Page 418 - Handbook of Modern Telecommunications

Network Management and Administration 3-209

Telecommunications
Service Provider Network
5ESS Switch

Service Provider
Administration-Access Access
Service Provider Access-
Administration Service Provider Delivery

Delivery Delivery- Collection
Administration-Delivery
Collection
Law Enforcement
Administration-Collection
Law Enforcement
Administration

FIGu RE 3.8.4 CALEA reference model.

• Delivery Function (DF)
• Database of target and warrant information
• Provisioning interface
• Proprietary interfaces to AFs
• Standards based (J-STD-025, ETSI, TIIT, PacketCable) delivery of intercepted traffic to CFs
• Runs on off the shelf UNIX based platforms and programmable switch machines
• Collection Function (CF)
• Collects and records lawfully authorized intercepted communications (e.g., call content) and call-
identifying information for law enforcement agencies

Figure 3.8.5 shows from another perspective the principal functions and interfaces of the lawful
intercept architecture.

3.8.6.2 ETSI Reference Model for the European Community
The European Telecommunications Standard Institute (ETSI) definition of lawful interception is the
following: Interception is an action based on the law, performed by a network operator or access pro-
vider or service provider (NOW/AP/SVP, the term telecommunications service provider is preferred by
the authors in this book), of making available certain information and providing that information to a
law enforcement monitoring facility.
Figure 3.8.6 shows the basic flow of information exchange between service providers and LEAs.

3.8.6.2.1 Basics of This Standard
The chosen solution to the requirements of the LEAs is a three-ported interface. Such an interface struc-
ture is shown in Figure 3.8.7.
The first HI port shall transport various kinds of administrative information from/to LEA and NOW/
AP/SVP. There shall be a complete separation between the administrative interface (HI1) and the techni-
cal interfaces (HI2 and HI3) of the NOW/AP/SVP, in order not to give the Law Enforcement Monitoring
Facility (LEMF) the possibility to establish or modify an interception without an action of a mandated
agent of the NOW/AP/SVP. In case of a nonautomatic administrative interaction, this interface may also
be manual rather than electronic.