Senior Network Engineer: DoD Onsite Voice & Security

Castalia Systems; Largo (FL); On-site; USD 90,000 - 130,000; Full time

Benefits offered by this job

Medical coverage

Dental coverage

Vision coverage

401k matching

Generous PTO

Paid holidays

Professional training

Pet insurance

Job summary

Castalia Systems in Largo, Florida is seeking aSenior Network Engineer to design, deploy, and maintain secure network solutions for DoD-aligned environments. This onsite role requires strong expertise in CUCM, Unity, VoIP, and defense-in-depth security.

You will lead fault isolation, upgrades, and network modernization efforts, collaborate across cybersecurity and infrastructure teams, and ensure STIG compliance and reliable voice and data services.

Qualifications

• Bachelor’s degree required or 6 years of relevant experience
• DoD 8570 IAT Level II certification (Security+ or CISSP preferred)
• Strong networking, security, and computer systems knowledge
• Ability to work independently with minimal supervision

Responsibilities

• Configure, administer, and maintain CUCM clusters supporting enterprise environments
• Manage Cisco Unity Connection voicemail systems and integrations
• Configure dial plans, route patterns, SIP trunks, and call routing components
• Administer and troubleshoot voice gateways and VoIP infrastructure
• Provide Tier III technical support for voice and signaling issues
• Plan and execute CUCM/Unity upgrades and lifecycle activities
• Develop runbooks, testing plans, and maintenance schedules
• Collaborate with cybersecurity and network teams to support enterprise voice and collaboration

Skills

Strong communication skills

Analytical thinking

Problem solving

Self-directed

Education

Bachelor’s degree

6 years of relevant experience

DoD 8570 IAT Level II certification

Tools

CUCM

Cisco Unity Connection

VoIP infrastructure

Security/STIG

Job description

Castalia Systems in Largo, Florida is seeking aSenior Network Engineer to design, deploy, and maintain secure network solutions for DoD-aligned environments. This onsite role requires strong expertise in CUCM, Unity, VoIP, and defense-in-depth security.

You will lead fault isolation, upgrades, and network modernization efforts, collaborate across cybersecurity and infrastructure teams, and ensure STIG compliance and reliable voice and data services.