Level 3 Network Engineer

About the Role We are seeking an experienced Level 3 Network Engineer to join our IT Infrastructure team at our Central Islip office. In this role, you will be responsible for managing, designing, implementing, and troubleshooting complex network solutions with a focus on Cisco and Meraki technologies. You will act as the escalation point for Level 1 and 2 network support, ensure high availability and performance of network infrastructure, and participate in strategic network planning. Key Responsibilities Serve as the subject matter expert (SME) for all Cisco and Meraki networking systems. Design, configure, and deploy enterprise-level LAN, WAN, and WLAN solutions. Monitor and optimize network performance using tools such as Cisco DNA Center, Meraki Dashboard, and Solar Winds. Respond to and resolve escalated network incidents and problems; lead root cause analysis. Maintain documentation for network architecture, topologies, and configurations. Collaborate with cross-functional teams on infrastructure projects and security initiatives. Assist in network upgrades, migrations, and expansion projects. Provide mentorship and technical guidance to junior network staff. Perform regular firmware upgrades, patch management, and compliance checks. Travel to remote offices and data centers for installations, audits, and troubleshooting (10-20%).Required Qualifications 5+ years of hands-on experience in network engineering. Strong expertise in Cisco networking technologies (Catalyst, ISR/ASR, ASA/Firepower, Nexus).In-depth experience with Cisco Meraki products (MX, MR, MS).Proven experience with Layer 2 and Layer 3 networking, VLANs, routing protocols (OSPF, BGP, EIGRP), VPNs, NAT, QoS.Solid understanding of network security principles and firewalls. Familiarity with cloud networking (Azure/AWS) and SD-WAN solutions is a plus. Strong analytical and troubleshooting skills. Preferred CertificationsCCNP (Cisco Certified Network Professional) required. Meraki CMNA or ECMS certification is a plus. CCIE (optional but highly desirable).Work Environment This is a full-time onsite role in our Central Islip office. Some regional travel (10-20%) to support remote sites and projects. Flexible schedule and after-hours support may be required during critical deployments or outages.