Senior Network Security Engineer

**Role:** Sr Network Security Engineer
**Location:** Suitland, MD - 100% onsite, 5 days/week

Long Term Contract.

**About the role**

The agency is moving off its legacy ForeScout CounterACT NAC/NAM platform and onto Cisco ISE as its new access-control system. This engineer will configure and manage Cisco ISE across the environment - AAA services, wired/wireless 802.1X authentication, device administration, and posture checks - and will support the ForeScout-to-ISE migration, troubleshoot access issues, and strengthen identity-based access controls as part of the agency's Zero Trust modernization work.

**Must-Haves (candidates must meet ALL of these - please confirm before submitting)**

- ship (Public Trust position)
- Public Trust eligible; active Public Trust is a plus
- Willing and able to work 100% onsite in Suitland, MD, 5 days/week
- 8 years of total network/security experience
- 4 years of hands-on Cisco ISE experience
- Bachelor's degree in IT, Cybersecurity, or a related field (or equivalent experience)

**Strong Plus**

- Hands-on experience with ForeScout CounterACT (NAC/NAM policies, device classification, access workflows) - this is a major differentiator given the migration project
- Cisco ISE deployed on SNS-3715 appliances in a clustered, high-availability setup
- Experience with Cisco 9800 Wireless LAN Controllers (guest/registration portals, wireless onboarding)
- CCNP Security, CCIE Security, or Cisco ISE Specialist certification
- Prior technical leadership in a large federal/government environment; familiarity with NIST 800-53, FISMA

Tria Federal is seeking a Senior Network Security Engineer to support the agency as it moves
away from its legacy ForeScout CounterACT NAC/NAM system and adopts Cisco Identity
Services Engine (ISE) as the new accesscontrol platform. The engineer will help configure and
manage Cisco ISE across the environment, handling AAA services, wired and wireless 802.1X
authentication, device administration, and posture checks for users and devices.
This role also supports the agency's modernization work by improving authentication
processes, updating ISE policies, and strengthening identity-based access controls. The engineer
will troubleshoot access issues, refine policy designs, and help ensure users and devices can
connect securely and reliably as the organization completes its transition from ForeScout to
Cisco ISE.

Basic Requirements
Senior Network Security Engineer responsible for designing, configuring, monitoring,
and troubleshooting Cisco ISE as a NAC/NAM platform, including TACACS /RADIUS
services, device administration policies, and wired/wireless 802.1X authentication.
Experience working with Cisco ISE deployed on Cisco SNS3715 appliances, preferably in
a twonode clustered, highavailability setup.
Understanding of ForeScout CounterACT, including legacy NAC/NAM policies, device
classification, and access workflows, to support the migration to Cisco ISE.
Experience providing general wireless network support, including basic troubleshooting,
controller interactions, and wireless access workflows.
Handson experience integrating Cisco ISE with Active Directory (AD) and LDAP, including
identity lookups, groupbased policy decisions, and directorybased authentication.
Eight (8) years of experience in a large government organization with five (5) years in
technical leadership, including four (4) years implementing and troubleshooting Cisco
ISE with expertise in:

o Authentication and authorization policies (RADITACACS )
o 802.1X/EAP methods for wireless and wired access
o Device profiling, posture checks, and endpoint compliance
o Certificatebased authentication (EAPTLS) and PKI integration
o AAA integrations for switches, appliances, firewalls, and wireless controllers
Experience supporting Cisco ISE integrations with Cisco 9800 Wireless LAN Controllers,
including guest/registration page redirection and wireless onboarding.

Experience migrating legacy NAC, RADIUS, or device authentication systems into Cisco
ISE while aligning with Zero Trust principles.
Four (4) years of experience supporting identitycentric or Zero Trust architectures with
strong knowledge of segmentation, certificate management, and endpoint posture
controls.

Solid understanding of telecommunications, network security, and Zero Trust best
practices.
Strong communication skills with the ability to explain Cisco ISE, NAC/NAM, and AAA
concepts to both technical and nontechnical audiences.
Bachelor's degree in Information Technology, Cybersecurity, or a related field.
Preferred certifications: Cisco CCNP Security, Cisco ISE Specialist, or similar
identity/security certifications.
Responsibilities
Troubleshoot and resolve Cisco ISE issues across RADIUS, TACACS , 802.1X, device
administration, and endpoint authentication.
Deploy, configure, and maintain Cisco ISE running on two clustered Cisco SNS3715
appliances, ensuring high availability and consistent policy enforcement.
Support the agency's migration from ForeScout CounterACT to Cisco ISE, including
reviewing legacy ForeScout policies, device groups, and access rules and mapping them
into ISE policy sets.

Provide general wireless support, including basic troubleshooting, wireless access
workflows, and coordination with wireless infrastructure teams.
Configure and support Cisco ISE integrations with Cisco 9800 WLCs, including
guest/registration portals, wireless onboarding, and policydriven access control.
Integrate and maintain Cisco ISE with Active Directory (AD) and LDAP, including identity
lookups, groupbased authorization, and directorybased authentication workflows.
Deploy, configure, and maintain Cisco ISE components, including:
o Policy Sets, Authorization Profiles, and Authentication Rules
o TACACS device administration
o 802.1X for wired and wireless networks
o Profiling, posture, and compliance policies
o Certificatebased authentication and PKI integrations
Monitor security events using ISE logs, syslog, and performing root cause analysis for
authentication and access issues.
Manage identity integrations, enforce security policies, and tune configurations to
support Zero Trust and improve user experience.

Perform routine health checks, upgrades, migrations, and document changes through
SOPs, engineering designs, and implementation procedures.
Work closely with engineering, operations, and compliance teams while mentoring
junior staff and contributing to knowledge sharing efforts.