Senior Network Engineer

TEKsystems; Denver (CO); On-site; USD 91,000 - 129,000; Full time

Job summary

TEKsystems in Denver, CO seeks an experienced Network Security Engineer specializing in NAC and Cisco ISE to support authentication modernization and secure access across a large enterprise. The role focuses on migrating to 802.1X and certificate-based authentication, coordinating with PKI, network and security teams, and delivering engineering outcomes.

This contract position is onsite in Denver with competitive hourly compensation.

Qualifications

• 5+ years of hands‑on enterprise Cisco ISE experience.
• Experience designing and troubleshooting distributed Cisco ISE deployments, including PAN, PSN, and MnT nodes.
• Strong knowledge of wired/wireless 802.1X, MAB, RADIUS, and network authentication.
• Experience with Cisco switching, enterprise network infrastructure, and authentication troubleshooting.
• Understanding of certificate‑based authentication, PKI integration, and certificate lifecycle management.
• Experience supporting enterprise security engineering deployments and complex technical migrations.
• Ability to work independently and communicate effectively across technical and non‑technical teams.
• Experience with Cisco Secure Network Analytics (SNA), NetFlow/IPFIX, behavioral analytics, and network threat visibility, as specified in the official requisition.

Responsibilities

• Engineer, configure, troubleshoot, and support Cisco ISE infrastructure across distributed enterprise environments.
• Support large-scale migration from MAC Authentication Bypass (MAB) and other weaker authentication methods toward stronger 802.1X authentication.
• Coordinate certificate provisioning, deployment, renewal, and authentication dependencies with PKI and infrastructure teams.
• Support network asset discovery, classification, authentication policy validation, and migration readiness.
• Partner with network engineering, operations, security, and application teams to execute engineering initiatives.
• Incorporate security requirements, architecture documentation, threat models, and technical standards into solution development.
• Perform integration, regression, and performance testing, analyze results, and troubleshoot root causes.
• Identify security control gaps and implement remediation plans.
• Document deployment procedures, technical dependencies, operational requirements, and implementation results.
• Provide technical guidance to project managers and cross-functional stakeholders.

Skills

Cisco ISE

Network Access Control

Cisco switches

Skyhigh

Routers

NetFlow

Stealthwatch

OSPF

VLAN

VRF

Wireshark

Tools

Cisco ISE

PKI

SNA

Job description

Description

Network Security Engineer Network Access Control (NAC)

Position Overview

Seeking an experienced Network Security Engineer to support multiple enterprise security engineering initiatives focused on Network Access Control (NAC), authentication modernization, and secure network access.

The engineer will serve as a technical subject matter expert supporting Cisco Identity Services Engine (ISE), with an emphasis on improving authentication standards across a large enterprise environment. Responsibilities include supporting the migration of network-connected assets from weaker authentication methods toward stronger 802.1X and certificate-based authentication.

Key Responsibilities

Engineer, configure, troubleshoot, and support Cisco ISE infrastructure across distributed enterprise environments.

Support large-scale migration from MAC Authentication Bypass (MAB) and other weaker authentication methods toward stronger 802.1X authentication.

Coordinate certificate provisioning, deployment, renewal, and authentication dependencies with PKI and infrastructure teams.

Support network asset discovery, classification, authentication policy validation, and migration readiness.

Partner with network engineering, operations, security, and application teams to execute engineering initiatives.

Incorporate security requirements, architecture documentation, threat models, and technical standards into solution development.

Perform integration, regression, and performance testing, analyze results, and troubleshoot root causes.

Identify security control gaps and implement remediation plans.

Document deployment procedures, technical dependencies, operational requirements, and implementation results.

Provide technical guidance to project managers and cross-functional stakeholders.

Skills

cisco ise, network access control, cisco switches, skyhigh, switches, router, netflow, stealthwatch, ospf, vlan, vrf, wireshark

Top Skills Details

cisco ise,network access control,cisco switches,skyhigh,switches,router

Additional Skills & Qualifications

Required Qualifications

5+ years of hands‑on enterprise Cisco ISE experience.

Experience designing and troubleshooting distributed Cisco ISE deployments, including PAN, PSN, and MnT nodes.

Strong knowledge of wired/wireless 802.1X, MAB, RADIUS, and network authentication.

Experience with Cisco switching, enterprise network infrastructure, and authentication troubleshooting.

Understanding of certificate‑based authentication, PKI integration, and certificate lifecycle management.

Experience supporting enterprise security engineering deployments and complex technical migrations.

Ability to work independently and communicate effectively across technical and non‑technical teams.

Experience with Cisco Secure Network Analytics (SNA), NetFlow/IPFIX, behavioral analytics, and network threat visibility, as specified in the official requisition.

Desired Qualifications

Cisco Catalyst, Nexus, and wireless infrastructure.

TCP/IP, BGP, OSPF, VLANs, VRFs, and Wireshark.

Insider threat detection, data exfiltration analysis, and threat hunting.

Skyhigh Secure Web Gateway and proxy policy exposure.

Experience in large, regulated financial services environments.

Experience Level

Expert Level

Job Type & Location

This is a Contract position based out of Denver, CO.

Pay and Benefits

The pay range for this position is $80.00 - $80.00/hr.

Individual compensation offered for this position within this range will depend on many factors, including qualifications, skills, relevant experience, job knowledge, geographic location, internal equity, and other pertinent job‑related factors.

Eligibility requirements apply to some benefits and may depend on your job classification and length of employment. Benefits are subject to change and may be subject to specific elections, plan, or program terms. If eligible, the benefits available for this temporary role may include the following: Medical, dental & vision Critical Illness, Accident, and Hospital 401(k) Retirement Plan Pre‑tax and Roth post‑tax contributions available Life Insurance (Voluntary Life & AD&D for the employee and dependents) Short and long‑term disability Health Spending Account (HSA) Transportation benefits Employee Assistance Program Time Off/Leave (PTO, Vacation or Sick Leave)

Job Type & Location

This is a Contract position based out of Denver, CO.

Application Deadline

This position is anticipated to close on Nov 13, 2026.

Workplace Type

This is a fully onsite position in Denver,CO.

About TEKsystems

We're partners in transformation. We help clients activate ideas and solutions to take advantage of a new world of opportunity. We are a team of 80,000 strong, working with over 6,000 clients, including 80% of the Fortune 500, across North America, Europe and Asia. As an industry leader in Full-Stack Technology Services, Talent Services, and real‑world application, we work with progressive leaders to drive change. That's the power of true partnership. TEKsystems is an Allegis Group company.

The company is an equal opportunity employer and will consider all applications without regards to race, sex, age, color, religion, national origin, veteran status, disability, sexual orientation, gender identity, genetic information or any characteristic protected by law.

About TEKsystems and TEKsystems Global Services

Were a leading provider of business and technology services. We accelerate business transformation for our customers. Our expertise in strategy, design, execution and operations unlocks business value through a range of solutions. Were a team of 80,000 strong, working with over 6,000 customers, including 80% of the Fortune 500 across North America, Europe and Asia, who partner with us for our scale, full‑stack capabilities and speed. Were strategic thinkers, hands‑on collaborators, helping customers capitalize on change and master the momentum of technology. Were building tomorrow by delivering business outcomes and making positive impacts in our global communities. TEKsystems and TEKsystems Global Services are Allegis Group companies. Learn more at TEKsystems.com.

The company is an equal opportunity employer and will consider all applications without regard to race, sex, age, color, religion, national origin, veteran status, disability, sexual orientation, gender identity, genetic information or any characteristic protected by law.

San Francisco Fair Chance Ordinance: Pursuant to the San Francisco Fair Chance Ordinance, for all positions located in the city and county of San Francisco, we will consider for employment qualified applicants with arrest and conviction records.

Massachusetts Lie Detector: It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.

Use of Artificial Intelligence (AI): We may use Artificial Intelligence (AI) to support parts of our hiring process, including sourcing, screening, and evaluating candidates. AI helps assess applications and qualifications, but final decisions are made by our hiring team. By applying, you acknowledge and agree that your application may be reviewed using AI tools.