On 24/09/10 21:03, tony sayer wrote:

I thought that GSM was well encrypted as it was?..

I think you should assume that most of the crypto in GSM has been broken
to a greater or lesser degree. Remember that:

(1) GSM is really quite old now, and

(2) there were political reasons to limit the strength of the crypto

I'm pretty sure that real time cryptanalysis of an GSM call was
demonstrated at one of the hacker conferences quite a number of years ago.

-roy

"tony sayer" wrote in message
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scribeth thus
"Rupert Moss-Eccardt" wrote in message
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Steve Terry wrote:
"Rupert wrote in message
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Steve Terry wrote:
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In , Steve Terry
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On 22 Sep, 11:55, wrote:
"Roy wrote in message



On 22/09/10 11:24, Recliner wrote:
snip

Tetra is a badly conceived and applied standard that should never have
existed and only does because of the vast amounts of money and
bureaucracy dedicated to it.

But quite why?..


Clearly Politics, the Home Office wanted a system that was entirely
independent of publicly available networks.
No matter how badly conceived or developed, with no limit on cost.
With whatever the disadvantage to the public, or even creating unknown
health issues.
(What **** thought it a good idea to multiplex Tetra at only 17.6Hz?!
a frequency known to cause visual epilepsy )

Not having a entirely independent system not being something that
worried the Scandinavians meant they got a very practical digital system,
(900MHz GSM Pro) years earlier for about one hundredth the price of Tetra.

GSM Pro of course offers closed secure PTT groups and normal
international phone calls, to all emergency services and commercial users.

In the USA PTT over cellular is fast becoming popular for closed
commercial and emergency services groups.
http://en.wikipedia.org/wiki/Push_to_talk
(Maybe cos Tetra with its vested interests doesn't exist there?)

Only Orange offered a hardly advertised PTT over GSM here,
and that was only to business users, such limited offering was
destined to fail.

Why almost non existent offerings from the UK GSM networks?
IMHO it must have been Gov pressure not to affect Tetra
and Dolphin sales and the vast army of bureaucrats it supports

Steve Terry
--
"I would like to plead for my right to investigate natural phenomena
without having guns pointed at me.
I also ask for the right to be wrong without being hanged for it."
- Wilhelm Reich, November 1947

"Roy Badami" wrote in message
...
On 24/09/10 21:03, tony sayer wrote:

I thought that GSM was well encrypted as it was?..

I think you should assume that most of the crypto in GSM has been broken
to a greater or lesser degree. Remember that:

(1) GSM is really quite old now, and

(2) there were political reasons to limit the strength of the crypto

I'm pretty sure that real time cryptanalysis of an GSM call was
demonstrated at one of the hacker conferences quite a number of years ago.
-roy

Maybe that's why extra levels of encryption are available for GSM Pro
handsets

Although if you are going to go to all that trouble to crack police comms
you might as well just bug your police station and cars.

Steve Terry
--
"I would like to plead for my right to investigate natural phenomena
without having guns pointed at me.
I also ask for the right to be wrong without being hanged for it."
- Wilhelm Reich, November 1947

"tony sayer" wrote in message
...
In article , Steve Terry
scribeth thus
"Rupert Moss-Eccardt" wrote in message
...
Steve Terry wrote:
"tony wrote in message
...
In , Steve Terry
scribeth thus
"Roy wrote in message
...
On 22 Sep, 11:55, wrote:
"Roy wrote in message



On 22/09/10 11:24, Recliner wrote:
snip
Trower report:
http://www.tetrawatch.net/papers/trower_report.pdf

Some really good science there eh;?....
snip

Yes it's very suspect science, but there is little doubt that unnecessarily
multiplexing at 17.6Hz could have been a completely avoidable health risk

In 2000 whist visiting Sweden i spoke to police officers about
their new GSM Pro personal radios (at the time using waterproof
Ericsson R250s) and they were very satisfied with them.
(retail price for Ericsson R250s at the time was around £100 each)
http://www.gsmarena.com/ericsson_r250s_pro-119.php

These 450 MHz versions?. With PPT I presume?..


900MHz on existing public GSM networks with high priority GSM Pro sims
With closed group PTT

Also if required additional encryption can be added to each phone.

I thought that GSM was well encrypted as it was?..

Debatable


We of course years later had to reinvent the wheel, at the cost of
billions
to the public for the benefit of private companies, and to the detriment
of the public allowing them to share an improved GSM network.

Are you suggesting that the public shared a security network?..
Tony Sayer


Why not, it works for them, and if you think about it, most UK police
personal comms has for years already been over officers personal
GSM phones on the public network, especially still in Tetra poor
signal black spot areas.

The added advantage to Scandinavian public, is that areas where
emergency services have poor GSM signal get priority for additional
cells to strengthen the existing network, so everyone wins.

In the early days of Tetra if it wasn't for officers being able to
fall back on their GSM phones, Tetra's many black spot areas,
would have made it fail.

Also some UK police services have been using Blackberrys over
public GSM networks for collating data.
No one has questioned any security issues about police using the
public networks

The one thing that has worried me about officers unbridled use of
GSM phones is that where their PRs calls are recorded for
evidential later use, of course their phones aren't.

Steve Terry
--
"I would like to plead for my right to investigate natural phenomena
without having guns pointed at me.
I also ask for the right to be wrong without being hanged for it."
- Wilhelm Reich, November 1947

On 22/09/2010 11:24, Recliner wrote:
Bad news -- it looks like mobile phones may work on the Tube after all,
according to that ever accurate source, the Evening Standard. So no more
cutting off of noisy phone callers as the train enters the tunnel.

There are parts of the Tube, normally near ventilation shafts, where you
can get a clear line of sight and thus a respectable signal.

I believe that Arsenal is one of them.

On 24/09/2010 00:40, Steve Terry wrote:

GSM could, GSM is now possible on airliners using cells on the aircraft
linked up to satellite or down to ground stations, and GSM is regularly
used on sea going Ferries using similar systems.

I understand that Ryanair is getting ready to use GSM on its aircraft soon.

AIUI, ferries to France and Spain out of Portsmouth have them I doubt
that they are necessary on Dover-Calais, considering that one's mobile
can already start picking up French signals on the English side.

On 22/09/2010 20:33, Neil Williams wrote:
On Wed, 22 Sep 2010 11:24:29 +0100, "Recliner"
wrote:

It would mean Tube passengers could stay in mobile range throughout
their journey, a move which could boost the capital's economy, although
there would almost certainly be some quiet carriages on Underground
trains where phones were banned.

Even better idea - how about making it data-only? Texting and use of
the Internet is not disruptive. Phone calls on a crowded Tube train
would be unpleasant.

Same with planes, really.

Neil
Isn't that the plan on aeroplanes, however? No voice, only text messages.

Steve Terry wrote:
"tony wrote in message
...
In , Steve Terry
scribeth thus
"Rupert wrote in message
...
Steve Terry wrote:
"Rupert wrote in message
...
Steve Terry wrote:
"tony wrote in message
...
In , Steve Terry
scribeth thus
"Roy wrote in message
...
On 22 Sep, 11:55, wrote:
"Roy wrote in message



On 22/09/10 11:24, Recliner wrote:
snip

Tetra is a badly conceived and applied standard that should never have
existed and only does because of the vast amounts of money and
bureaucracy dedicated to it.

But quite why?..


Clearly Politics, the Home Office wanted a system that was entirely
independent of publicly available networks.
No matter how badly conceived or developed, with no limit on cost.
With whatever the disadvantage to the public, or even creating unknown
health issues.
(What **** thought it a good idea to multiplex Tetra at only 17.6Hz?!
a frequency known to cause visual epilepsy )

Your first incorrect assumption was that the Home Office had any real
input into Tetra. Wrong department. Try again.

Not having a entirely independent system not being something that
worried the Scandinavians meant they got a very practical digital system,
(900MHz GSM Pro) years earlier for about one hundredth the price of Tetra.

When do you think GSM Pro became a "standard". When do you think Tetra did?

GSM Pro of course offers closed secure PTT groups and normal
international phone calls, to all emergency services and commercial users.

In the USA PTT over cellular is fast becoming popular for closed
commercial and emergency services groups.
http://en.wikipedia.org/wiki/Push_to_talk
(Maybe cos Tetra with its vested interests doesn't exist there?)

There are still issues. Perhaps you should read stuff around the DHS
problems with there not being a single standard for all agencies.

Only Orange offered a hardly advertised PTT over GSM here,
and that was only to business users, such limited offering was
destined to fail.

Why almost non existent offerings from the UK GSM networks?
IMHO it must have been Gov pressure not to affect Tetra
and Dolphin sales and the vast army of bureaucrats it supports


The PTT over GSM has well-known shortcomings. Call setup time is too
long, talk groups are too small. But please don't let facts get in the
way of a good rant.

Rather than parading your ignorance repeatedly, why not look some stuff
up and make a reasoned argument?

Roy Badami wrote:
On 24/09/10 21:03, tony sayer wrote:

I thought that GSM was well encrypted as it was?..

I think you should assume that most of the crypto in GSM has been broken
to a greater or lesser degree. Remember that:

(1) GSM is really quite old now, and

(2) there were political reasons to limit the strength of the crypto

I'm pretty sure that real time cryptanalysis of an GSM call was
demonstrated at one of the hacker conferences quite a number of years ago.

More importantly there have been off-the-shelf devices available from a
number of suppliers for many years that, even in 2003 were only about £50k.

And, of course, back haul is also vulnerable.

Steve Terry wrote:
[SNIP]


We of course years later had to reinvent the wheel, at the cost of
billions
to the public for the benefit of private companies, and to the detriment
of the public allowing them to share an improved GSM network.

Are you suggesting that the public shared a security network?..
Tony Sayer


Why not, it works for them, and if you think about it, most UK police
personal comms has for years already been over officers personal
GSM phones on the public network, especially still in Tetra poor
signal black spot areas.

You are missing the point about Tetra that you can use it in DMO mode
anywhere, which is of major benefit for the other emergency services and
can use terminals to backhaul to your PSTN gateway if you wanted to.

In the early days of Tetra if it wasn't for officers being able to
fall back on their GSM phones, Tetra's many black spot areas,
would have made it fail.

Quite the opposite for the user groups I'm most familiar with.

Also some UK police services have been using Blackberrys over
public GSM networks for collating data.
No one has questioned any security issues about police using the
public networks

Yes, they have. For what might be termed 'retail' policing, Blackberrys
(with the encryption they provide, which has been in the news recently)
are approved. For some other applications, BBs are not approved.

The one thing that has worried me about officers unbridled use of
GSM phones is that where their PRs calls are recorded for
evidential later use, of course their phones aren't.

There are solutions offered by some MNOs that do record the calls even
on GSM.