Network security engineer

CrossTech is seeking a Network Security Engineer on an ongoing basis to design, implement, and maintain secure, reliable, and high-performance network infrastructure across the enterprise. The ideal candidate will bring strong technical expertise in routing, switching, firewalls, and network security, along with hands-on experience managing hybrid and cloud-connected environments. This role ensures the integrity, stability, and protection of network systems by combining deep networking knowledge with security best practices.

The Network Security Engineer will work closely with infrastructure, cloud, and cybersecurity teams to deliver robust, scalable network solutions that meet business and compliance requirements.

Key Responsibilities

• Design, configure, and manage enterprise LAN, WAN, MAN, and wireless networks with a focus on security, performance, and availability
• Implement, maintain, and troubleshoot firewalls, VPNs, load balancers, and intrusion prevention systems (IPS)
• Manage and optimize network access controls, routing protocols, and traffic management policies
• Collaborate with cybersecurity teams to develop and enforce network security standards, segmentation, and compliance controls
• Support and manage network connectivity for hybrid and multi-cloud environments (AWS, Azure, GCP)
• Perform capacity planning, performance analysis, and root-cause troubleshooting for network incidents
• Develop and maintain network documentation, including topology diagrams, configuration standards, and technical procedures
• Evaluate emerging network technologies and recommend enhancements to improve performance and security posture
• Participate in on-call rotation and provide off-hours support as needed
• Work cross-functionally with project managers and technical teams to deliver network infrastructure projects on time and within scope

Required Qualifications

• Bachelor's degree in Electrical Engineering, Computer Science, or related field — or equivalent experience
• 5+ years of experience in network engineering and network security within enterprise environments
• Expertise in Cisco technologies including Nexus, Catalyst, ISR, and ASR platforms
• Strong understanding of routing protocols (EIGRP, BGP, OSPF, HSRP, VRRP, GLBP) and Layer 2/3 networking principles
• Hands-on experience with firewalls (Cisco ASA/NGFW, Palo Alto, or Fortinet), VPN (IPSec/SSL), and F5 Load Balancing (LTM/ASM)
• Proficiency in wireless technologies, DNS/DHCP/IPAM, and network monitoring tools
• Strong knowledge of QoS, packet capture, and network performance analysis
• Excellent troubleshooting, analytical, and documentation skills
• Ability to work independently, manage multiple priorities, and communicate effectively with technical and business teams

Preferred Qualifications

• Professional certifications such as CCNP, CCNA Security, F5-CTS, or equivalent
• Experience with cloud networking (AWS, Azure, or GCP) and hybrid network architectures
• Knowledge of VoIP, multicasting, and optical networking
• Familiarity with Gigamon, Radius/TACACS, and advanced network monitoring platforms

Compensation

Competitive compensation and comprehensive benefits

Location

Philadelphia, PA