WIRELESS Chapter. What is Wireless 9-1-1?

Transcription

1 Chapter 5 WIRELESS What is Wireless 9-1-1?... 1 Three Phases of Wireless Types of Wireless... 2 Wireless Sector & ESN Assignments... 4 Wireless Testing & Network Maintenance Support... 5 Wireless Misroutes... 6 Phase II Deployment... 6 Challenges for PSAPs What is Wireless 9-1-1? Wireless refers to calls placed from wireless devices such as cellular or satellite phones. In contrast to enhanced wireline calls, currently wireless call routing is based on cell tower ESN assignments, not the location of the caller. Consequently calls may not be routed to the PSAP with jurisdiction for where the incident is occurring and transfers may be necessary. In some instances, the call taker may not receive the callback phone number and only the location of the cell tower, not the caller. All these circumstances can present response delays if callers are unable to speak, do not know where they are, or if the call is dropped before the caller can provide their location. Many stakeholders, including the wireless providers, are working to improve call routing accuracy and the precision of location information delivered with the call. California Public Utilities Code 2892 (c ) allows local PSAPs to take wireless calls directly when wireless requirements are met and an agreement is reached between the PSAP, the California Highway Patrol (CHP), and the State Branch. However, PSAPs are not required to take these calls, but encouraged to do so when possible. When PSAPs do not take calls directly, the CHP will continue to receive the calls and transfer them to the appropriate PSAP, or secondary PSAP as necessary. County Coordinators are encouraged to recommend that PSAPs accept CCRM V

2 wireless calls for their jurisdiction in order to both minimize transfers and improve call answer times. As is the nationally recognized emergency number, the use and advertisement of 10-digit emergency numbers in place of accepting wireless calls is discouraged. Three Phases of Wireless While there are three phases of wireless 9-1-1, the State Branch has elected to deploy only direct Phase II to PSAPs. Wireless Service Providers in California may not deploy Phase 0 or Phase I initially and then request to upgrade to Phase II. Any exceptions to this directive shall be reviewed by the County Coordinator and the State Branch. This does not mean however, that all calls are delivered to the PSAP as Phase II. Most calls arrive at the CPE as Phase I and require a rebid to obtain the Phase II location data. Phase 0 The most basic phase is called wireless Phase 0, which means a 911 call is routed automatically to a CHP dispatch center. The call taker does not receive any telephone number or location information other than what the caller can provide. Due to California Wireless deployment requirements, Phase 0 calls are very rare in California. Phase I Wireless Phase I was the first step in providing better emergency response to wireless callers. For Phase I, a wireless call arrives at the PSAP with the phone callback number and tower location. The callback number provides the ability to get the caller back on the line if the call is dropped and it provides the possibility of obtaining subscriber information from the wireless provider. The drawback of Phase I is that it does not provide any location information for the caller. Phase II Wireless Phase II provides call takers with both the caller's wireless phone number and their approximate location information in the form of latitude and longitude. Call takers need to take into consideration the uncertainty (meters) and confidence (percent) shown on the ALI screen when determining a caller s location. When using latitude and longitude to determine a caller s location, dispatchers should think of the location as an area and not a point. To locate wireless callers, Phase II must have been implemented by local PSAPs and wireless carriers and the caller must have a phone capable of transmitting the location information. Types of Wireless Wireless technology continues to evolve rapidly to better serve the huge growth in users and bandwidth demand. NENA has referred to the wireless market in the US CCRM V

3 as having 105% penetration which means many people have more than one device. In addition to the actual phones evolving, wireless providers have sought ways to handle more calls at one time and to allow for greater bandwidth, or space on the airwaves for data transmission. This has lead to a variety of ways to route calls to the PSAP: Traditional macro cell tower. These can be towers or antennas posted on the sides of buildings. The most common macro towers have three or more sectors that from the air looking down, appear like a piece of pie. Each of these sectors can be routed to a different ESN, or PSAP. An omni directional antenna is a single antenna that has no sectors and is routed to a single PSAP. FIGURE 5.1: SECTORED TOWER (LEFT) AND OMNI TOWER (RIGHT) Small cells Indoor & Outdoor. Small cells can be referred to as picocells, femtocells, or microcells and typically have a range of less than 5000 square feet. Latitude and longitude for microcells will be for the tower and not the handset, however this could change in the coming years. Consequently, rebids won t change the location unless the call is handed off to another tower. Calls can be routed via the wireless network or with some products, 911 wireless calls will be routed via a broadband network. o AT&T: FIXED ATTMO will appear in the wireless provider field and the tower address is the address of the owner. o Verizon/Sprint: route as a wireless call with no indication it s a small cell Increasingly we expect to see small cells utilize specific location information such as 3 rd floor, Section R, or Indoor within the call data record and will be identified on the Test Validation Worksheet (TVW) when sector assignments are made. Indoor microcells should be routed by the County Coordinator to the local PSAP, not CHP. CCRM V

4 Distributed Antenna Systems (DAS). Wireless providers are using distributed antenna systems to fill in areas that have high bandwidth usage or interrupted coverage due to urban canyons. DAS have a small coverage area of about 100 m because of the lower power utilized (0.25 watt). For DAS systems the x,y location is taken from the DAS remote box and not the macro tower nor the actual antenna. DAS can be mounted on light and power poles, buildings, or other elevated sites. DAS sites may not have a complete address on the TVW but be shown as an intersection. Wi-Fi hot spots. Wi-Fi hot spots will route wireless calls via the broadband network. The caller location will show up as the address for the fixed VoIP router on the Wi-Fi device. ESN assignments for these are based on VoIP processes; refer to the VoIP section of the manual for further. Wireless Sector & ESN Assignments The wireless system has its own set of ESN numbers, separate from the landline and VoIP ESNs. In California, all the wireless ESNs are divided into three geographic areas: northern, mid, and southern California. Each PSAP has a designated wireless ESN and the default ESN is always to a CHP call center. As a coordinator you should have a copy of the document CA Master Wireless ESNs as of xls, which can be obtained by contacting the CA 911 Branch. Each wireless antenna (omni & DAS) and each sector on a tower can be assigned a unique wireless ESN. Sectored towers can have all sectors assigned to a single ESN, or, can have one or more assigned to different ESNs. For omni antenna s there is only one ESN assigned to the entire area covered. CHP maintains wireless call routing for areas that contain major highway corridors but local PSAPs can choose to take the sectors facing away from highways or towers that are set well back from highways. As with deployment (discussed on page 6), accurate routing begins with cell sector maps and antenna addresses provided by the WSP or its representative (i.e. Intrado). Post-deployment, call statistics on transfers from a specific sector may aid in assessing which PSAP should take the calls on a primary basis. A discussion between the CHP and the PSAP to determine who best serves the area should occur if necessary. Completing the TVW: The TVW will come to the coordinator with the majority of the fields filled in, including Carrier Recommended Routing (PSAP), by the WSP contractor (usually Intrado). County coordinators should make every effort to review and complete the TVW so that CHP may also respond within the allotted 15 days. If the coordinator needs more time, work with the wireless provider otherwise the recommended routing on the form will be completed. If it is incorrect, a cost may be charged to the PSAP(s) to correct the routing. The boxes on the TVW that are filled with yellow are areas the coordinator can make changes in. At a minimum, the PSAP to Receive Wireless CCRM V

5 Calls and Wireless ESN should be filled in by the coordinator (unless you have an agreement with CHP that they do your wireless ESN assignments). As mentioned before, sectored towers can route to different answering points. Based on the mapped coverage area of the sector, the county coordinator should determine if the calls should route to CHP or to the local PSAP. If going to a PSAP, the coordinator should confirm with the PSAP manager that they are willing to take the sectors before completing the TVW. If the calls will be going to CHP, complete the TVW and send it to CHP for their concurrence and approval of routing. Finally, the coordinator should fill in the MSAG Coordinator field with their name and the date, and if the majority of the sectors are going to a PSAP, the PSAP representative name, date, and 24x7 PSAP administrative number. Distributing the TVW: Once your TVW is complete route it to CHP at ccss@chp.ca.gov, but do not copy Intrado to avoid confusion. CHP will review the TVW and once approved, it to Intrado and copy the coordinator. Wireless Testing & Maintenance Support Post deployment wireless service providers will continue to upgrade their networks and conduct routine maintenance on their systems. County Coordinators assist the PSAPs and WSPs in this endeavor by helping to coordinate test wireless calls being placed into the PSAPs. Depending on the needs of your county, you can develop a process that works best for your PSAPs, but some standardization is highly recommended. For example, large counties such as Los Angeles give each wireless provider a day of the week to test on and they aren t required to wait for approval for every test. They know their day, the PSAPs know the day each provider tests on, and the network testing is completed without the coordinator having to touch every test request. Another example, used in smaller counties, requires PSAPs to provide their preferred testing window (day and timeframe) and the coordinator can then approve any testing that falls within that window without having to contact the PSAP first, however, notice of testing should always be sent to the PSAP (unless the PSAP(s) and coordinator have established a set agreement ahead of time). If approved testing comes at an inopportune time, dispatchers always have the discretion to tell the tester that they can no longer accommodate the incoming test calls. Further, if PSAPs experience problematic unauthorized testing or have problems with a tester, they should advise their county coordinator who should follow-up with the WSP. CCRM V

6 Wireless Misroutes A true wireless misroute is when the incorrect ESN has been assigned to a sector, tower, or antenna. For example, in a county where CHP takes all wireless calls in the unincorporated area, and the Sheriff takes wireless only for sectors within contract cities, a wireless call routed to the Sheriff s Office from a tower that is not near a jurisdictional boundary would be a misroute. In this situation, the Sheriff s wireless ESN for a contract city was assigned in error to a tower in the unincorporated county. In summary, a misroute is where a tower or tower sector that should be assigned to one PSAP, routes to another in error. The location of the caller has little to do with the routing of the call. Network congestion as well as atmospheric conditions can cause the wireless signal to be sent to a tower further away from the caller by the network, and consequently may appear to be a misroute to the call taker. Thorough investigation is necessary if the coordinator can not determine a clear misroute situation (incorrect ESN assigned to a sector). Phase II Deployment For PSAPs New to Wireless The majority of PSAPs in California have already begun taking wireless calls, so the steps for deployment from scratch will not be necessary. However, if you have PSAPs in your county who would like to start taking wireless calls, you will need to follow the procedure outlined below. How to know if PSAPs are ready for deployment CPE must be Format04/Multi-steering. CAD must be able to accept format04. CPE must have the rebid/retransmit capability. Work with LEC to determine if existing star codes for fire transfers can be used. Suggest to PSAP they have a wireless standard operating procedure (SOP) for call handling. Familiarize dispatchers with wireless ALI and call handling Initial steps for PSAP deployment: Encourage the PSAP Managers to contact the State Branch and other previously deployed PSAPs to discuss call volume increases and staffing concerns. PSAP sends Letter of Agency to the State Branch that they will accept wireless calls CCRM V

7 State then sends out a Request for Service package which includes carrier letters to the PSAP for signature PSAP returns entire package to CHP for signature CHP signs and forwards to the State Branch The State Branch prepares deployment packages and notifies WSPs. The WSPs must deploy within 6 months or request a waiver. During the pre-deployment process, PSAPs may receive questionnaires from the database providers (Intrado, TCS). These questionnaires often request information that the PSAP personnel may not know. The forms are not critical for deployment and at the discretion of the PSAP may be completed with as much information as possible. For additional wireless information see: County Coordinator Wireless Responsibility The Wireless Coordinator role started out as a regional position responsible for checking jurisdictional boundary maps, organizing routing meetings, building the wireless MSAG, checking status of trunk lines with the State Branch Wireless Coordinator, and coordinating testing. As the deployments have progressed, responsibilities have transitioned from regional coordinators to the County Coordinators. When deployment is requested, County Coordinators should do the following: Assist the PSAP with the process to be able to take Wireless calls. Contact the State 911 Branch for wireless ESN assignments for each PSAP requesting deployment. Establish the wireless MSAG using California Wireless Critical Data template. See Appendix E Wireless and VoIP. For wireless issues, Intrado and/or TCS will be your point of contact. The wireless service providers will contract with Intrado or TCS (3 rd party vendor) to manage deployment responsibilities including mapping, and testing. The State 911 Branch should notify the County Coordinator when deployment letters have been sent to WSPs. The County Coordinator should stay in contact with the PSAPs to confirm the deployment process has been initiated. The County Coordinator will be contacted by Intrado or TCS when maps are ready for PSAP and CHP approval. CCRM V

8 Coordinate a mapping meeting with the CHP and the PSAP to establish sector/tower routing. This can be either face to face or electronically, whichever best suits your situation. Routing sheets, also known as Test Validation Worksheets or TVWs, that are submitted electronically will use an electronic signature. CHP will work with the County Coordinator to establish routing. CHP is responsible for returning final approved routing sheets to Intrado/TCS. Intrado/TCS will notify the County Coordinator of how many days will be needed for testing. Discuss deployment dates, times and the overall process with the PSAP. The deployment timeline will depend on the number of sectors. Determine the time that the PSAP can staff to accommodate testing. The PSAP has final authority on the testing schedule. Testing may be canceled at any time for any reason. During deployment discussions, the County Coordinator may request additional drive testers to shorten testing time line. It is highly recommended that the County Coordinator is on premises for first WSP deployment and to monitor the conference bridge during any additional deployments to offer assistance. It is highly recommended that the CPE technician be available at the PSAP during initial wireless deployment to address any equipment issues. Confirm that the WSP has arranged LEC support for each deployment to aid with translation or call routing issues that may occur. What to expect during deployment A conference bridge will be established by Intrado/TCS for all parties involved with deployment This includes the LEC, Intrado/TCS, Field Testers, and the County Coordinator. The PSAP may join if desired. A drive tester (provided by Intrado/TCS) will generate test calls from all sectors reflected on the approved routing sheet (TVW). o The tester should immediately identify each call as a test. o WSPs all use different technologies (examples are TDMA, CDMA, IDEN, GSM, UMTS.) and therefore must test each of the technologies available on a particular site. CCRM V

9 o Expect moderate to long periods between test calls to allow for the drive tester to move from one tower to another. The drive tester should ask the PSAP to verify the following information from the ALI (see Appendix E for ALI display): o Call Back Number o Address of tower o Pseudo ANI (PANI) o That the call routed to correct PSAP o Sector directional o Class of Service (COS) o Rebid/Retransmit o NENA ID o WSP number o Community Name Note: Various WSPs handle this process differently. It is strongly recommended that the PSAP do the following: o Verify that the ALI screen is formatted correctly. o If PSAP has mapping, verify that the latitude and longitude plot correctly. o PSAPs should test their ability to transfer calls via the network using star codes to other agencies (CHP, fire dispatch, etc.) and confirm that a complete ALI is being received. o PSAPs should attempt a rebid that may cause class of service, latitude/longitude, and meters and percent to change. o Non-initialized phones (not assigned a carrier) will also be tested. PSAPs should usually see an area code of 911 displayed on these types of calls. o It is not uncommon for Intrado/TCS to shut down the conference call bridge after the first few calls have been verified to route to the proper PSAP. If you wish, insist that the bridge stay open. It is also not uncommon for the bridge to be used by the WSP simultaneously for multiple deployments in the state. CCRM V

10 o Educate call takers on proper use of toll-free WSP telephone number that appears on the ALI screen. This telephone number is used in exigent circumstances to obtain subscriber information from the WSP. Most WSPs require a form to be completed and faxed to them. Samples of these forms can be found in Appendix B Forms and Examples. What to expect post deployment PSAPs may contact the County Coordinator concerning the following: o Misroutes should be referred to the County Coordinator who will involve Intrado or TCS, depending on the WSP, as needed. o Incorrect address information of cell site displayed on ALI screen. Corrections should be referred by the County Coordinator or PSAP to Intrado or TCS, depending on the WSP. o Functionality or technical issues handle on a case-by-case basis. Post-deployment packages should be provided by each WSP after each PSAP completes testing. Packages include contact information, procedures of that WSP, and other helpful information. All WSPs will conduct maintenance activities following initial deployment. Examples of activities include redirecting a sector, adding a tower, changes in the network, and changes in designations of towers or sectors. Some of these activities will require routing sheet approvals and/or test calls to PSAPs. The County Coordinator will schedule testing as needed. This may be a pre-established schedule or a case-bycase test at the discretion of the County Coordinator in consultation with the PSAP and WSP. A sample of a pre-established schedule can be found in Appendix E Wireless and VoIP. Other Red Project - In 2008 it was determined that a change was needed to more efficiently route wireless calls in California. The State Branch contracted with an independent vendor to evaluate Phase II wireless call data. This endeavor is known as the RED (Routing on Empirical Data) Project. Any questions regarding this project should be directed to the State E9-1-1 Project Coordinator. GIS Funding - The State Branch provides one-time GIS funding for PSAPs that commit to answer Wireless calls directly. Information on requirements and the process to obtain funding can be found at: under GIS Spending Plan Guide. CCRM V

11 Challenges for PSAPs Rebids required on wireless calls for Phase II location information In 2010 wireless providers were advised by PSAPs that better location information was needed, not a bad location quickly. Consequently, wireless providers moved to Assisted GPS in their networks with the understanding that it would take up to 30 seconds to get a Phase II location delivered. Calls were expected to continue to be delivered to the PSAP in much less than 30 seconds so that voice contact could be made. The unforeseen consequence of this change was that statistics of Phase II delivery on initial delivery plummeted. Many dispatchers weren t clear on the need to rebid to pull Phase II data from the wireless provider, nor of the time restrictions for how quickly rebids could be done (20-30 seconds apart in most cases). Auto rebidding has been posited as a solution for dispatchers having to take their focus away from a call to rebid for Phase II data. Customer Premise Equipment can be set up to auto rebid at the timeframe specified by the PSAP. The recommendation has been to rebid 30 seconds from intercept. If setup time is 15 seconds, then rebid time should be at 15 seconds allowing 30 total seconds for the calculation. The Ca 911 Branch can assist PSAPs with determining their set up times from ECaTS. Coordinators may wish to touch base with the County Coordinator Task Force to see what the current status of wireless rebids is with PSAPs in California. Early adopters reported some problems with auto updates to CAD (wiping out a good address given by the caller) and additional CAD events being created as new location information is spilled to CAD. Non-initialized telephones Non-initialized wireless telephones are telephones that are not registered for service with a Wireless Service provider. Because carriers generally do not assign a dialable number to a handset until a customer enters into a service contract, a non-initialized telephone lacks a dialable telephone number. Examples of these types of telephones include only telephones and unsubscribed cellular telephones,. ANI will be received as (911) NXX-XXXX and cannot be called back. The seven digits following 911 are the last seven of the phone s International Mobile Equipment ID or IMEI number. WSP information shown on the ALI screen only indicates the owner of the tower. That WSP will not be able to provide subscriber information for the caller abuse A harassing/repeat wireless caller is defined as a person who maliciously places more than 100 harassing/repeat wireless calls to a PSAP. Callers misusing or abusing the system with a wireless phone are more difficult for the PSAP to identify and locate and, consequently, more difficult to take action to address. CCRM V

12 PSAPS have a variety of resources they may use to resolve these situations. In order to collect statistics on active and previous harassing/repeat callers, the State Branch requests that County Coordinators collect specific information on calls and send it to them. An Excel spreadsheet to assist with this can be found in Appendix E. Pre-paid wireless telephone service Wireless pre-paid phones are available at many stores. If there are no minutes available, the phone can still be used to call Pre-paid phones will often retain the telephone number and provide good location data even if there are no minutes available, however, subscriber data is often unavailable or unreliable. 911 calls will appear as a non-initialized phone when: A call is made from a Non-initialized telephone A subscribed phone is roaming on another carrier s network. A loss of connectivity to the service provider s tower occurs. For example, if the subscriber is driving through a tunnel and loses connectivity, the call still might be delivered to the PSAP but may not have the associated call-back number or location information. International telephone numbers In most cases, International telephone numbers are longer than 10-digits and the CPE at the PSAP can only accept 10 digits. This results in only a portion of the telephone number appearing on the ALI screen which may look like a standard (NPA) NXX-XXXX. There is no way for a call taker to identify the telephone as an international caller. Satellite telephones Satellite telephones with capability will normally be answered by a third party call center. The call center will then forward the caller to the PSAP, possibly via PSTN. Tip: There are known anomalies that are not listed above. It is strongly recommended to participate in the monthly County Coordinator conference calls to remain educated on the changes with wireless technology. CCRM V