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CS 479R Telecommunications

CS 479R Telecommunications. VoIP Issues Gary D. Brown, Guest Lecturer Lecture 4. VoIP Issues. Introduction SS7 Network Architecture SS7 Protocols SS7 Call Signaling VoIP Issues VoIP NG 9-1-1. VoIP Issues. CALEA (Wiretapping) LNP (Local Number Portability) Government Regulations

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CS 479R Telecommunications

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  1. CS 479R Telecommunications VoIP Issues Gary D. Brown, Guest Lecturer Lecture 4 UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  2. VoIP Issues • Introduction • SS7 Network Architecture • SS7 Protocols • SS7 Call Signaling • VoIP Issues • VoIP NG 9-1-1 UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  3. VoIP Issues • CALEA (Wiretapping) • LNP (Local Number Portability) • Government Regulations • Taxes • E911 (Emergency Services) UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  4. CALEA • Communication Assistance for Law Enforcement Act • Lawful interception of telecommunications • “Wiretap” law • Wire-line/Wireless Network Compliance • Required for CO and MSC switches • Not applicable to tandem switches • VoIP Network • Required of all VoIP Service Providers • Consumers can use any VoIP gateway or service anywhere at anytime UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  5. CALEA • Wire-line/Wireless Network Implementation • Must reserve switch ports (trunks) for wiretap recording devices • Wiretap recording devices may be remotely located • Must transmit both sides of voice conversation to wiretap recording device • Caller/called party must be unaware • Switch software must enable electronic wiretap • By Calling Line Identification (CLI) • By Destination Number • By Authorization Code or PIN (DTMF tone entry) • Must handle call forwarding and record redirection information • Must record call waiting and 3-way calling information • Must record call signaling information and link to recording • Call signaling information must be searchable UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  6. CALEA • VoIP Network Implementation • Must reserve DSP resources for wiretap recording devices • Up to five (5) simultaneous real-time RTP streams to remote IP-based wiretap recording devices (may be in different IP networks) • Must transmit both sides of voice conversation to wiretap devices • Caller/called party must be unaware • VoIP call server/proxy software must enable electronic wiretap • By Calling Line Identification (CLI), SIP URI or H.323 address • By Destination telephone number, SIP URI or H.323 address • By Authorization Code or PIN (DTMF tone entry) • Must handle call forwarding and record redirection information • Must record call waiting and 3-way calling • Must record call signaling information and transmit within 8 seconds UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  7. CALEA • Lawful Intercept • Requires court order (subpoena) • Must identify target (CLI, destination, authorization code, SIP URI, H.323 address, etc.) • Must be signed by judge and delivered by constable or other peace officer • Telecommunications Service Provider must follow its CALEA compliance procedures to implement • Must have documented CALEA compliance plan with detailed procedures • Must document procedure execution UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  8. CALEA • Telecommunications Service Provider Compliance • All CO/MSC switches—compliance deadlines of October 25, 1998 and June 30, 2002 (extension request grants) • VoIP Service Providers deadline of June 30, 2006 • All Telecommunications Service Providers by April 7, 2007 • Must have documented CALEA compliance plan with procedures • Employees must be trained in compliance procedures • Must fill out and submit “Flexible Deployment Assistance Guide Template” (http://www.AskCALEA.net/FlexD.html) to FlexD@AskCALEA.net • FBI’s CALEA – Flexible Deployment Assistance Guide 4th Edition (May 2004) • OMB Control Number: 1110-0030 (expiration date 4/30/2007) • http://www.askcalea.net/archives/docs/flexguide4.pdf UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  9. CALEA • Telecommunication Device Manufacturers • Wire-line/Wireless devices • ANSI/J-STD-025-A-2003 (April 2003) • Available on www.atis.org online store • VoIP devices • ANSI/J-STD-025-A-2003 (April 2003) • ASN.1 modules for SIP and H.323 • FBI’s Electronic Surveillance Needs for Carrier-Grade Voice over Packet (CGVoP) Service (Issue 1 dated January 29, 2003) • “U.S. Government Restricted—For Official Use Only” • Special handling and control requirements • Must be requested from FBI—cannot be legally obtained from any other source • Is available on several Internet websites UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  10. Local Number Portability (LNP) • Applies to all Telecommunication Service Providers (TSPs) • Wire-line, Wireless and VoIP • Allows consumer to keep telephone number when changing carriers and even technology • Old carrier “ports out” • New carrier “ports in” • Carriers use an LNP service bureau to effect change between them • Service bureau interfaces with each carrier’s Operational Support System (OSS) • Original LNP was for “local” numbers only • Competitive Local Exchange Carriers (CLECs) • Now “Number Portability” but often still referred to as “LNP” UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  11. Local Number Portability (WNP) • Internally-routed “Routing Number” (SS7 term) • Landline Implementation (LNP) • SS7 Service Control Point (SCP) database lookup • Access carrier’s internal network switches use Routing Number to route call to “owner” carrier for call original or termination • Wireless Implementation (WNP) • Wireless “MDN” (Mobile Dialed Number) • Remains with subscriber • Wireless “MSID” (Mobile Station ID) • Changes when porting to different carrier • May be automatically or manually programmed in phone UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  12. Government Regulations • Telecommunication Service Providers (TSPs) • Wire-line and Wireless Service Providers • Resellers and MVNOs (wireless) • VoIP Service Providers (VSPs) • FCC ruled VoIP services are “interstate in nature” and not subject to state regulation • Federal Regulations (all TSPs) • “214” Carrier Registration • Universal Service Fund Contributor • National “Do Not Call” Registry (wireless only) • FCC Prepaid Card Service Provider Certification • State Regulations (not applicable to VSPs) • State Registrations (59) • State Universal Service Fund(s) UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  13. Federal Taxes • Federal Universal Service Fund “Contribution” • Interstate services only • Contribution rate set quarterly • Current quarter (1Q2008) rate is 10.2% • Next quarter (2Q2008) rate is 11.3% • Quarterly FCC Form 499Q (estimate) • Annual FCC Form 499A (actual) • Monthly Invoice • All TSPs including VSPs UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  14. Federal Taxes • Federal Local Number Portability Tax • Paid by all TSPs • Funds all local number porting expenses of all carriers • Currently 0.0002% of TSP’s annual revenue UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  15. State Taxes • State Universal Service Fund Tax • Intrastate services only • Wire-line and wireless only • Vary from state to state • Utah (0.9%) • California has five (5) USF taxes each with rates 0.2% to ~2.5% • New York has no USF tax • State E911 Tax • State Poison Control Tax • State Sales Tax UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  16. County/City Taxes • E911 Tax • Franchise Tax • Sales Tax • Special Service District Tax UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  17. E911 Emergency Services • Basic 911 • Original Emergency Services • Landline only • Telephone number displayed to emergency operator • Could not dispatch if caller could not speak • Problem for dispatchers was (and still is) location of caller • E911 • “Enhanced” Emergency Services • Operator display shows • Telephone number • Address • Guaranteed emergency personnel response even if caller cannot communicate UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  18. Wire-line E911 Architecture PSTN Tandem CO Selective Router ALI Public Safety Answering Point (PSAP) ALI Automatic Location Identification Database UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  19. Wire-line E911 Call Flow • Caller dials “9-1-1” • CO switch routes call [via tandem switch] to “Selective Router” • Selective Router routes call based on caller’s telephone number to appropriate Public Safety Answering Point (PSAP) responsible for caller’s Emergency Services Zone (ESZ) • PSAP queries Automatic Location Identification (ALI) database for address using caller’s telephone number • ALI returns address to PSAP • Telephone number and address displayed on PSAP dispatcher screen UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  20. Wireless E911 Emergency Services • Mobile E911 • Problem #1 – “I can hear you now, but where are you?” • Problem #2 – Cell phone mobility and roaming (not in home area) • Phone GPS Method • Phone contains built-in GPS receiver and sends latitude and longitude coordinates • 3 satellites for latitude/longitude and 4 satellites for lat/long/altitude • Location accuracy convergence with multiple satellite signals takes time • 2.5 minutes per satellite • GPS does not work inside metal enclosures or under water-covered structures or vegetation • Network Triangulation Method • MNO estimates location using signal’s “angle-of-arrival” at cell tower antenna for direction and phone’s power level for distance • Accurate to 500 meter radius • Multiple cell tower triangulation increases location estimation accuracy • Accurate to 200 meter radius • PSAP must request of Mobile Network Operator at time of call • Poor emergency response if caller cannot speak (need address!) UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  21. Wireless E911 Architecture PSTN Tandem CO Selective Router MSC MPC Wireless Network ALI Public Safety Answering Point (PSAP) ALI Automatic Location Identification Database GIS Geographic Information System MPC Mobile Positioning Center GIS UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  22. Wireless E911 Call Flow • Caller dials “9-1-1” and presses “Send” • MSC switch passes MDN, MSID and location information to Mobile Positioning Center (MPC) • MPC sends caller’s latitude/longitude to a Geographic Information System (GIS) • GIS uses latitude/longitude to determine and return civic address and applicable Emergency Services Zone (ESZ) • MPC returns an Emergency Services Routing Key for the ESZ to the MSC(ESRK is a 10-digit E.164 number pre-assigned to a particular ESZ) • MSC routes call [via tandem switch] to “Selective Router” UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  23. Wireless E911 Call Flow • Selective Router routes call to PSAP responsible for ESZ using ESRK • PSAP queries ALI database for caller’s location address using ESRK • ALI looks up ESRK, finds [pre-configured] “wireless shell” record for MPC, and sends ESRK to MPC • MPC uses ESRK to find and return caller’s address • ALI returns caller’s address to PSAP • MDN and address displayed on PSAP dispatcher screen UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  24. VoIP E911 Emergency Services • VoIP E911 • Problem #1 – “I can hear you, but where are you?” • Currently no way to locate physical address of IP devices • Problem #2 – VoIP device mobility • Dynamic IP address assignment • VoIP users must register location of VoIP device • U.S. government required 95% customer registration by Nov 28, 2005 • Non-attainment required VoIP Service Provider (VSP) to cut off non-registered customers (since rescinded) • VoIP devices can be moved without re-registration • Emergency services personnel sent to wrong location • VSP’s have many E911 disclaimers • Current VoIP E911 uses E-2 interface made for wireless UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  25. Wireless E911 Architecture PSTN IP Network ESGW Selective Router Tandem VPC VSP Public Safety Answering Point (PSAP) ALI Automatic Location Identification Database ERDB Emergency [Services] Routing Database ESGW Emergency Services Gateway LIS Location Information Server VPC VoIP Positioning Center VSP VoIP Service Provider ERDB ALI LIS UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  26. VoIP E911 Call Flow • Caller dials “9-1-1” on VoIP device • VoIP device sends IP call signaling information to VSP • VSP passes IP call information to VoIP Positioning Center (VPC) • VPC queries the Location Information Server (LIS) for caller’s registered location information • LIS returns address to VPC • VPC sends address to Emergency [Services] Routing Database (ERDB) • ERDB (a GIS system) locates applicable ESZ and returns an Emergency Service Routing Number (ESRN) and Emergency Service Number (PSAP) to the VPC UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  27. VoIP E911 Call Flow • Based on ESRN/ESN, the VPC allocates an Emergency Services Query Key (ESQK) from a pool of pre-allocated and pre-configured 10-digit E.164 numbers • VPC may optionally assign a temporary Callback Number (CBN) if the VoIP device does not have an E.164 number assignment • VPC sends ESRN and ESQK to VSP • Using ESRN, VSP routes call to Emergency Services Gateway (ESGW) • VoIP device establishes RTP session with ESGW • ESGW routes call with ESQK (as CLI) and ESRN (as destination) to Selective Router (SR) UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  28. VoIP E911 Call Flow • Selective Router routes call to PSAP responsible for ESZ using ESQK • PSAP queries ALI database for caller’s location address using ESQK • ALI looks up ESQK, finds [pre-configured] “VoIP shell” record for VPC, and sends ESQK to VPC • VPC uses ESQK to find and return caller’s address and CBN and the VSP’s 24x7 contact information • ALI returns caller’s address and CBN to PSAP • CBN and address displayed on PSAP dispatcher screen UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

  29. VoIP Issues Next lecture on VoIP NG 9-1-1 UVSC CS 479R – Telecommunications and Voice Over IP VoIP Issues

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