All modern ECUs have a "limp home" mode activated if they lose one or more sensors. Basically they run a default setting on ignition and fuel injection that allows the engine to continue to operate.
If your MIL (Malfunction Indication Light) lights up on your dash, you are probably in limp home mode./MF
Ripping the GPS and/or phone antenna may not be enough.
1. If you are in a good AMPS coverage area, the radio will get a signal even without an antenna.
2. If there is no GPS signal available, the car is still able to temporarily track itself by measuring the wheel speed of the left and right (non-drivetrain) wheels and do dead reckoning calculation based on speed, time and direction (left/right differences == turning car). This method is only valid for a while since the errors add up over time. Also, not all cars have this feature either.
I forgot to mention that the article's description of the eavesdropping blocking the line for emergency calls points to a incorrectly designed telematics system.
What should happen is that any non-emergency call is aborted when a higher level event, such as an airbag deployment, occurs.
A few telematics systems lets you silently call upp the vehicle and eavesdrop using the handsfree functionality, but most don't. Some of the protocols supports it, while the vehicle implementation of it does not.
What a call center operator can always do, however, is silently track your car. It usually works by calling up the vehicle over Verizon's WIN4 net, transmit authentication codes and a request to track the car's progress. Every five-fifteen minutes thereafter, the car will call up and transmit a GPS log to the call center.
Remote door unlock is often also a trivial matter.
No, you cannot call up and hijack the vehicle from the ordinary phone network since all WIN4 subscriptions have an areacode of 500, rending them unreachable from any ordinary phone. Calling out to them is a long and tedious process. On top of this, every vehicle usually have a unique passcode generated when the car is built. A list of these passcodes are then sent directly to the call center who uses them to access the cars.
No, you cannot reprogram the 800 number dialled by the vehicle in case of a crash or other event. The number is setup in the WIN4 network. No matter what number you are trying to get to from the handset, you will end up at the same DNIS.
I work with Telematics as a software systems architect.
The main problems we encounter are:
Coverage. Only AMPS can provide any kind of decent coverage in the states. This means 1200 BPS and heavy error correction. We use everything from DTMF tones to stripped down V.27 (fax) data bursts to get the message across. No. Sattelites are too expensive.
Driver attention. If you are driving a vehicle, you should not play around with an interface. There are also regulations on what you can put on the dashboard when it comes to screens etc. Services has to be kept extremely simple. We are just learning to do voice recognition in an automtive environment with noise, radio, screaming kids etc.
Tech cycles. A car is supported for approx. 10 years by its manufacturer. Which mobile standard should we use, given that GSM, GPRS, or CDMA gets the right coverage? Forget 802.11 where the vehicles act as nodes in a network. 802.11 only works up to 20 km/h
Conservatism. The automotive industry have change cycles measured in years, if not decades. It's very hard to match up the mentality of that industry with the dynamic and unstable nature of the computer and wireless business.
Today everyone are aiming at deploying boring, basic services such as theft notification with vehicle tracking, roadside assistance, remote door unlock, crash notification etc. BMW in Europe is probably the leader where the roadside assistance call center can update a map with routes that is displayed in the new 700 series. All European solutions, BTW, uses GSM and SMS messages to transmit data. Its store and forward makes it ideal for low bandwidth mobile communication.
Next generation of services will include traffic, food, gas, service info and geo-ads. Cool things like streaming video is faaar down the road. When we are playing around in the lab, we look at the possibility of using USB keys as storage (MP3 etc) and ignition keys. We are also looking into the possibilities of using max-bandwidth/least-cost routing that switches between different technologies depending on what coverage you currently have. You would then have a fixed IP-address that acts as a proxy and forwards packets to the vehicle using CDPD, SMS, AMPS or whatever other links you have to the vehicle this 30-second cycle.
Things are happening, but they are not as fast moving as the rest of the Internet/telco business.
All your good old GSM cell phones speaks a rather hefty AT command set. The modem manual for the R320 (early wap phone) at Ericsson's developer area is over 300 pages long. You can basically explore the phone's entire funtionality through the command set.
Connect to your phone through a terminal emulator using either the IR COM port or a serial cable and COM1. Do the AT dance.
BTW:
You can shorten your connect time for a PPP based GSM data channel from 30 to 15 seconds by using an ISDN modem. This will not improve your bandwidth, only shorten the link setup time.
Do
AT+CBST=71,0,1
before you dial your ISDN modem.
Some networks can only hook up to an ISDN modem that is set to the older V1.10 standard. Check your local manual.
The time from ATDxxx to CONNECT is usually 4 seconds. The rest of the connect time is PPP negotiation stuff.
The all dominant means of wireless internet in Europe is running a datachannel over the GSM network. Circuit switched 9600 BPS. Works *everywhere* in Europe and many other areas as well.
It has the (often unknown) feature of being able to dial an ISDN modem with very quick connect times (4 seconds from ATDxxx to CONNECT).
Stable in high speeds (up to 250 km/h alt. 156 mph). My only problem is that the circuit is lost sometimes when traveling through tunnels etc, and must be setup again.
The followup standard is GPRS (not yet deployed in the US), basically an upgrade from GSM with packet switched data.
Allows 128 kbit according to the specs, but do not expect anything above 40 kbit. Circuit switched voice and data always takes precedence in a GPRS enabled cell. This means that packed switched data will have to share whatever bandwidth is left.
CDPD (which I have played with as well) claims 19.2 kbps, which is a lie. As soon as you move or get congestion you are lucky if you can pack 4 kbps.
Also note the problems that TCP/IP has with these kinds of nets. Any momentary noise on the line which is taken care of through a low (sub-IP) level resend by the radio network, will be viewed by TCP/IP as a congestion. TCP will throttle back and will take a looong time to go back to full speed.
Slashdot Mirror
http://www.gnu.org/fun/jokes/ed.msg.html
If it is free, you are not the client. You are the product, and you are being sold.
#!/bin/sh
exit 0
Has probably been in place for most unix flavors since the early seventies.
And it is *widely* used to this day.
GSM phones here operate on 850/1900Mhz. 3G is not really deployed yet.
They do that already.
/MF
All modern ECUs have a "limp home" mode activated if they lose one or more sensors. Basically they run a default setting on ignition and fuel injection that allows the engine to continue to operate.
If your MIL (Malfunction Indication Light) lights up on your dash, you are probably in limp home mode.
Ripping the GPS and/or phone antenna may not be enough.
1. If you are in a good AMPS coverage area, the radio will get a signal even without an antenna.
2. If there is no GPS signal available, the car is still able to temporarily track itself by measuring the wheel speed of the left and right (non-drivetrain) wheels and do dead reckoning calculation based on speed, time and direction (left/right differences == turning car). This method is only valid for a while since the errors add up over time.
Also, not all cars have this feature either.
Hmmm.
I forgot to mention that the article's description of the eavesdropping blocking the line for emergency calls points to a incorrectly designed telematics system.
What should happen is that any non-emergency call is aborted when a higher level event, such as an airbag deployment, occurs.
This frees the line for emergency use.
Have been developing systems like this for years.
A few telematics systems lets you silently call upp the vehicle and eavesdrop using the handsfree functionality, but most don't. Some of the protocols supports it, while the vehicle implementation of it does not.
What a call center operator can always do, however, is silently track your car. It usually works by calling up the vehicle over Verizon's WIN4 net, transmit authentication codes and a request to track the car's progress. Every five-fifteen minutes thereafter, the car will call up and transmit a GPS log to the call center.
Remote door unlock is often also a trivial matter.
No, you cannot call up and hijack the vehicle from the ordinary phone network since all WIN4 subscriptions have an areacode of 500, rending them unreachable from any ordinary phone. Calling out to them is a long and tedious process. On top of this, every vehicle usually have a unique passcode generated when the car is built. A list of these passcodes are then sent directly to the call center who uses them to access the cars.
No, you cannot reprogram the 800 number dialled by the vehicle in case of a crash or other event. The number is setup in the WIN4 network. No matter what number you are trying to get to from the handset, you will end up at the same DNIS.
My $.05
I work with Telematics as a software systems architect.
The main problems we encounter are:
Coverage.
Only AMPS can provide any kind of decent coverage in the states. This means 1200 BPS and heavy error correction. We use everything from DTMF tones to stripped down V.27 (fax) data bursts to get the message across. No. Sattelites are too expensive.
Driver attention.
If you are driving a vehicle, you should not play around with an interface. There are also regulations on what you can put on the dashboard when it comes to screens etc. Services has to be kept extremely simple. We are just learning to do voice recognition in an automtive environment with noise, radio, screaming kids etc.
Tech cycles.
A car is supported for approx. 10 years by its manufacturer. Which mobile standard should we use, given that GSM, GPRS, or CDMA gets the right coverage? Forget 802.11 where the vehicles act as nodes in a network. 802.11 only works up to 20 km/h
Conservatism.
The automotive industry have change cycles measured in years, if not decades. It's very hard to match up the mentality of that industry with the dynamic and unstable nature of the computer and wireless business.
Today everyone are aiming at deploying boring, basic services such as theft notification with vehicle tracking, roadside assistance, remote door unlock, crash notification etc. BMW in Europe is probably the leader where the roadside assistance call center can update a map with routes that is displayed in the new 700 series. All European solutions, BTW, uses GSM and SMS messages to transmit data. Its store and forward makes it ideal for low bandwidth mobile communication.
Next generation of services will include traffic, food, gas, service info and geo-ads. Cool things like streaming video is faaar down the road.
When we are playing around in the lab, we look at the possibility of using USB keys as storage (MP3 etc) and ignition keys.
We are also looking into the possibilities of using max-bandwidth/least-cost routing that switches between different technologies depending on what coverage you currently have. You would then have a fixed IP-address that acts as a proxy and forwards packets to the vehicle using CDPD, SMS, AMPS or whatever other links you have to the vehicle this 30-second cycle.
Things are happening, but they are not as fast moving as the rest of the Internet/telco business.
All your good old GSM cell phones speaks a rather hefty AT command set. The modem manual for the R320 (early wap phone) at Ericsson's developer area is over 300 pages long. You can basically explore the phone's entire funtionality through the command set.
Connect to your phone through a terminal emulator using either the IR COM port or a serial cable and COM1. Do the AT dance.
BTW:
You can shorten your connect time for a PPP based GSM data channel from 30 to 15 seconds by using an ISDN modem. This will not improve your bandwidth, only shorten the link setup time.
Do
AT+CBST=71,0,1
before you dial your ISDN modem.
Some networks can only hook up to an ISDN modem that is set to the older V1.10 standard. Check your local manual.
The time from ATDxxx to CONNECT is usually 4 seconds. The rest of the connect time is PPP negotiation stuff.
For what it's worth.
Sorry, no point, just rambling.
Ping time 500msec?
The all dominant means of wireless internet in Europe is running a datachannel over the GSM network. Circuit switched 9600 BPS. Works *everywhere* in Europe and many other areas as well.
.05.
It has the (often unknown) feature of being able to dial an ISDN modem with very quick connect times (4 seconds from ATDxxx to CONNECT).
Stable in high speeds (up to 250 km/h alt. 156 mph). My only problem is that the circuit is lost sometimes when traveling through tunnels etc, and must be setup again.
The followup standard is GPRS (not yet deployed in the US), basically an upgrade from GSM with packet switched data.
Allows 128 kbit according to the specs, but do not expect anything above 40 kbit. Circuit switched voice and data always takes precedence in a GPRS enabled cell. This means that packed switched data will have to share whatever bandwidth is left.
CDPD (which I have played with as well) claims 19.2 kbps, which is a lie. As soon as you move or get congestion you are lucky if you can pack 4 kbps.
Also note the problems that TCP/IP has with these kinds of nets. Any momentary noise on the line which is taken care of through a low (sub-IP) level resend by the radio network, will be viewed by TCP/IP as a congestion. TCP will throttle back and will take a looong time to go back to full speed.
My