer was questioned about why it took four days to do this and his response was that they had immediately began looking at the cell phone records and that the reason it took that long was because of the volume of data they had to look at. My impression was that they were looking for the one needle in a haystack of cell phone calls, and I was curious about how this needle might be made easier to see.

My question is this: If a huge number of calls are placed to one cell phone, would this make it easier to locate the end point of the call? I'm talking about an anomalous number of hits, like a DoS attack but with cell phones. I have no knowledge of telephony, so forgive me if this is a stupid question. :asian:

 

[Carol]

I wasn't sure whether to put this in The Computer Room, The Study, or Horror Stories. It's a technical question, but the story behind it is grim.

You may have heard about a murder that took place here this week. An 18-year-old woman was abducted and killed by a scumbag who, it turns out, lived about a mile down the road from me. Her body was found near a lake over on the Missouri side, and it is the method they used to find it that I want to talk about.

The media reported that the police focused on this area because of a "ping" received from a cell tower in the area. This ping was from the girl's boyfriend calling her around 8:00 Saturday, the night she disappeared. It was Wednesday when they were able to determine a location. I don't have the link, but an officer was questioned about why it took four days to do this and his response was that they had immediately began looking at the cell phone records and that the reason it took that long was because of the volume of data they had to look at. My impression was that they were looking for the one needle in a haystack of cell phone calls, and I was curious about how this needle might be made easier to see.

My question is this: If a huge number of calls are placed to one cell phone, would this make it easier to locate the end point of the call? I'm talking about an anomalous number of hits, like a DoS attack but with cell phones. I have no knowledge of telephony, so forgive me if this is a stupid question. :asian:

Very sorry to hear the news. My prayers for her family and friends. :asian:

It's not a stupid question at all, but it is a very complex.

Ultimately, it probably would not help. I can get in to why if you like although it will be a rather geeky explanation.

The biggest constraints to such a project are...there aren't many people around with the engineering skills to do it, it is a one-person job (can't be delegated to a team), and the data involves a zillion cross references trying to make sense of gigs and gigs of hex dumps such as this:

02 01 DC AF 08 02 00 22 05 A1 04 03 90 90 A3
03 A9 83 81 1E 02 8A 81 6C 0D 00 83 30 18 C9

RF signals were never meant to track people therefore the data required for a project like that must be deeply (and manually) dug in to. It takes a person with an eye for pattern matching.

A more effective step would be to help make sure those close to you have cell phones that activate GPS on emergency calls.

 

[CoryKS]

Thank you for your reply, Carol. I figured it had to be something like a hex dump. I guess I was just hoping that by making a lot of calls to the same phone a pattern would emerge faster, but I guess that's not feasible.

Regarding the GPS - does that only work for outgoing emergency calls, or can it be activated by an incoming call? My understanding is that the signal used to locate her came from a call her boyfriend made and that she was unable to accept the call or send calls.

 

[Andrew Green]

I don't think I'd want a phone that a GPS got activated on based on incomming calls. Seems like a big privacy issue there...

I understand that in a few rare cases being able to located people quickly and easily based on there cell phone would be handy, but thats a lot of information about people to be tracking, and a huge potential for abuse.

 

[MA-Caver]

I don't think I'd want a phone that a GPS got activated on based on incoming calls. Seems like a big privacy issue there...

I understand that in a few rare cases being able to located people quickly and easily based on there cell phone would be handy, but thats a lot of information about people to be tracking, and a huge potential for abuse.

Very HUGE... there are people trying to find people all the time out there... not all with good intentions. Irate ex-husbands/bf's trying to find "her" and so forth.
But if a person abducted has a chance to even press send after dialing an emergency number the chance to find them rises.
One would think most potential abductors would remove the vic's cell phone as quickly as possible. At which point the it all becomes moot because there's no vic with the phone.

That they found the girl (and it's a sad loss indeed) as quick as they did was largely because the perp was careless and just dumped the body after he was through. Says to me a crime of passion/revenge, taking their mad out on them and being through.

There's not too many suspects and they (maybe) have the perp on tape so catching him wouldn't be too difficult unless he goes to ground and quickly.
Then again the guy could be just another customer and just happened to walk out of the store about the same time she did... happens to me... I walk out behind other customers all the time... does that make me a stalking criminal?
This is something the D.A. will have to contend with but hopefully the perp is stupid enough to leave behind enough DNA evidence.

 

[CoryKS]

I don't think I'd want a phone that a GPS got activated on based on incomming calls. Seems like a big privacy issue there...

I understand that in a few rare cases being able to located people quickly and easily based on there cell phone would be handy, but thats a lot of information about people to be tracking, and a huge potential for abuse.

Well, yes, I suppose it would be, but I wasn't suggesting transmitting GPS coordinates to the requesting phone. I was requesting clarification on the Carol's recommendation about GPS phones.

 

[Carol]

oops - mistyped.

 

[Carol]

Thank you for your reply, Carol. I figured it had to be something like a hex dump. I guess I was just hoping that by making a lot of calls to the same phone a pattern would emerge faster, but I guess that's not feasible.

It's a really good thought, that's for sure. The problem is in the dynamics of the cellular usage. A call made to an endpoint not necessarily received by the endpoint. If the power is off or in certain condition of engagement, there would be no RF data generated, which is what the engineer is trying to look for.

If the phone was ON (but the subscriber was not able to take the call), then that would generate RF data that could be tracked because the cell phone would be receiving an alerting signal from the neighboring tower sites. If the phone was off, that would just generate data that largely either has no effect or ends up muddying the process.

The problem with a DOS-style attacks is they generally take the phone off the network faster, either because of the battery wearing out, or because the phone is shut down by someone. I'm guessing that at 8PM that Saturday night, the boyfriend did not definitively know that his girlfriend was a victim of foul play, he just knew he wasn't around so he was calling her trying to find out where she was.

Regarding the GPS - does that only work for outgoing emergency calls, or can it be activated by an incoming call? My understanding is that the signal used to locate her came from a call her boyfriend made and that she was unable to accept the call or send calls.

There are two implementations of GPS. Most new cell phones have GPS for outgoing emergency calls only, however some PDA-phones (such as the blackberry) have GPS navigation capability and have the can toggle the GPS settings from Emergency Calls Only to on all the time.

Would the GPS have helped after the fact in this particular case - no, not given the actions. But if the woman had been able to call 911 when she was in trouble (even a 1-touch dial to the number and not saying anything to the dispatcher) that would have given law enforcement more data to work for.

 

[CoryKS]

See, I knew I was talking to the right person. Thanks, Carol!