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Defense, Government Contracting, Cybersecurity, IT Services, Aerospace, Healthcare Technology

Enterprise Voice Engineer III

IllinoisOnsiteFull Time$73,450–$132,775 /yrPosted 1 month agoVisa sponsorship available

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Required skills

  • DoD 8750
  • Security+ CE
  • Cisco Unified Communications Manager
  • CUCM
  • Cisco Unity
  • CUBE
  • Oracle Session Border Controller
  • SBC
  • Avaya Aura Application Server
  • SIP

Nice to have

  • SRTP
  • G.711
  • G.729
  • DTMF
  • Avaya Aura soft switches
  • voice media gateway

Role summary

Leidos is seeking an Enterprise Voice Engineer III to support the Defense Information Systems Agency (DISA) by providing sustainment, maintenance, and problem/change management for secure and reliable DISA Voice Services. The role involves maintaining a complex IP voice and video infrastructure, managing and troubleshooting voice, video, and data networks, and performing system maintenance and capacity planning. Key responsibilities include configuring voice routing elements, Cisco or Juniper network devices, and supporting distributed firewalls. The engineer will analyze and resolve complex technical issues related to SIP signaling, call flows, and remote site connectivity, requiring strong documentation and diagramming skills. A Secret security clearance and DoD 8750 IAT Level II certification (e.g., Security+ CE) are required, along with experience in Cisco voice platforms and SIP internetworking.

Our customer, the Defense Information Systems Agency (DISA), provides, operates, and assures command and control of the Defense Information System Network (DISN) services to its customers, the department of Defense (DoD) and national security organizations. This position directly supports the DISA-provided capabilities and services.

The Leidos Digital Modernization Sector/Global Solutions Management-Operations II (GSMO-II) contract has an opening for an Enterprise Voice Engineer. The Enterprise Voice Engineer will perform sustainment, maintenance, Problem and Change management services to help ensure secure, reliable, and uninterrupted availability of DISA Voice Services.

Responsible for performing and training the team on the following duties:

• Perform engineering tasks to maintain a large, complex and highly resilient IP voice and video communications infrastructure.
• Manage, configure, troubleshoot and assure service supporting all aspects of a voice, video and data network. Must be organized, document oriented, possess skills in diagramming, and understand WAN principals.
• Perform system maintenance, support capacity planning activities and complete configuration change actions and documentation efforts.
• Configure and implement calling search spaces, route plans, route partitions, route lists and device profiles.
• Configure Cisco or Juniper routing and switching devices.
• Support distributed firewall infrastructure.
• Develop technical policy, work instructions and reporting in support of an enterprise IP telephony network.
• Analyze and resolve complex technical problems utilizing foundational knowledge of SIP signaling and call-flows.
• Analyze and resolve remote site registration, signaling and media problems.
• Validate change requests and ensure accuracy.
• Perform fault analysis and configuration of voice subscribers, call handlers and call routing rules.
• Perform fault analysis and configuration of Cisco and or Juniper routing and switching rules.

Basic Qualifications:

• Currently possess DoD 8750 certification at IAT level II, Security+ CE or equivalent to meet requirement.
• Experience with one or multiple Cisco, Avaya or Oracle voice platforms including Cisco Unified Communications Manager (CUCM), Cisco Unity, Cisco Unified Border Element (CUBE), Oracle Session Border Controller (SBC) and Avaya Aura Application Server.
• Expertise in SIP internetworking signaling and call flow.
• Demonstrable experience of advanced fault analysis to isolate and diagnose network problems for routing, switching, security and large scale voice implementations.
• Currently possess an active Secret security clearance.

Preferred Qualifications:

• Working knowledge of Secure Real-Time Transport Protocol (SRTP) including associated G.711 and G.729 codecs and Digital Tone Multi Frequency (DTMF).
• Experience with Cisco Unified Communications Manager and or Avaya Aura soft switches.
• Experience with Oracle SBCs and other voice media gateway appliances.
• Experience supporting distributed firewall infrastructure.
• Experience creating/supporting IPSec MPLS VPN infrastructure.
• Experience implementing and supporting BGP routing protocols.
• Experience designing, configuring and troubleshooting QoS classification, marking and prioritization of network traffic (voice, critical applications, etc.).
• Familiarity with IPSec implementation and troubleshooting.

Required Experience & Education:

Requires BS and 4-8 years of prior relevant experience or Masters with 2-6 years of prior relevant experience. (Or equivalent combination of education and/or experience.)

GSMO

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares.

Original Posting:

September 21, 2026

For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range:

Pay Range $73,450.00 - $132,775.00

The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.

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