CALEA IMPLEMENTATION IN VoIP NETWORKS

Thursday - 02/24/05, 8:15-9:00am

By Cemal Dikmen, Ph.D.

General Manager Lawful Intercept Products SS8 Networks, Inc.

Regulatory Update - VoIP

      DoJ/FBI/DEA petition filed on 3/10/04 asked FCC to initiate proceeding to resolve outstanding issues delaying CALEA implementation.

FCC has initiated a process called Notice of Proposed Rule Making (NPRM) on 8/4/2004 to clarify the issues regarding interception of IP traffic. The comments from DoJ, service providers, and vendors were filed on 11/8/2004. The reply comments were filed on 12/22/2004. The decision is expected in mid 2005. NPRM tentatively concludes that CALEA applies to:   Facilities-based providers of broadband internet access; Providers of “managed” VoIP service.

Why  both broadband and managed VoIP providers?

Communications identifying information and content may only be available by access to both broadband access and VoIP providers.

VoIP providers such as Vonage are probably going to be covered under CALEA under the FCC’s upcoming decision. Peer-to-Peer communications such as Skype will probably not be covered under CALEA.

Regulatory Update – IP Data

    Based on the NPRM on 8/4/2004, CALEA law .

Facilities-based providers of broadband internet access are expected to be covered under the

Why broadband service providers?

 Communications identifying information and content may only be available by access to both broadband access and VoIP providers.

The specifications for IP interception are not available yet. Old wiretap rules still apply – deliver everything to the LEA.

Likely cause concerns over privacy. Need to define call identifying information clearly for Pen Register & Trap and Trace type court orders.

Regulatory Update - PoC

     Push-To-Talk over Cellular (PoC) in many cases uses VoIP technology over wireless data networks.

Several major wireless service providers are planning PoC deployments.

FCC has already declared that Push-To-Talk over Cellular (PoC) is subject to the CALEA requirements. TIA is working on creating new lawful intercept specifications for PoC. The new specifications are expected to be published mid 2005.

The difficulty is obtaining information and call events from all the conference participants.

Requirements for Lawful Interception

       Access to the information – Define Intercept Access Points Provision the court order and define the target’s identity at the Intercept Access Points Receive information from the Intercept Access Points to/from the target’s communication channel Format the intercepted information based on the standards Filter the information based on the court order Deliver the intercepted communications to one or more authorized law enforcement agencies Collect, store, and analyze the intercepted communications

Common CALEA Implementation

Demarcation Point

Service Provider LEA Court Order Provisioning (a)

SPAF

Intercept Access Points (IAP) Call Data Events (d-CII) Call Content (d-CC) Delivery Function (DF) Call Data Channel (e-CII) Call Content (e-CC) Collection Function (CF) Proprietary Internal Network Interface Standards Based Handover Interface

Lawful Intercept Standards

       

J-STD-025 Rev. A – For interception in wireless and wireline circuit-switched networks.

J-STD-025 Rev. B – For interception of packet data telecommunications services (e.g., cdma2000 ® packet data).

PacketCable™ – For interception of Voice over IP (VoIP) type telecommunications services. The first specifications for VoIP interception.

T1S1 T1.678 – Lawfully authorized electronic surveillance for voice over packet technologies in wireline telecommunications networks.

ETSI TS 101 671 – Defines the handover interface for interception of telecommunications traffic.

ETSI TS 133 106, 133 107, 133 108 – Define interception in a GPRS/UMTS network. ETSI TS 102 232 – Defines the handover interface for IP delivery.

ETSI TS 102 233 – Defines the handover interface for E-mail interception.

Intercept Access Points in PacketCable™ Architecture

  

CMS (Call Management System)

The Call Management System (CMS) provides service to the subscriber. The CMS is responsible for intercepting the Call-Identifying information.

Cable Model Termination System (CMTS)

The Cable Modem Termination System (CMTS) which controls the set of cable modems attached to the shared medium of the DOCSIS network. The CMTS is responsible for intercepting the Call Content, and certain call identifying information.

Media Gateway (MG)

The Media Gateway (MG) is designated as an Intercept Access Point for purposes of intercepting Call Content for redirected calls to the PSTN.

PacketCable Voice Intercept - CMTS

Service Provider Domain

LI Administration Function Law Enforcement Collection Function Call Management Server (CMS) Admin CDC Customer Premise IAD (SIP, H.323, or MGCP based Gateway) Call Control COPS Request Voice Packets RTP Stream Call Control CDC CCC Customer Premise IAD (MTA) Target Subscriber CMTS CMTS

PacketCable Voice Intercept – Media GW

Service Provider Domain LI Administration Function Law Enforcement Collection Function Call Management Server (CMS) Admin XCIPIO SSDF FUNCTION CCC Call Forward to PSTN Target Subscriber Customer Premise IAD (SIP, H.323, or MGCP based Gateway) CMTS MGCP Call Control Voice Packets Gateway Call to Target Forwarded Call PSTN

Session Border Controller for VoIP

    A single Intercept Access Point (IAP) for both call identifying information and call content.

Eliminates the need to provision for call content interception in real-time.

Eliminates the dependency on the lawful intercept capabilities of the softswitch, trunking gateway, CMTS and/or edge routers.

Transparent handling of call forwarding type features.

Session Border Controller as IAP

Service Provider Domain LI Administration Function Customer Premise IAD (SIP, H.323, or MGCP based Gateway) Call Control SBC Provisioning and Call Events over TCP/IP Based SS8 Interface IRI XCIPIO SSDF CC Call Control IRI CC Law Enforcement Collection Function Customer Premise IAD Target Subscriber Cisco CMTS And Routers

Technical Challenges

 PacketCable is the most widely deployed implementation and it requires DQoS. Call content interception cannot be performed if CMTS does not support DQoS. This situation created new and different architectures which required Delivery Function to take an active role in call content interception.

 Most of the network elements (Call Management Systems, Gatekeepers, Media Gateways, Aggregation Routers, CMTS, etc.) need to support lawful interception within the distributed IP environment.

  CMS Subscriber Provisioning interface does not address lawful interception provisioning. The target provisioning requires proprietary interfaces.

It is extremely difficult (or sometimes impossible) to capture call identifying information and call content in some of the call features, specifically for the features implemented within the customer premise IAD.

Intercepting Conference Calls

 Conferencing is implemented within the Customer Premise Equipment (CPE) in some of the technologies. In this case, there is no way of knowing a conference is taking place.  Calls are intercepted as individual calls.  There is no call data information to report conference events.

 Each leg of the call content is delivered to the LEA separately.

Hosted Conference Service

Service Provider Domain

Conference Server PSTN TGW Customer Premise IAD 1-800-CONFERENCE CMTS Target Subscriber IP Network CMTS

3

rd

Party Conference Service

Conference Service Provider

1-800-CONFERENCE

Service Provider Domain

PSTN TGW Customer Premise IAD IP Network CMTS CMTS Target Subscriber

Real Life Problem ! ! !

VoIP Service Provider Call Management Server (CMS) Customer Premise IAD Access Provider Call Control IP Backbone Provider RTP Stream Call Control CMTS Target Subscriber Access Provider Customer Premise IAD CMTS Associate

Delivery Function As A Network Element

The Delivery Function should provide the user with:        Single point for surveillance administration Built-in test tools for remote testing Standard MML and remote GUI support Alarm reporting and Error logging Automatic software fault recovery Automatic or manual disk backup SNMP support for alarm reporting

Thank You ! ! !

Cemal Dikmen [email protected]

Phone: +1.203.567.0603

http://www.ss8.com