Network Security EngineerCrossTech 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 ResponsibilitiesDesign, configure, and manage enterprise LAN, WAN, MAN, and wireless networks with a focus on security, performance, and availabilityImplement, maintain, and troubleshoot firewalls, VPNs, load balancers, and intrusion prevention systems (IPS)Manage and optimize network access controls, routing protocols, and traffic management policiesCollaborate with cybersecurity teams to develop and enforce network security standards, segmentation, and compliance controlsSupport and manage network connectivity for hybrid and multi-cloud environments (AWS, Azure, GCP)Perform capacity planning, performance analysis, and root-cause troubleshooting for network incidentsDevelop and maintain network documentation, including topology diagrams, configuration standards, and technical proceduresEvaluate emerging network technologies and recommend enhancements to improve performance and security postureParticipate in on-call rotation and provide off-hours support as neededWork cross-functionally with project managers and technical teams to deliver network infrastructure projects on time and within scopeRequired QualificationsBachelor's degree in Electrical Engineering, Computer Science, or related field — or equivalent experience5+ years of experience in network engineering and network security within enterprise environmentsExpertise in Cisco technologies including Nexus, Catalyst, ISR, and ASR platformsStrong understanding of routing protocols (EIGRP, BGP, OSPF, HSRP, VRRP, GLBP) and Layer 2/3 networking principlesHands-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 toolsStrong knowledge of QoS, packet capture, and network performance analysisExcellent troubleshooting, analytical, and documentation skillsAbility to work independently, manage multiple priorities, and communicate effectively with technical and business teamsPreferred QualificationsProfessional certifications such as CCNP, CCNA Security, F5-CTS, or equivalentExperience with cloud networking (AWS, Azure, or GCP) and hybrid network architecturesKnowledge of VoIP, multicasting, and optical networkingFamiliarity with Gigamon, Radius/TACACS, and advanced network monitoring platformsCompensation Competitive compensation and comprehensive benefitsLocation Philadelphia, PA