Bandwidth 9-1-1 Implementation Guide

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Molly Katolas

Updated

CONFIGURING YOUR 9-1-1 SERVICES

SESSION BORDER CONTROLLERS (SBCs)

SIP PEERS

SUPPORTED CODECS

SUPPORTED PRIVACY TYPES

MEDIA/AUDIO

OTHER SIP CONFIGURATIONS & SUPPORTED METHODS

 

TESTING YOUR BANDWIDTH 9-1-1 CONFIGURATION

INTEROPERABILITY TESTING STEPS

SIMULATED FAILOVER TESTING

HANDLING SBC FAILURES

SAMPLE INVITES

 

TIPS FOR SUCCESSFUL 9-1-1 TEST CALLS

DOS AND DON’TS WHEN MAKING 9-1-1 TEST CALLS

GENERAL INFORMATION REGARDING A PSAP TEST CALL

ADDITIONAL INFORMATION REGARDING 9-3-3 SERVICE

 

 

CONFIGURING YOUR 9-1-1 SERVICES

 

SESSION BORDER CONTROLLERS (SBCs)

Bandwidth has two geographically redundant SBCs to send 911 calls to. Routing should be set up as primary/secondary or round-robin. Please reach out to your Implementation Specialist to obtain the specific IPs or open a support ticket at Bandwidth.com/support.

 

SIP PEERS

Bandwidth supports the provisioning of IP addresses for 9-1-1 routing. Ranges must be separated out, and DNS entries are not supported. By default, Bandwidth allows up to 10 IPs for sending 9-1-1 traffic. Additional IPs beyond that are subject to approval and additional charges.

NOTE:  To add new IPs, please reach out to your Implementation Specialist, if you are currently working with one. If not, please open a support ticket at Bandwidth.com/support.

 

SUPPORTED CODECS

Bandwidth only supports the G.711 u-law codec for 9-1-1. While a call may still traverse the Bandwidth SBC with a different codec, there is no guarantee that a codec other than G.711 u-law will be established properly, potentially causing the call to fail.

 

SUPPORTED PRIVACY TYPES

SIP peers can be configured with the following privacy types:

  • P-Asserted-Identity
  • Remote-Party-ID
  • P-Charge-Info

Bandwidth will automatically search the Remote-Party-ID  and From headers. If the P-Asserted-Identity option is set on the trunk group, Bandwidth will also search that header.   Headers are preferred in this order:

  1. P-Asserted-Identity (if P-Asserted-Identity option is set on the trunk group)
  2. Remote-Party-ID
  3. From

Bandwidth only supports one P-Asserted-Identity header, which must have a sip URI, not a tel URI.

Bandwidth also supports P-Charge-Info as a caller-identifying header.   You must notify your Implementation Specialist if want Bandwidth to use P-Charge-Info.   If P-Charge-Info is enabled, the caller identifier will be pulled from SIP headers in the following order:

  1. P-Charge-Info
  2. P-Asserted-Identity  (if P-Asserted-Identity option is set on the trunk group)
  3. Remote-Party-ID
  4. From

If no information is populated in any of the above fields, the call will receive a generic callback number and will be passed to the Emergency Call Center (ECC) for processing, unless you have requested that unprovisioned calls be denied.

Populating values in all privacy headers (P-Asserted-Identity, Remote-Party-ID, and P-Charge-Info) is not recommended.

 

MEDIA/AUDIO

Ports 1024-64000 UDP should be open for RTP Media.  If you require the Media IPs, please reach out to your Implementation Specialist.

 

OTHER SIP CONFIGURATIONS & SUPPORTED METHODS

  • SIP REFER is not supported; please use SIP REINVITE.
  • SIP registration should be turned off.
  • SIP authentication (username/password) should be disabled as it is not required
    and may hinder functionality.
  • OPTIONS messages are supported, but should not be sent more than once in a 60
    second period.

 

TESTING YOUR BANDWIDTH 9-1-1 CONFIGURATION

Once you’ve completed your Bandwidth 9-1-1 configuration, it’s time to test it. The steps below are all you need to properly test your setup and make sure you can successfully support 9-1-1 calls.

INTEROPERABILITY TESTING STEPS

Once all the technical requirements and setup are completed, testing for 9-1-1 functionality is an easy 3-step process. Please review the 3-step process and sample invites below before moving forward with sending Bandwidth production traffic.

 

Step One:  Provision a 9-1-1 Endpoint

Provision the endpoint with a valid address in the 9-1-1 Dashboard.

  

Step Two:  Make a 9-3-3 Call

Bandwidth provides a text-to-speech service for partial 9-1-1 testing. You may need to add 9-3-3 to your dial plan in order for the call to be made. This service, when called, will read back the telephone number and address that is provisioned in the 9-1-1 Dashboard.

The 9-3-3 test will perform the following validation checks:

  • The endpoint is properly provisioned
  • Basic interop to the Bandwidth SBC chosen
  • One-way audio

To call the 9-3-3 service, just send the SIP INVITE to 9-3-3 instead of 9-1-1.

 

Step Three:  Complete Live 9-1-1 Testing

Before completing, please confirm that you’re able to do the following:

  • Send a SIP INVITE to 9-3-3 and receive the automated recording that reads back the provisioned address.
  • Initiate a 9-1-1 call from a specific ANI. This ANI should be set in the From or P-Asserted-Identity fields in the SIP INVITE.
  • Failover to an alternate data center when you receive a SIP 410 response from a 9-1-1 SIP INVITE.

 

SIMULATED FAILOVER TESTING

This test will validate your system’s ability to successfully redirect failed calls to your secondary route.

During this test we will simulate a scenario in which your 9-1-1 call is sent to your primary route and will then fail with a SIP 410 response. When you receive a 410 response, you should send the SIP INVITE to the opposite data center.

To complete testing, simply make a call from the following ANIs:

  • If ATL is the primary, 15555558888
  • If DFW is the primary, 15555559999

Once you’re setup to do these things, you’re ready to migrate traffic.  Please notify us if you require any assistance with the migration of services.  

 

HANDLING SBC FAILURES

  • In the event of a live SBC failure, the Bandwidth SBC may respond with a 4xx, 5xx,
  • or 6xx SIP status, or will not respond at all (in the case of a hard-down situation).
  • The non-response or the error message must be handled appropriately on the customer side to fail over to the other functioning SBC.
  • The one exception is a 487 response, which is a normal response to you sending a CANCEL for the call. If you receive a 487, do not fail over to the alternate SBC.

 

SAMPLE INVITES

The sample invite is for a 9-1-1 call. A 9-3-3 INVITE is exactly the same, just replace “911” with “933”. See below for a description of 9-3-3 service.

 

INVITE sip:911@XXX.XX.XXX.XX.10:5060 SIP/2.0

From: <sip:5553211234@X.X.X.X:5060>;tag=9098.A419

To: <sip:911@XXX.XX.XXX.XX:5060>

Call-ID: 0014.4F26.94FB.4E45.909B.2603

CSeq: 8573 INVITE

Max-Forwards: 70

Via: SIP/2.0/UDP X.X.X.X:5060;branch=z9hG4bK4E45.9098.A4198573

Contact: <sip:911@XXX.XX.XXX.XX:5060>

Allow:INVITE,BYE,INFO,PRACK,CANCEL,ACK,OPTIONS,SUBSCRIBE,NOTIFY,REGISTER,REFER,UPDATE

Supported: timer,100rel

Content-Type: application/sdp

Content-Length: 195

 

v=0

o=- 23714 23714 IN IP4 X.X.X.X

s=-

c=IN IP4 X.X.X.X

t=0 0

m=audio 29740 RTP/AVP 0 101

a=rtpmap:101 telephone-event/8000

a=fmtp:101 0-15

a=ptime:20

a=sendrecv

 

TIPS FOR SUCCESSFUL 9-1-1 TEST CALLS

The PSAP testing instructions listed below are helpful suggestions for placing test calls to a PSAP. Test calls from an unprovisioned phone number are not permitted, unless specifically permitted ahead of time by your Bandwidth support team and may be charged for at the rate specified in the customer contract.

 

DOS AND DON’TS WHEN MAKING 9-1-1 TEST CALLS

  • It is a best practice to call the 10-digit non-emergency PSAP number that will be utilized in your testing and advise the 9-1-1 operator that you will be conducting 9-1-1 test calls in advance of any testing. Many larger PSAPs will request that you schedule testing with them during what are typically less busy hours. The non-emergency number of the PSAP can be obtained in the Bandwidth 9-1-1 Dashboard, while in the emergency endpoint. If you need assistance with this, please open a support ticket with us.
  • When calling 9-1-1, IMMEDIATELY state, “This is NOT an emergency; this is a test. Do you have a few minutes to review my information with me?”
  • If no, say “Thank you, goodbye” and immediately hang up. Try back at a less busy time, or schedule the test call as mentioned previously.
  • If yes, ask your questions quickly, and end the call.
  • Do expect the PSAP operators to be abrupt, as you could be blocking a life threatening call.
  • Do not call during the busy hour of lunch, or between 4:00pm-6:00pm in your local time zone or the location for which you are testing.
  • Try to call during off-hours such as 6:00am.

 

GENERAL INFORMATION REGARDING A PSAP TEST CALL

  • Ensuring that your 9-1-1 service testing is successful is extremely important. However, you should appreciate that Test Calls demand a 9-1-1 operator’s attention.  So, please remember that an actual emergency situation must take precedence over test calls.
  • PSAPs have limited trunking and stations.
  • Generally, PSAP turnover is high, which could result in staffing and training not being adequate.
  • Bandwidth has a comprehensive list of PSAP administrative contacts. If you have trouble with a specific PSAP, feel free to report it by opening a ticket with the support team. The support team will review the call recording, and clarify the situation with a supervisor or appropriate member of the PSAP team.

 

ADDITIONAL INFORMATION REGARDING 9-3-3 SERVICE

The 9-3-3 service is a courtesy text-to-speech service that Bandwidth offers as part of the 9-1-1 package. When an end user dials 9-3-3, it will play back the phone number and address provisioned in the dashboard. This service is used as part of the 9-1-1 testing performed during the onboarding process, prior to the live 9-1-1 calls, and is used primarily to test connectivity to the emergency IPs for 9-1-1 service. Secondarily, it tests to make sure the provisioned address is being broadcast.

As with any text-to-speech service, there may be parts that are not appropriately recognized and therefore skipped in the playback. The point to using the 9-3-3 service is to verify that:

  • Calls are reaching the SBCs
  • Some resemblance of the address provided in the Bandwidth 9-1-1 Dashboard is being represented

For example, if the 9-1-1 address entered is “123 N Main St, Ste 400, Denver Colorado 80205”, the 9-3-3 service would likely read back “123 Main, Denver Colorado 80205”. This would be considered a successful call. If it read back something entirely different, such as “2963 Stormy Ave, El Paso TX”, this would indicate a problem either with the 9-3-3 service or with the address in the Bandwidth 9-1-1 Dashboard.

The 9-3-3 service may be used any time (please limit calls to 1 call per minute). However it is a courtesy service and is not meant to be used as a fully functional address verification service. To verify a full address, it is best to check the provisioned address in the Bandwidth 9-1-1 Dashboard directly (or via an API call).

Still have questions? Contact your Implementation Specialist or open a ticket at Bandwidth.com/support.

 

 

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