Sergio Gaona Email and Phone Number

AT&T E911 Resolution Center

AT&T Technology Operations -Tier 2 network surveillance and analysis of over 100 EMS/OSS servers & disk arrays in 8 different locations across the U.S.-Part of a 24X7 staff of 20 delivering network server and tech support for Ericsson, Cisco, Alcatel-Lucent, Nortel, Fujitsu element management systems supporting hundreds of employees and contractors.-Support provided for AT&T employees & contractors includes user access, password reset & application support.-Provided remote hardware support of our platforms by dispatching & working with local site technicians to resolve hardware issues in our servers & storage arrays.-In 2017 our team met our 5 hour MTTR goal for critical tickets at 93% & our 120 hour MTTR goal for major tickets at 92%.-Worked with Tier 3 support to identify root cause and implement corrective action. Server uptime was 99.99% for 2017.-Part of a team of 3 who developed an internal wiki for the purpose of providing our group easy access to troubleshooting tips and procedures saving our teammates time troubleshooting common problems.AT&T Network Operations-Tier 1 network surveillance and analysis of Mobility Network Reliability Center Core switching equipment and EMS/OSS servers.-Part of a 24X7 staff delivering mobility network switch & tech support.-Provided network surveillance and analysis for mobility core switch equipment for Nortel DMS, Alcatel Lucent, Nokia, Ericsson Mobility Switch Center, Media Gateway and peripheral equipment and implementation of tier 1 support for Element Management System servers.-Provided technical troubleshooting and leadership required to recover from the most complex network problems by working with local site technicians & engaging Tier 2 support as needed.-Perform root cause analysis, implement resolution or work-arounds. Test and implement tier 2, vendor/IT fixes or design changes.

Network Reliability Center SONET Maintenance Technician- Work SONET trouble tickets for several fiber optic multiplexor types such as; Nortel, Fujitsu, Adtran, Cisco, Lucent, Tellabs & Alcatel.- Locate trouble, dispatch field technicians via internal systems & work with field technicians on tickets dispatched to resolve fiber optic issues such as loss of signal, bit errors & node failures. - Use circuit documents to help isolate trouble.

Network Reliability Center DMS 100/200 Surveillance & Maintenance- Received trouble tickets through internal systems on Nortel DMS telephony switches. - Perform remote maintenance & dispatched field technicians as needed. - Assist field technicians with card replacement procedures using approved documentation.

Communication Link Maintenance- Restored communication links to various network equipment types such as, Nortel & Adtran multiplexers, CBX500 ATM switches, Titan & DACS Digital Cross connect System(DCS) machines, TSG3800 clocks & other equipment. - Ensured our technicians could communicate to the equipment for maintenance & provisioning work.System Administration- Performed installation, maintenance, upgrades & troubleshooting of Sun Solaris UNIX, HP-UX and Windows based servers & UNIX based workstations- Local support for Network Operations Center of nearly 500 employees - Installed SecurID access software on newly built servers & performed yearly security audits.- Administered user access to servers and performed database backups as scheduled. - Led project teams for BPON, Fiber To The Premise(FTTP) & Wavesmith server installation & turn-up.- Maintained user access records for 50+ servers.

Network Operations Center- Performed trunk provisioning, test & turn up on 4ESS Tandem switch- Performed message & E911 trunk provisioning, test & turn up Lucent 5ESS telephone switches.