Page 423 - Handbook of Modern Telecommunications

3-214 CRC Handbook of Modern Telecommunications, Second Edition

• There should be physical and logical access controls.
• Any necessary key, passwords, and user identifications for the authorization and the logical access
to the interception function should be securely stored.
• Any transmission of passwords and user identifications for access to interception functions
should be secure.
• Physical interfaces should be secured mechanically and/or logically against unauthorized use.
Transmission of all information between the NOW/AP/SVP and the LEMF across HI1, HI2, and
HI3 shall be confidential. During communication between systems that are not based on leased lines,
appropriate mechanisms should ensure that the recipient is in the position to verify or authenticate the
identity of the sender while the connection is set up. During communication between systems that are
not based on leased lines, appropriate mechanisms should ensure that the sender is in the position to
verify or authenticate the identity of the recipient at the start of a connection.
Only specifically authorized personnel should be able to control interceptions. In general, the LEA
should not have any direct access to any network element.
The entire communication between the administration system and the interception function should
be confidential. All internal interfaces must be secured.
The interception functions shall be implemented in such a manner that:
• The interception subject and his correspondents do not know that a lawful interception is
active.
• During the intercepted communication itself, the quality of the communication shall remain the
same as usual and the service shall be unchanged, including all supplementary services such as
call forwarding, etc.
• When there is no intercepted communication, the quality of communication shall remain the
same and the service shall be unchanged; in other words, there is no modification to services sup-
plied or information received either by the interception subject or by some other party.
An employee of NWO/AP/SVP who has been duly authorized may be permitted to know that inter-
ception is in progress, or that a subscriber is an interception target. But an employee of NWO/AP/SVP
who has not been duly authorized may not be permitted to know that interception is in progress, or that
a subscriber is an interception target.

3.8.7 Principles of Monitoring and Intercepts
(Hardware and Software Probes)
State-of-the-art technology permits monitoring of everything in networking infrastructures. But every-
thing has a price tag. The following challenges must be addressed by telecommunications service pro-
viders and LEAs:
• How to identify dynamic targets
• How to deal with roaming in/out subscribers
• How to intercept compressed and encrypted traffic
• How to capture a call in progress
• How to meet real time constraints
• How to deal with identity management
• How to identify target locations
• How to identify prepaid targets
Lawful intercepts require full monitoring capabilities in networks. This requirement causes several
concerns on behalf of the telecommunications service providers:
• Optimizing the combination of internal and external lawful intercept capabilities