Re: [TSCM-L] Fwd: [ISN] Why VOIP Needs Crypto

From: j <j..._at_2ndr.com>
Date: Fri, 07 Apr 2006 10:54:08 -0400

Just two comments on an already well informed
post.

There is a fifth way to listen to a telephone which
is inductive coupling. This is non-invasive and allows
access at any point on the line by the application of
a coil, like an amp-probe, around the wire.

A sixth way is to wire the telephone with a simple
circuit which modulates the telephone signal onto
the house power wiring. Then anyone on the same
power circuit can listen to the conversation.

Modern telephone switches are computerized and
digital. The phone can be paired to another telephone
virtually anywhere in the world. The second phone
behaves in parallel to the source phone in that
it is simply a listen-only or full duplex extension.
When law enforcement or some criminal enterprise
has access to this technology it is impossible to
detect. Criminal enterprise can be cleared from the
line by calling the service department and reporting
"trouble on the line" at which time they will look
at the phone configuration. The phone company, aware
of this activity, can put a monitor on the phone record for
some period. (I think they did it for me for 3 or 6 months).
They will also start looking into who modified the
the record. Since so few people understand this they
rarely if ever complain, so they rouge switch administrator
usually has free rein.

Obviously this post covers only phones with physical
conductors. The wireless phones are susceptible to
interception and this is "grey area legal".

As far as computers are concerned it is a little known
fact that by a hole in Internet legislation the ISP
routinely records and archives the Internet activity
of its customers. Law enforcement cannot use
this information as evidence in criminal prosecutions
but they can use it to be informed of any illegal activity.
This is not a real problem since your customers
should not be criminals. But, rouge administrators
working for competitors, attorneys, or powerful enemies,
can use the information to survey all of your activity and
connections and to interfere with those.

They can also use the information that is not illegal
but embarrassing to extort or slander. The protection
against this is simple - be prepared for your private
activities to be exposed in divorce court or some
other public way and be prepared to care not..

A rule of thumb about any computer network
administrator - they are all rouge. Detection
is almost impossible even if you understand it, and
the money is too good.

>> There are basically four ways to eavesdrop on a telephone call.
>>
>> One, you can listen in on another phone extension. This is the method
>> preferred by siblings everywhere. If you have the right access, it's
>> the easiest. While it doesn't work for cell phones, cordless phones
>> are vulnerable to a variant of this attack: A radio receiver set to
>> the right frequency can act as another extension.
>>
>> Two, you can attach some eavesdropping equipment to the wire with a
>> pair of alligator clips. It takes some expertise, but you can do it
>> anywhere along the phone line's path -- even outside the home. This
>> used to be the way the police eavesdropped on your phone line. These
>> days it's probably most often used by criminals. This method doesn't
>> work for cell phones, either.
>>
>> Three, you can eavesdrop at the telephone switch. Modern phone
>> equipment includes the ability for someone to listen in this way.
>> Currently, this is the preferred police method. It works for both land
>> lines and cell phones. You need the right access, but if you can get
>> it, this is probably the most comfortable way to eavesdrop on a
>> particular person.
>>
>> Four, you can tap the main trunk lines, eavesdrop on the microwave or
>> satellite phone links, etc. It's hard to eavesdrop on one particular
>> person this way, but it's easy to listen in on a large chunk of
>> telephone calls. This is the sort of big-budget surveillance that
>> organizations like the National Security Agency do best. They've even
>> been known to use submarines to tap undersea phone cables.
>>
Received on Sat Mar 02 2024 - 00:57:19 CST