FEDERAL COMMUNICATIONS COMMISSION WASHINGTON, DC 20554 September 11, 2023 Shellie Blakeney Engineering and Technology Policy T-Mobile USA, Inc. 601 Pennsylvania Ave NW, Suite 800 Washington, DC 20004 Via Email: Shellie.Blakeney@T-Mobile.com Steve B. Sharkey Vice President, Government Affairs, Engineering and Technology Policy T-Mobile USA, Inc. 601 Pennsylvania Ave NW, Suite 800 Washington, DC 20004 Via Email: Steve.Sharkey@T-Mobile.com Re: Nationwide Wireless Emergency Alert Testing Dear Ms. Blakeney and Mr. Sharkey: Wireless Emergency Alerts (WEA) provide important and potentially life-saving information to the public in the event of a natural disaster or other critical situation. As a WEA participant, T-Mobile plays a key role in the alerting process, which is vital for emergency managers to help keep the public safe. Thank you for your voluntary participation in this important program. T-Mobile supported the 2022 WEA Performance Exercise, and the 2021 nationwide WEA test, by submitting answers to questions from the Public Safety and Homeland Security Bureau (PSHSB) related to its performance of the test. Building upon this history of collaboration, PSHSB now seeks T-Mobile’s cooperation in evaluating WEA’s performance during the upcoming nationwide WEA test, which is scheduled for Wednesday, October 4, 2023 at 2:18 p.m. EDT, with an alternate date on Wednesday, October 11, 2023, at the same time. The test will be conducted pursuant to the recently-granted waiver permitting Participating CMS Providers to participate in this test.1 PSHSB requests that T-Mobile provide, in writing, responses to the following inquiries regarding the performance of T-Mobile’s network during the test: 1. Did T-Mobile receive the test message and transmit it to its subscribers? a. At what time (to the closest millisecond, if available) did T-Mobile’s gateway/Cell Broadcast Entity receive the alert from FEMA’s Integrated Public Alert and Warning System (IPAWS)? 1 Wireless Emergency Alerts; Amendments to Part 11 of the Commission’s Rules Regarding the Emergency Alert System, DA 23-654, https://www.fcc.gov/document/pshsb-grants-waiver-nationwide-wea-test, (PSHSB Aug. 3, 2023). b. At what time (to the closest millisecond, if available) did T-Mobile transmit the alert to subscribers? 2. Did T-Mobile experience any difficulty receiving the test alert from FEMA IPAWS? For example, did T-Mobile experience any difficulty in receiving the test alert from FEMA IPAWS at its intended Alert Gateway and Cell Broadcast Center (CBC)? Did any of the Virtual Private Network (VPN) paths between the FEMA IPAWS gateway and T-Mobile fail during this test? a. Please provide a detailed description of the difficulty. b. For any of the above, what was the impact, if any, of the difficulty? For example, if T- Mobile received the test alert at an inactive or otherwise unanticipated CBC, what was the impact? c. What areas were affected (e.g., town/city, county, state, region)? How many subscribers were affected? 3. Did any elements of T-Mobile’s network not perform as expected during the test? For example, did any elements of T-Mobile’s network fail to log any anticipated attributes of the test alert message? Did any of T-Mobile’s indoor-based enterprise Radio Access Network (RAN) systems not transmit an alert during this test? a. For any of the above, please identify the affected system(s) and provide a detailed description of what happened and why. b. What, if any, was the impact on the timely delivery of the test alert message? What areas were affected (e.g., town/city, county, state, region)? How many subscribers were affected? 4. Did T-Mobile observe any instances in which more than one second elapsed between receipt of the test alert message from FEMA IPAWS and T-Mobile’s transmission of the test alert message to subscribers? a. If so, how long were the delays and what caused them? b. What area(s) were affected (e.g., town/city, county, state, region)? How many subscribers were affected? 5. Did T-Mobile experience any other complications or anomalies with its WEA capability during the nationwide test? a. If so, please provide a detailed description of the complications or anomalies, including the extent to which the issue(s) delayed or prevented receipt of the test alert message. b. What area(s) were affected (e.g., town/city, county, state, region)? How many subscribers were affected? 6. Describe any steps that T-Mobile has taken or is taking to address any complications or anomalies identified in questions 2-5, above. 7. Describe any other efforts that T-Mobile conducted to observe and evaluate WEA performance during the test, including any efforts to determine whether consumer handsets successfully displayed the alert. Please provide your responses, in writing, within two weeks of FEMA conducting its test, i.e., October 18, 2023, if FEMA conducts its test on October 4, 2023, and October 25, 2023, if FEMA conducts its test on October 11, 2023. The Bureau asks that T-Mobile please respond via the FCC’s Electronic Comment Filing System (ECFS) in PS Dockets 15-91, and 15-94.2 Comments may be filed electronically using the Internet by accessing ECFS: http://apps.fcc.gov/ecfs/. If you have any questions, please contact David Kirschner, at David.Kirschner@fcc.gov. Thank you for your continued efforts to ensure that the public receives life-saving WEA messages. Sincerely, Debra Jordan Chief Public Safety and Homeland Security Bureau cc: Nicole McGinnis, Deputy Chief, Public Safety and Homeland Security Bureau Austin Randazzo, Associate Chief, Public Safety and Homeland Security Bureau Rochelle Cohen, Communications Director, Public Safety and Homeland Security Bureau Erika Olsen, Acting Chief, Cybersecurity and Communications Reliability Division James Wiley, Deputy Chief, Cybersecurity and Communications Reliability Division David Kirschner, Attorney Advisor, Cybersecurity and Communications Reliability Division 2 Parties wishing to file materials with a claim of confidentiality should follow the procedures set forth in Section 0.459 of the Commission’s rules. Casual claims of confidentiality are not accepted. Confidential submissions may not be filed via ECFS but rather should be filed with the Secretary’s Office following the procedures set forth in 47 CFR § 0.459. Redacted versions of confidential submissions may be filed via ECFS. Parties are advised that the FCC looks with disfavor on claims of confidentiality for entire documents. When a claim of confidentiality is made, a public, redacted version of the document should also be filed. See, Enforcement Bureau Reminds Public that Requests for Confidentiality Must Cover Oly Material Warranting Confidential Treatment Under the Commission’s Rules, Public Notice, DA 20-579 (June 18, 2020).