Senior Network Engineer

Castalia Systems; United States; On-site; USD 110,000 - 160,000; Full time

Benefits offered by this job

Medical dental and vision coverage

401k matching

generous PTO paid holidays

professional training opportunities

pet insurance

Job summary

Castalia Systems is seeking a Senior Network Engineer for a 100% onsite role in Largo, Florida. The position focuses on implementing network security and information assurance solutions, maintaining DoD‑grade networks, and supporting enterprise voice and data infrastructure.

The role requires Cisco CUCM/Unity, VOIP platforms, STIG compliance, and collaboration with cybersecurity teams to ensure secure, reliable operations in a defense context.

Qualifications

• Bachelor's degree with 12 months relevant experience or 6 years if no degree.
• DoD 8570 IAT Level II certification required/maintained.
• Security or CISSP preferred.
• Strong networking and security systems knowledge.
• Excellent written and verbal communication.
• Ability to work independently with limited oversight.
• Analytical and problem-solving skills.

Responsibilities

• Configure, administer and maintain CUCM clusters in enterprise and classified environments.
• Manage Unity Connection voicemail systems and related call flows.
• Configure dial plans, SIP trunks, and voice gateway infrastructure.
• Provide Tier III support for voice routing, signaling and QoS issues.
• Develop upgrade runbooks, patches, and maintenance schedules.

Skills

DoD 8570 IAT II

Networking fundamentals

Security best practices

VoIP troubleshooting

Independent worker

Education

Bachelor's degree

Tools

Juniper SRX/EX routers

CUCM/UCCX

Job description

Job Type Full Time Workplace Type Onsite Clearance TSSCI Must be a US Citizen

Benefits

• Medical dental and vision coverage
• 401k matching
• generous PTO paid holidays
• professional training opportunities
• pet insurance to ensure your furry friends are cared for too

Job Summary

Castalia Systems is seeking a Senior Network Engineer for a position in Largo Florida. Due to the applicable duties this position requires 100% onsite employee status. The Network Engineer position implements network security and information assurance solutions for program and development systems based upon system level requirements architecture models and engineering design documents using a defense in depth approach on trusted products. This position will involve maintenance installation testing and general support for network infrastructure. The ability and know how to do basicadvanced troubleshooting including testing during and after implementation. A solid understating of networking fundamentals is required and how these fundamental technologies are used in a LAN MAN or WAN architecture.

Roles and Responsibilities

• Configure, administer and maintain Cisco Unified Communications Manager CUCM clusters supporting enterprise and classified environments
• Manage and maintain Cisco Unity Connection voicemail systems including user provisioning, call handlers, automated attendants and voicemail integrations
• Configure and support dial plans, route patterns, route groups, route lists, SIP trunks, device pools, partitions and calling search spaces
• Administer and troubleshoot voice gateways, session border controllers and VoIP infrastructure
• Provide Tier III technical support troubleshooting complex voice call routing, registration signaling and voice quality issues
• Design, implement and maintain hunt pilots, hunt lists, line groups, call queuing and call coverage solutions to optimize call distribution and operational workflows
• Configure, manage and support Meet Me conferencing services, conference bridge resources and collaboration platforms
• Plan, coordinate and execute CUCM and Unity Connection upgrades, patches and lifecycle management activities
• Develop upgrade runbooks, rollback procedures, testing plans and maintenance schedules to ensure successful system implementations
• Deploy, configure and integrate UniFi FX solutions within enterprise communications environment
• Support migration planning, testing, validation and production cutover activities for voice and collaboration modernization initiatives
• Implement and maintain DISA Security Technical Implementation Guide STIG compliance for Cisco Unified Communications platforms and associated virtual appliances
• Perform vulnerability remediation, security hardening, compliance validation and support cybersecurity audits, inspections and accreditation activities
• Maintain secure communications environments in accordance with DoD organizational and cybersecurity requirements
• Develop and maintain engineering diagrams, configuration standards, operational procedures, disaster recovery plans and technical documentation
• Create documents and defend system change requests while ensuring configuration management compliance
• Conduct root cause analysis, incident response activities and corrective actions to improve system reliability and performance
• Collaborate with cybersecurity, network infrastructure and business stakeholders to implement and support enterprise communication services
• Gather, analyze and report system performance metrics to support operational readiness, capacity planning and continuous improvement initiatives
• Provide technical guidance and mentorship to junior engineers and support personnel
• Contribute to strategic modernization efforts and the design architecture and enhancement of enterprise voice and collaboration platforms

Required Qualifications

• Bachelors degree and 12 months of relevant professional work experience excluding internships
• In absence of a degree 6 years of relevant experience is required
• Must be able to attain and maintain a DoD 8570 IAT Level II certification
• Security or CISSP preferred
• A strong understanding and knowledge of computer network and security systems
• Good interpersonal and communication skills
• Strong analytical critical thinking and problem solving skills
• Ability to work well independently under limited oversight be self directed and able to prioritize work

Preferred Qualifications

• Experience with Juniper SRX EX series routers and switches
• Experience deploying security solutions for DoD networks
• Experience with multi platforms like Windows UNIX LINUX
• Understanding of network engineering fundamentals including OSI layers IP addressing sub netting TCPIP stack VLANs DHCP etc
• Willingness to learn new technologies and applications as required
• Demonstrated experience implementing computer security
• Ability to adapt both an offensive and defensive mindset to support securing information systems
• Ability to quickly switch tasks based on changing priorities
• Strong writing speaking and interpersonal skills along with the ability to take initiative and work independently without supervision
• Ability to work with an extremely risk adverse customer and their policies

Physical Requirements

• Work Environment: Normal Office environment
• Travel: As needed

Company Description

Castalia Systems is a proven business partner providing mission critical solutions to the Federal Government. We provide cutting edge solutions from Securing and Managing Data to Systems Engineering and Development. Castalia Systems is a pioneer in Artificial Intelligence Design and Application. With our vast knowledge of our customers needs and relevant technology our team is able to bring successful solutions to every mission. We are one upping our competitors by providing premium IT solutions and platforms with cutting edge technology so its so evident when you compare us with anyone.

Disclaimer

Castalia Systems is an equal employment opportunity and affirmative action employer and strives to comply with all applicable laws prohibiting discrimination based on race color creed sex sexual orientation age national origin or ancestry physical or mental disability veteran status marital status HIV positive status as well as any other category protected by federal state or local laws. All such discrimination is unlawful and all persons involved in the operations of the company are prohibited from engaging in this type of conduct.