CALEA AND NEXT-GENERATION NETWORKS
A discussion of the U.S. Communications Assistance for Law Enforcement Act (CALEA) and its implications for the design of next-generation networks
A MetaSwitch™ White Paper
CALEA and Next-Generation Networks: A MetaSwitch White Paper
EXECUTIVE SUMMARY
Enacted by Congress in 1994, the U.S. Communications Assistance for Law Enforcement Act (CALEA) requires telecommunications carriers to ensure that law enforcement agencies (LEAs) can continue to undertake lawfully authorized electronic surveillance in the face of rapid technological change. CALEA compliance imposes additional requirements on next-generation voice networks. Since the law’s enactment, industry groups have worked with the Federal Communications Commission, the U.S. Department of Justice and the FBI to develop standards for meeting these requirements. These standards specify handover interfaces that enable the interception of the voice streams (or "call content") and the delivery of calling/called numbers (or "call data") to the LEAs. This white paper discusses CALEA’s legislative and regulatory environment, explores the Act’s implications for next-generation network architecture and offers a model for CALEA-compliant, next-generation network design. It further discusses the capabilities of MetaSwitch’s VP3500 Next Generation Class 5 Switch, and discusses how the VP3500 enables carriers to meet CALEA requirements as they migrate their networks to broadband voice service.
NOTICE
Copyright © 2003 MetaSwitch, a division of Data Connection. This white paper is provided for informational purposes only. MetaSwitch and Data Connection make no warranties, express or implied, as to the accuracy of the content. MetaSwitch and Data Connection are registered trademarks of Data Connection Limited and Data Connection Corporation. All other brand and product names are trademarks or registered trademarks of their respective owners.
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CONTENTS
1. ................................................................................................. ................................................................ BACKGROUND ................................................................................................. 1
1.1 1.2 1.3 U.S. LAW AND REGULATION....................................................................................... 1 CALEA’S SAFE HARBOR PROVISION AND INDUSTRY STANDARDS........................ 1 ELECTRONIC SURVEILLANCE ENVIRONMENT OUTSIDE THE U.S......................... 2
2.
HANDOVER INTERFACES ......................................... CALEA COMPLIANCE: HANDOVER INTERFACES ......................................... 4
2.1 2.2 CALL IDENTIFICATION ............................................................................................... 4 CALL CONTENT INTERCEPTION ............................................................................... 4
3.
NEXT-GENERATION ............................................. CALEA AND NEXT-GENERATION NETWORKS ............................................. 5
3.1 3.2 3.2.1 3.3 CALEA COMPLIANCE REQUIREMENTS ..................................................................... 5 CALEA MANAGEMENT INTERFACE REQUIREMENTS ............................................. 5 PROVISIONING INTERFACE ........................................................................................ 5 DESIGNING NEXT-GENERATION NETWORKS FOR CALEA COMPLIANCE ........... 6
4.
............................................ CALEA SUPPORT IN THE METASWITCH VP3500 ............................................ 8
4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 METASWITCH VP3500 OVERVIEW .............................................................................. 8 METASWITCH VP3500 APPLICATIONS........................................................................ 9 VP3500 CALEA DESIGN OVERVIEW ............................................................................. 9 THE METASWITCH ARCHITECTURE FOR CALEA ...................................................10 INTERFACE OVERVIEW ..............................................................................................11 PROVISIONING OVERVIEW ........................................................................................11 INTERCEPTION OF CALL ASSOCIATED INFORMATION ........................................11 INTERCEPTION OF CALL CONTENT ........................................................................12 NETWORK TOPOLOGIES ............................................................................................13 ADDITIONAL REQUIREMENTS ..................................................................................14
5. 6. 7.
.................................................................................................. ..................................................................15 CONCLUSION .................................................................................................. 15 CONNECTION.................................................... ONNECTION....................................................16 METASWITCH AND DATA CONNECTION.................................................... 16 USED ...........................................................................17 ........................................... GLOSSARY OF TERMS USED ........................................................................... 17
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1. BACKGROUND
1.1 U.S. LAW AND REGULATION
In 1994, the U.S. Congress enacted the Communications Assistance for Law Enforcement Act (CALEA) to preserve the ability of law enforcement agencies (LEAs) to undertake electronic surveillance, commonly known as wiretapping, in the face of rapid technological change. Under Section 103 of CALEA, U.S. telecommunications carriers must ensure that their equipment, facilities or services can, pursuant to a court order or other lawful authorization: • • • • Expeditiously isolate and enable law enforcement agencies (LEAs) to intercept all wire and electronic communications. Provide LEA access to call-identifying information that is reasonably available to the carrier. Deliver intercepted communications and call-identifying information to a LEA in an acceptable form and at a remote location. Protect the privacy and security of communications and call-identifying information not authorized to be intercepted.
Congress did not specify how carriers should meet these four LEA assistance-capability requirements, leaving it up to the Federal Communications Commission (FCC) to write specific rules governing CALEA. The assistance capabilities specified by the Act were supposed to be implemented by Oct. 25, 1998, but the FCC delayed the deadline to June 30, 2000. Carriers that are unable to provide the required capabilities may petition the FCC for an extension, or for a determination that compliance is not reasonably achievable. The FBI has published a Flexible Deployment Assistance Guide (see http://www.askcalea.com/flexd.html) to help carriers deploy CALEA-compliant solutions in accordance with their normal upgrade cycles, where such timing will not delay implementation of CALEA solutions in areas of high priority to law enforcement. However, any carrier implementing a next-generation network will have to consider the implications of CALEA and deploy a CALEA-compliant solution. 1.2 CALEA’S SAFE HARBOR PROVISION AND INDUSTRY STANDARDS
Section 107(a) of CALEA provides a “safe harbor” for telecommunications firms, stating that carriers and manufacturers will be deemed CALEA-compliant if they meet publicly available standards adopted by either the industry or the FCC. Under CALEA, the FCC may establish technical requirements or standards if industry associations or standardsetting organizations fail to issue them, or if a government agency or any other party submits a petition to the FCC stating that industry-set requirements or standards are insufficient.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
In 1997, the TIA and Committee T1 developed an initial standard, J-STD-025, to satisfy CALEA’s safe harbor provision. The Department of Justice (DOJ) and the FBI responded that the industry’s standard was insufficiently inclusive. In 2002, following much debate and litigation, the FCC mandated that the industry add six of nine items on a DOJ/FBI “punch list” to its standards by June 30, 2002. The TIA and Committee T1 updated the standard, published as J-STD-025A. The Committee is currently working on a further revision, J-STD-025B, covering packet-voice networks. Other industry standards bodies have also developed electronic surveillance specifications for their respective industry segments: • • CableLabs has published PacketCable Electronic Surveillance Specification PKT-SP-ESP-101-991229. The 3rd Generation Partnership Project (3GPP) has developed standards for lawful interception architecture and functions, 3GPP TS 33.107 V5.5.0 (2002-12), and handover interface for lawful interception, 3GPP TS 33.108 V6.0.0 (2002-12). The Society of Cable Telecommunications Engineers (SCTE) has published IPCablecom Electronic Surveillance Standard ANSI/SCTE 24-13 2001. This is essentially the same document as the CableLabs specification. ELECTRONIC SURVEILLANCE ENVIRONMENT OUTSIDE THE U.S.
•
1.3
Laws similar to CALEA are being implemented in Canada and Europe. However, some countries, such as Mexico, explicitly forbid electronic surveillance. Countries that are implementing electronic surveillance laws are generally following either the U.S. or European regulations. In Europe, both the European Union (EU) and national governments regulate electronic surveillance. The EU issues council directives, which member governments are required to implement. The European Telecommunications Standards Institute (ETSI) Security Techniques Advisory Group has detailed the legislative and regulatory environment in Europe in a technical report, ETR 330. ETSI has produced some standards that describe how to meet the EU’s Lawful Intercept resolutions: • ETSI - ETR 331 ed. 1 (1996-12) Definition of user requirements for lawful interception of telecommunications; Requirements of the law enforcement agencies, December 1996. This provides more detail than the EU Council Resolution. ETSI - ES 201 158 V1.2.1 (2002-04) Telecommunications security; Lawful Interception (LI); Requirements for network functions, April 2002. This defines a set of interfaces (handover interface HI) between the network provider and the law enforcement Monitoring Facility (LEMF).
•
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
• ETSI - ES 201 671 V2.1.1 (2001-09) Telecommunications security; Lawful Interception (LI); Handover interface for the lawful interception of telecommunications traffic, September, 2001. This provides standards for the interfaces between the network provider and the LEMF.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
2. CALEA COMPLIANCE: HANDOVER INTERFACES
2.1 CALL IDENTIFICATION
Carriers identify calls for interception by collecting information such as called and callingparty number, time of day, length of call and post-dial digits. Carriers format this information according to the appropriate handover interface specification (J-STD-025A, for example, specifies an ASN.1 encoding), and transport it to the LEA using an encrypted packet network, typically IP or X.25, referred to as the Call Data Channel (CDC). 2.2 CALL CONTENT INTERCEPTION
To intercept call content, carriers must duplicate the voice streams making up a call and deliver them to the LEA, either over a combined channel carrying both the call’s transmit and receive paths, or by using separate channels for the transmit and receive paths, referred to as the Call Content Channel (CCC). TDM-based networks typically achieve this by using dedicated T1 links, or by routing calls across the PSTN to the LEA. Carriers deliver packet-voice data by using some form of packet-based network connection, such as IP.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
3. CALEA AND NEXT-GENERATION NETWORKS
3.1 CALEA COMPLIANCE REQUIREMENTS
CALEA compliance imposes additional requirements on next-generation networks: • Suspects must not detect interception, requiring the intercept to occur within the carrier’s network, and not at a customer’s premises. In addition, the intercept must not be detectable by any change in timing, feature availability or operation. If a suspect is subject to interception by more than one agency, networks must be able to handle separate intercepts of different kinds, for various agencies that may not be aware of each other’s intercepts. Any telecommunications carrier that originates or terminates calls is responsible for providing lawful interception. This includes support for lawful interception of SIP peer-to-peer calls, even where these do not transfer to the wider PSTN. CALEA MANAGEMENT INTERFACE REQUIREMENTS
•
•
3.2
CALEA imposes the following management requirements on carriers: • • • The carrier needs to provide call content information (CCC). The carrier needs to provide call associated data (CDC) (Call-identifying information in J-STD-025A terminology). The carrier needs to provide a provisioning interface to control interception.
3.2.1 PROVISIONING INTERFACE
The provisioning interfaces to control interception must support the following requirements:
• • •
The interface must only be accessible to authorized CALEA users. It must support validating and inputting an input warrant request from an LEA. No information about warrants in place can be available to unauthorized users, including logging and tracing facilities.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
3.3 DESIGNING NEXT-GENERATION NETWORKS FOR CALEA COMPLIANCE To date, there is no complete standard handover interface for packet-based, nextgeneration networks. However, interfaces that identify subscribers by using directory numbers, as defined in J-STD-025A, can support electronic surveillance. This approach works well for Voice over Internet Protocol (VoIP) networks that interface to the existing PSTN and assign each subscriber a fixed directory number, and it fits seamlessly with existing mechanisms that administer electronic surveillance based on directory numbers. However, it does not work with SIP networks based on addressing that uses SIP Uniform Resource Identifiers (URIs).
Figure 1.
Next-generation VoIP Architecture
Figure 1 shows an example of a next-generation VoIP architecture with electronic surveillance capabilities for “on-net” calls, using the approach defined in J-STD-025A. This architecture employs call agents, access gateways and trunking gateways. The call agent is responsible for all call control and terminating the signaling from subscriber gateways and the PSTN, but it does not directly see Real-time Transport Protocol (RTP) voice streams. Nevertheless, the call agent can manage intercepts when required, as follows: • Call-identifying information − The call agent already has the data needed, by virtue of being on the signaling path. It simply formats this data for delivery over the call data channel (CDC) to the LEA.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
• Call-content interception − The carrier must be able to intercept calls without subscriber detection, whether the calls remain within the carrier’s IP network or access another network (e.g. PSTN). The call agent achieves transparent call-content interception by routing the call via a device that can duplicate the call’s content and send it to the LEA using the call content channel (CCC). As shown in Figure 1, an access gateway performs this task, routing the duplicated call content to the LEA across the PSTN via a trunking gateway. Alternatively, packet duplication can be achieved using an edge router in the carrier network, but this function is not yet available in most edge routers because they are not yet “voice-aware”. If the CALEA configuration requires “Separated” CCCs, then this is done by using a pair of circuits (DS0s), one for the receive path and one for the transmit path. If the configuration specified “Combined”, this is done by using a single circuit (DS0) over which both receive path and transmit path content is transmitted. Multiple intercepts − If more than one LEA places an intercept on a subscriber, the call agent can deliver call-identifying information and call content over the CDC or CCC channels, respectively, independently to each LEA.
•
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
4. CALEA SUPPORT IN THE METASWITCH VP3500
4.1 METASWITCH VP3500 OVERVIEW
The MetaSwitch VP3500 Next Generation Class 5 Switch combines traditional Class 5 capabilities such as 80+ CLASS/Centrex features and support for POTS lines with advanced ATM and IP broadband voice capabilities and enhanced subscriber services. For next generation service providers looking for a competitive edge, the MetaSwitch VP3500 opens up a host of new opportunities to reduce expenses and generate new business. • Legacy POTS subscribers can be supported by a compact, low-power chassis that is easy to deploy and manage. For carriers migrating from an existing Class 5, signaling links can be shared between the old and new switch, enabling a steady, seamless migration. The VP3500 unlocks the potential of carriers' broadband networks, whether ATM or IP based, by delivering broadband voice services natively from the switch. With no additional voice gateway, the network is simplified and unnecessary packet-TDM conversions are removed, improving voice quality. Existing legacy POTS subscribers can continue to be serviced from the same switch. The VP3500 reduces operator/support costs with a Web-based self-care option that enables both legacy POTS and broadband voice subscribers to easily view and control their own service profile. With new calling features and advanced VoIP services, the VP3500 creates new markets and revenue opportunities. And since these services can be delivered from the same switch as traditional POTS lines, deployment is easy and the network architecture is simplified. As the industry moves toward a next generation network model, MetaSwitch customers are at the forefront of the revolution, thanks to the VP3500's support for TDM, cell and packet interfaces, and its open, softswitch design which conforms to the Multiservice Switching Forum and International Softswitch Consortium reference architectures.
•
•
•
•
While a number of vendors claim to be providing Class 5 "replacements", many of these products are simply TDM-based switches with a smaller form factor than existing legacy switches. MetaSwitch's Voice-over-Broadband support, coupled with innovative IP Centrex and Web self-care services, makes for a genuine next generation solution that enables service providers to increase revenues, reduce costs and build for future growth.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
4.2 METASWITCH VP3500 APPLICATIONS
The VP3500's combination of VoIP, VoATM and TDM support enables deployment in a wide range of network configurations and applications. The following scenarios are given as examples to illustrate some of these possibilities. • • • • In a pure-TDM environment, the VP3500 can deliver POTS lines to replace or augment a traditional Class 5 switch that is running out of capacity or reaching end of life. Using the VP3500's ATM voice capabilities, service providers can leverage their investment in DSL networks by delivering voice services alongside data. The VP3500's IP capabilities enable delivery of voice services over a wide variety of broadband access networks, including fixed wireless and cable (hybrid fiber coax). Using the VP3500's broadband voice capabilities over T1, service providers can deliver traditional T1 interfaces to the customer's network, with increased (and more flexible and profitable) voice and data capacity compared with traditional TDM T1s. CLECs looking to move away from UNE-P services, or ISPs looking to offer voice services for the first time, can use the VP3500 to implement a facilities-based strategy for delivering voice services. Service providers looking to increase revenue per subscriber look to the VP3500 as a platform for advanced revenue-generating capabilities such as IP Centrex, IP Phones, soft phones, conferencing, unified messaging, Web-based call management and Webbased subscriber self-care. Carriers seeking to reduce ISP trunking costs can use the VP3500 to offload dial-up Internet traffic from legacy switches. Service providers migrating to a fully converged softswitch-based next generation network with a distributed call agent and media / signaling gateway architecture should consider the VP3500 as a key component in their strategy. VP3500 CALEA DESIGN OVERVIEW
•
•
• •
4.3
The MetaSwitch VP3500 supports lawful intercept features using the TIA J-STD-025A protocol, including intercept of call identification information and call content information. The MetaSwitch VP3500 acts as the access point for call interception, which is performed on the VP3500 without requiring an external server. Call information is passed from the VP3500 to the appropriate agencies. Each system is capable of supporting interfaces with multiple law enforcement agencies.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
Support for TIA J-STD-025A is intended to provide U.S. service providers with “safe harbor” under the U.S. CALEA regulations, once the appropriate regulatory process is completed. Technical requirements for call interception on packet-based technologies, such as VoDSL, are currently being defined in the U.S. and other markets. In the meantime, MetaSwitch allows service providers to fulfill call interception obligations using the J-STD-025A standard. 4.4 THE METASWITCH ARCHITECTURE FOR CALEA
The CALEA solution requires the following MetaSwitch components. • •
•
A MetaSwitch VP3500. A MetaSwitch EMS Server. One or more MetaSwitch EMS Clients.
The MetaSwitch VP3500 provides the Access Function and the Delivery Function as defined in J-STD-025A. The MetaSwitch EMS Server and associated Client(s) provide the Administrative Functions. The architecture is shown in the following figure.
MetaSwitch CALEA Architecture Overview
POWER FANS
MetaSwitch VP3500
MetaSwitch EMS Server
a c
Access Function
d
Delivery Function
e
LEA Collection Function
EMS Clients
POWER FANS
MetaSwitch VP3500
Administration Function
Figure 2.
CALEA Architecture
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
4.5 INTERFACE OVERVIEW
The interface designations and terminology are in line with the definitions given in the J-STD-025A specification. • • The d interface is internal to MetaSwitch. The a and c interfaces connect the MetaSwitch VP3500 with the MetaSwitch EMS Server. The connection between the VP3500 and the EMS Server is TCP/IP. The e interface is compliant with the J-STD-025A interface specification. PROVISIONING OVERVIEW
•
4.6
The MetaSwitch EMS Server and clients provide the Service Provider Administrative Function. CALEA-authorized personnel can access the EMS Server via a resident EMS Client to activate or deactivate lawful interceptions. The user logs on to the EMS with specific CALEA privileges – i.e., logs on as a CALEA user with a secure password. Once logged on, the CALEA user can access the needed screens to input the required warrant and intercept information. Other system administrators or users do not have access to the CALEA warrants or other provisioning information, nor is any information available via logging or tracing facilities. 4.7 INTERCEPTION OF CALL ASSOCIATED INFORMATION
Call associated information (CDC) is collected by VP3500 Access Function and forwarded to the VP3500 Delivery Function (DF). The call data is collected using a call services application, the Intercept Application, which sets detection points and receives notifications of the events. This application generates messages according to the J-STD-025A specification. The Delivery Function (DF) transmits the messages to the designated LEA(s) via TCP/IP. The connection between the MetaSwitch DF and the LEA Collection Function (CF) should be implemented using a secure router. The choice of the router utilized is up to the discretion of the TSP in conjunction with the LEA requirements.
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4.8 INTERCEPTION OF CALL CONTENT
The MetaSwitch establishes a Call Content Channel with the LEA Collection Function (CF) via the PSTN for each lawful intercept. The channel can be provisioned as either separate or combined. If configured as “Separate”, the channel consists of an allocated pair of DS0s. One DS0 is the channel for the transmit content from the intercept subject and the other is the channel for the receive call content to the intercept subject. If configured as “Combined”, a single DS0 is allocated that handles both the transit and receive call content. The physical interface for the DS0 is either T1 or T3. The CCC can be allocated on a permanent basis (the channel is established as soon as the lawful intercept is configured via the EMS) or on demand (the channel is only established when there is intercept activity detected as specified in the warrant). This is a configurable option and is entered at the time the intercept is set up in the EMS. The PSTN number for the LEA CF is configured at the time the warrant information is entered in the EMS by the CALEA user.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
4.9 NETWORK TOPOLOGIES
A general network configuration is shown in the following figure.
Figure 3.
MetaSwitch Network Topology
The MetaSwitch VP3500 serves as the Intercept Access Point (IAP) for lawful surveillance and provides the Delivery Function (DF) to the appropriate Law Enforcement Agency Collection Functions (LEA CF). The VP3500 CALEA implementation supports surveillance on subscribers connecting in any of the supported configurations. The Administrative Function of the MetaSwitch EMS System allows the configuration of the lawful surveillance based on the court warrant received.
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4.10 ADDITIONAL REQUIREMENTS
The CALEA implementation for the VP3500 does not require additional configuration elements. The standard VP3500 configurations are capable of CALEA support. The one additional component required is the secure router for secure communications for the CDC delivery to the LEA CF. The choice of the router utilized is up to the discretion of the TSP in conjunction with the LEA requirements.
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CALEA and Next-Generation Networks: A MetaSwitch White Paper
5. CONCLUSION
Carriers should ensure that their network equipment providers understand the issues involved in supporting CALEA and can provide suitable handover interfaces to deliver both call content and call identifying information to a LEA. The TIA and other standards bodies have not yet reached agreement with LEAs on how pure-IP carriers, which do not have any means to fit in with existing directory numberbased CALEA infrastructure, should handle electronic surveillance. However, most nextgeneration carriers already allocate subscribers’ directory numbers in order to allow incoming call routing from the PSTN. These carriers can comply with their CALEA obligations by using a network model like the one described above, in which calls using the carriers’ networks are always routed via carrier-owned access gateways to ensure that subscribers see no change in service or signaling when an intercept is in progress. The MetaSwitch VP3500 Next Generation Class 5 Switch supports this network model by enabling lawful interception for any form of network access, using the J-STD-025A standard. As a division of Data Connection, a well-established and stable privately held company, MetaSwitch stands ready to provide ongoing CALEA-compliance support to its customers.
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6. METASWITCH AND DATA CONNECTION
As a division of Data Connection, MetaSwitch leverages more than 21 years of experience supplying communications technology and support to the leading service providers, including Verizon, SBC and BT, and major equipment vendors. Our engineering expertise is derived from success developing world-leading products, including the core protocols (MGCP, Megaco/H.248, MPLS, IP Routing, SIP, …), applications (unified messaging, conferencing, …) and next-generation switching technology (MetaSwitch VP3500). Data Connection is a consistently profitable and stable private company, creating a basis for long-term investment and growth that ensures our ability to fund ongoing product investment and deliver first-class customer support.
MetaSwitch has offices in Alameda (California), Dallas (Texas), Reston (Virginia), and Enfield (North London), Chester and Edinburgh in the UK.
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7. GLOSSARY OF TERMS USED
AF: Access Function. ASN.1: Abstract Syntax Notation One. CALEA: Communications Assistance for Law Enforcement Act. call: a sequence of events beginning with an initial connection or facility request and ending with the final release of all facilities used. A call may have one or more legs. call content: see content. content call content channel (CCC): the logical link between the device performing an electronic surveillance access function and the LEA that primarily carries the call content passed between an intercept subject and one or more associates. (CDC): call data channel (CDC): the logical link between the device performing an electronic surveillance access function and the LEA that primarily carries call-identifying information. callcall-identifying information: defined in CALEA Section 102 to be “dialing or signaling information that identifies the origin, direction, destination, or termination of each communication generated or received by a subscriber by means of any equipment, facility, or service of a [TSP].” Call-identifying information is “reasonably available” to a TSP if it is present at an intercept access point and can be made available without the carrier being unduly burdened with network modifications. As interpreted by this interim standard: destination is the number of the party to which a call is being made (e.g., called party); direction is the number to which a call is re-directed or the number from which it came, either incoming or outgoing (e.g., redirected-to party or redirected-from party); origin is the number of the party initiating a call (e.g., calling party); and termination is the number of the party ultimately receiving a call (e.g., answering party). called party: the destination party of a call. calling party: the originating party of a call. CCC: call content channel. CDC: call data channel. CF: Collection Function. channel: an independent path for communicating between two points. circuit: a switchable bi-directional path between two locations. A circuit may be all or part of a channel. On an end-to-end circuit, separate physical facilities may be used for each segment of the circuit.
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circuitcircuit-mode: a communication using bi-directional paths switched or connected when the communication is established. The entire communication uses the same path. collection function: defined in FCC 99-230, CC Docket No. 97-213 to be “the location where lawfully authorized intercepted communications and call-identifying information is collected by a law enforcement agency (LEA).” Commission: defined in CALEA Section 102 to be “the Federal Communication Commission.” Committee T1 Committee T1: is sponsored by the Alliance for Telecommunications Industry Solutions and accredited by the American National Standards Institute to create network interconnections and interoperability standards for the United States. content: defined in 18 USC 2510 to be “when used with respect to any wire or electronic communications, includes any information concerning the substance, purport, or meaning of that communication.” DF: Delivery Function. DTMF: Dual-Tone Multi-Frequency. government: defined in CALEA Section 102 to be “the government of the United States and any agency or instrumentality thereof, the District of Columbia, any commonwealth, territory, or possession of the United States, and any State or political subdivision thereof authorized by law to conduct electronic surveillance.” IAP: Intercept Access Point. intercept: defined in 18 USC 2510 to be “the aural or other acquisition of the content of any wire, electronic, or oral communication through the use of any electronic, mechanical, or other device.” Intercept Access Point (IAP): a point within a telecommunication system where some of the communications or call-identifying information of an intercept subject’s equipment, facilities and services are accessed. intercept subject: a telecommunication service subscriber whose communications callidentifying information, or both, have been authorized by a court to be intercepted and delivered to an LEA. The identification of the subject is limited to identifiers used to access the particular equipment, facility, or communication service (e.g., network address, terminal identity, subscription identity). Law Enforcement Agency (LEA): a government entity with the legal authority to conduct electronic surveillance (e.g., the Federal Bureau of Investigation or a local police department). leg: a bi-directional call path associated with each network facility usage attempt and subsequent usage. POTS: Plain Old Telephone Service. This usually refers to loop start lines with DTMF (tone) dialing or decadic (rotary) dialing.
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PSTN: Public Switched Telephone Network. release: to place facilities used for a connection in the idle state where they can be used for other connections. surveillance: refers to electronic surveillance. telecommunication service provider (TSP): defined from CALEA Section 102 to be “a person or entity engaged in the transmission or switching of wire or electronic communications as a common carrier for hire, and includes 1) a person or entity engaged in providing commercial mobile service, or 2) a person or entity engaged in providing wire or electronic communications switching or transmission service to the extent that the Commission finds such service is a replacement for a substantial portion of local telephone exchange service and that it is in the public interest to deem such a person or entity to be a [TSP] for purposes of this title. This does not include 1) persons or entities insofar as they are engaged in providing information services, and 2) any class or category of [TSPs] that the Commission exempts by rule after consultation with the U. S. Attorney General.” Telecommunications Industry Association (TIA): a full-service trade association representing providers of communications and IT products and services for the global marketplace. TIA is accredited by the American National Standards Institute to develop American National Standards used in the industry. TIA represents the communications sector of the Electronic Industries Alliance (EIA). termination: an incoming call attempt.
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