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Job #: R-00023290
Location: O'Fallon, IL
Category: Network Administration and Ops
Schedule (FT/PT): Full Time
Travel Required: No
Shift: Day
Potential for Telework: No
Clearance Required: Secret
Referral Eligibility: Eligible
Group: Defense

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Job Description:

Global Information Grid (GIG) Service Management-Operations (GSM-O), a Defense and Intelligence Group of Leidos has an opening for a Network Gateway Engineer. Our customer is the Defense Information Systems Agency (DISA) located at Scott AFB, IL and acts as the provider of GIG/Defense Information System Network (DISN) services to the department of Defense (DoD) and national security organizations.
Principle Responsibilities:

  • Design, manage, and maintain a large, complex and highly resilient Network Infrastructure.
  • Experience with design and configuration of Cisco Voice platforms, Call Manager, Cisco routers, Cisco Firewalls, and Cisco switches. 
  • Manage all aspects of the Cisco Voice and Data network.
  • Must be organized, able to design and be document oriented in the engineering process, possess skills in Visio diagramming, and understand WAN/Wireless principals.
  • Implement and support BGP routing protocols.

Additional Duties and Responsibilities:

  • Configure route plans, route lists, device profiles, calling search spaces, and partitions.
  • Manage and configure Cisco routing/switching rules and firewall ACLs.
  • Design, manage and configure VMware vSphere ESXi, VMware vCenter, and VMware vSphere Client.
  • Provide analysis to network and distributed Firewall infrastructure. 
  • Design and maintain IPSec VPN infrastructure.
  • Demonstrable experience of advanced troubleshooting to isolate and diagnose network problems for routing, switching, security and large scale voice implementations. 

Basic Qualifications:

  • Bachelor's degree and 4-8  years of overall related experience. Additional experience, education and training may be considered in lieu of degree.
  • Currently possess DoD 8750 certification at IAT level II, Security+ce.
  • Currently possess an active Secret security clearance.

Preferred Qualifications:

  • Excellent knowledge of SIP signaling and call-flows.
  • Experience in SIP internetworking.
  • Experience with VMware vSphere ESXi, VMWare vCenter, and VMware vSphere Client.
  • Familiarity with IPSec implementation and troubleshooting.
  • Familiarity troubleshooting IPSLA statements.
  • Experience analyzing VLAN, routing, IP addressing and sub-netting.
  • Experience with ports and protocols.


External Referral Eligible

External Referral Bonus:


Potential for Telework:


Clearance Level Required:




Scheduled Weekly Hours:




Requisition Category:


Job Family:

Network Administration and Ops


Leidos is a Fortune 500® information technology, engineering, and science solutions and services leader working to solve the world's toughest challenges in the defense, intelligence, homeland security, civil, and health markets. The company's 33,000 employees support vital missions for government and commercial customers. Headquartered in Reston, Virginia, Leidos reported annual revenues of approximately $10.19 billion for the fiscal year ended December 28, 2018. For more information, visit

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