Carriers must provide law enforcement agencies with additional capabilities to intercept messages sent over not only traditional telephony networks, but next-generation wireless and IP networks as well, giving those agencies access to data communications and encompassing email, Web surfing, and instant messaging.
The Center for Democracy and Technology (www.cdt.org) puts the number of traditional wiretaps on circuit-switched networks at approximately 1,000 annually, and 68,000 annually for lower-standard surveillance. But those numbers are expected to explode, as the government has greatly broadened the authority of law enforcement (police, customs, immigration, and internal security agencies) and intelligence agencies to intercept next-gen packetized networks-purportedly a major vehicle for illicit activity. For a look at what the American public feels about privacy invasions, see "Privacy Public Opinion".
The challenge for carriers lies in figuring out how to monitor enhanced features in traditional networks, and to intercept packets in next-generation wireless networks, consisting of softswitch and media gateway technologies.
"For one, enhanced services like call forwarding or enhanced dial digit features made traditional wiretapping insufficient, as it became harder to track calls once they are bounced around," says William Stofega, an analyst in IDC's program for residential and small-business telecommunications services. He and IDC group vice president, Mark Winther, have co-authored the report "The Market for Lawful Intercept Solutions: From the Circuit Switch to Next-Generation Networks and Beyond."
Challenges of Next-generation Lawful Intercept
However, the challenges inherent in circuit-switched networks pale compared to those in softswitch architectures. "Media servers in softswitch networks propose to be the core network resource for media-intensive applications, such as voice messaging, conferencing, playing announcements, dual-tone multifrequency touch-tone signals, and so on," says Stofega.
Replicating call content with media servers is complicated, and standards have yet to be written to address those issues.
"The complications with next-gen networks arise from the multiple potential access points that must be intercepted if monitoring packetized voice networks. Routers, softswitches, application servers and media gateways, as well as traffic flow [local, national, international transit, and origination and termination networks], must all be considered," explains Stofega. Add the fact that packets go to different locations in different directions: "RTP sessions go via one route," he says, "while MGCP or SIP sessions go another."
At the moment, government and industry representatives are still hashing out standards for packet-based networks. "I don't think standards that have the approval of both industry and government will materialize until the end of 2003 at the earliest," says Stofega, although, there are organizations working now to resolve issues.
For example, the 3rd Generation Partnership Project (3GPP) Association is developing specifications to standardize CALEA/European Telecommunications Standards Institute (ETSI) compliance in 3G wireless packet networks, and CableLabs has already defined a specification (PacketCable) for packetized voice on cable networks that has applicability to other wireline networks.
3GPP has yet to define architecture and interface specifications for CALEA based on the CDMA2000 core network; however, CableLabs has defined four network elements with PacketCable. As outlined by IDC, the elements are:
o Cable Modem Termination System (CMTS), which intercepts call content and call-identifying information
o Call Management System (CMS), which provides service to customers and designates the IAP (intercept access point) for intercepting call-identifying information
o Media Gateway (MG), which is an IAP for call content in redirected calls to the PSTN
o Media Gateway Controller (MGC), used to intercept call-identification data for redirected calls to the PSTN.
"The spec allows for other variables, such as the possibility that calls are redirected and do not use the facilities of the subscriber that initiated the redirection," says Stofega. In such cases, PacketCable dictates that the CMS/CMTS of the new destination be used if a call is redirected to another PacketCable endpoint within the same provider's network. If redirected to a PSTN endpoint, the MGC/MG of the PSTN interconnection is designated as the IAP, which represents a point within a carrier's network where the intercept accesses some of the call content or call-identifying information of the subject's equipment, facilities and services.
"CALEA/ETSI compliance in wireless networks will be a challenge sometimes," says Stofega, noting that roaming interception becomes complicated according to what type of roamers a carrier supports.
"There are remote roamers and visiting roamers," he explains. The former is a home network subscriber traveling out of network; the latter is a subscriber of a remote network served by the home network. Intercept is possible for both incoming and outgoing calls, but it requires two IAPs: a mobile switching center (MSC) and home location register (HLR) to provide identity and location while roaming.
Carnivore is the name for a controversial FBI surveillance tool that acts like a virtual "vacuum cleaner" in trunk lines that sucks up bits and bytes out of COs. Debates rage, however, over how to make sure that law enforcement doesn't pull out data it's not supposed to, since wiretap orders are specific about the type of data the law enforcement agency may obtain (for more on Carnivore, see "Carnivore: FBI's Packet Sniffer May Have Loose Fangs," Billing World & OSS Today, April 2002).
Increased CALEA Expectations
In the meantime, CALEA requires operators of both fixed and cellular networks to supply data to law enforcement, as well as allow direct, real-time access to phone calls and faxes as they happen.
Three types of intercept will be recognized under CALEA, according to IDC, including full-content conversations (Title III or Foreign Intelligence Surveillance Act); pen register, which captures outbound call-identifying information (not call content) of parties the subject calls; and trap and trace, which captures inbound call-identifying information of parties being called (not call content).
CALEA also requires carriers to upgrade equipment purchased before Jan. 1, 1995, to a telecom intercept capability. (That upgrade will be at government cost; $500 million was allocated to reimburse carriers for modifying equipment installed before Jan. 1, 1995. However, the same has not happened for next-gen networks.) Manufacturers must work with industry and law enforcement to ensure that their equipment meets federal standards.
The J Standard
The J STD-025 Lawfully Authorized Electronic Surveillance (LAES)-commonly known as the J Standard, promulgated by the Telecommunications Industry Association (TIA)-is a response to CALEA requirements and one to pay attention to, according to IDC's Stofega. It specifies how to collect call-identifying and content information from wireline, cellular and broadband personal communications services. "The standard defines the intercept function in access, delivery, collection, service provider administration and law enforcement administration," Stofega says.
The J Standard is not a cure-all, however, since it does not define a standard way to trace packets to their destinations. It focuses more on the circuit-switched world, rather than the IP-based world of next-generation switches.
Vendors are coming out with solutions in that vein, but none can be called a standard yet.
In addition to monitoring capabilities outlined in the J Standard, carriers should heed the FBI "punch list" of mandated CALEA functions (see "FBI Outlines CALEA Requirements").
In connection with the FBI punch list, Stofega points out that the FCC has adopted six of the nine; those not adopted have been remanded for reconsideration and were reinstated by a federal court in April 2002.
The FCC is charged with regulating the use of wire and radio communications. Defining its role under CALEA, Congress assigned it specific responsibilities, which include defining what constitutes a telecommunications carrier for the purposes of CALEA; establishing technical requirements or standards for compliance; reviewing petitions for an extension of the capability compliance date; and prescribing rules necessary for the implementation of CALEA.
The IDC report also indicates that service providers have three principal ways to provision lawful intercept capability in a telecommunications network, according to CALEA/ETSI guidelines. First is the standalone use of passive monitoring to intercept one or more open interfaces between different functional entities in the network, such as bugging a specific phone with alligator clips on a specific line in a central office. These have proved ineffective with enhanced services, such as call forwarding or roaming in wireless networks.
Second, switch-embedded systems developed by switch manufacturers operate within their own switch operating systems. CALEA/ETSI-compliant software that resides on the circuit switch provisions the wiretap request, intercepts calls and call data, converts calls and call data messages into required legal intercept standard format, and delivers the call data and content to law enforcement monitoring facilities. Scalability and cost have been an issue, as network technologies evolve and multivendor networks proliferate.
Third, server-based (off-switch) systems require minimal changes in existing network infrastructure, but introduce a new network element.Such systems bring flexible architecture to support distributed deployment models. CALEA/ETSI servers support multiple switches and multiple switch interfaces for colocated or centralized deployment, providing a common interface to the collection function.
How the CALEA mandates will affect carriers' back-office systems and strategies is difficult to assess, due to the sensitive nature of the topic. Because the government has mandated stringent demands without offering funding, some carriers, particularly smaller CLECs in rural areas, may not meet all expectations. "No one wants to be seen as unpatriotic or uncooperative to law enforcement in today's climate," says Stofega."However, burgeoning intercept technologies are expensive, depending on volumes, at a time when most of the industry is struggling with shrinking budgets."
Most carriers contacted for this article say they are fully compliant, and as of press time no violations or large fines have been publicly reported.
"To the extent that softswitches are being deployed instead of Class 5 circuit switches, network service providers are typically positioned as a secondary line service provider, thus relieving them of regulatory requirements, such as legal intercept, E911, CAMA trunk interfaces," says Stofega. He notes that smaller rural carriers are worried about the cost to comply. According to IDC research, price points for CALEA/ETSI-compliant software from switch vendors range from $50,000 to about $400,000, depending on the volumes involved. Server-based adjunct systems for TDM and IP networks typically begin at $200,000 and scale up to millions of dollars.
While most large wireless and wireline carriers are achieving CALEA compliance, smaller rural operators are struggling. Since no upgrade funding is available yet for IP-based intercepts, initiatives for service bureau and shared infrastructure solutions are under way at such companies as Verint and Verisign. Those efforts would help small carriers comply with CALEA without shelling out large sums.
| Privacy Public Opinion Just as warrants enabling wiretaps and intercepts of packetized messages over the Internet burgeon, public support regarding such invasions of privacy is decreasing. Although most citizens interviewed for a PSRA/Newsweek poll conducted in June were amenable to increased security measures—such as more ID checks at workplaces, streets and highways, baggage checks, and so on—the majority were against monitoring of private phone calls and emails by law enforcement and the government. According to the PSRA/Newsweek poll, 12 percent "strongly favor" such methods, while 28 percent will "accept it only if necessary," and 57 percent say that it "goes too far." A PSRA/Pew Research Center poll asked citizens how they felt about allowing the U.S. government to monitor their personal telephone calls and emails. Only 26 percent favored this measure to curb terrorism, while 70 percent opposed it. |
| FBI Outlines CALEA Requirements Carriers have a lot of challenges when it comes to complying with CALEA. The following list is the FBI’s “punch list” of mandated CALEA functions: • Conference call monitoring • Party hold, join, drop on conference calls • Subject-initiated dialing and signaling information (call forwarding, call waiting, call hold and three-way calling) • In-band and out-of-band signaling (ringing, busy signals, call waiting tones) • Timing information, which correlates call-identifying information with the call content of a communications interception • Dialed digit extraction, to capture all digits dialed by the subject after initial call setup is completed (PINs), as well as credit card numbers • Surveillance status message, which verifies to a law enforcement agency that a wiretap has been established and is functioning correctly • Continuity check tone that alerts agents if the facility used for delivery of call content interception fails or loses continuity • Feature status message, which notifies a law enforcement agency that, for the subject under surveillance, specific subscription-based services were added or deleted. |
