Sr. L4 Network Engineer/Architect

Seeking a Senior L4 Network Engineer / Architect with strong expertise in Cisco SD-WAN architecture, enterprise WAN design, MPLS routing, and fiber-based WAN/LAN integration. This role will be responsible for defining and leading the SD-WAN portion of the solution, including how Cisco SD-WAN will be designed, deployed, integrated, and supported across MPLS, Internet, broadband, LTE/5G, and other WAN transport options.

Cisco SD-WAN Architecture and Solution Definition Lead the design and definition of Cisco SD-WAN solutions for enterprise and mission-critical environments. Develop SD-WAN architectures using MPLS, Internet, broadband, LTE/5G, private-line, and hybrid WAN transport models. Define how Cisco SD-WAN overlays will operate across existing and future WAN underlays. Design SD-WAN control, data, and management plane architecture using Cisco SD-WAN components such as vManage, vBond, vSmart, and Cisco WAN Edge routers. Build and validate SD-WAN policies for application-aware routing, traffic steering, segmentation, path preference, SLA-based forwarding, failover, and resiliency. Define transport-side and service-side VPN designs, including how WAN edge devices connect into LAN, firewall, data center, and cloud environments. Lead SD-WAN migration planning from legacy WAN or MPLS-centric environments to modern Cisco SD-WAN architectures. Establish SD-WAN design standards, implementation templates, validation methods, and operational handoff documentation.

Cisco SD-WAN Deployment and Operations Configure, deploy, troubleshoot, and support Cisco SD-WAN environments using centralized templates, policies, and device-level configurations. Support Cisco SD-WAN edge platforms, including Cisco Catalyst 8000/8500, ISR, ASR, and other IOS-XE SD-WAN-capable platforms. Troubleshoot SD-WAN control connections, tunnel formation, BFD behavior, policy application, routing advertisements, NAT traversal, certificate issues, and overlay reachability. Validate application performance across multiple WAN transports using routing, SLA, QoS, and performance monitoring tools. Support high-risk SD-WAN cutovers, site migrations, circuit transitions, and production troubleshooting events. Partner with security, LAN, cloud, voice, application, and carrier teams to ensure SD-WAN designs meet business and technical requirements.

WAN, MPLS, and Routing Integration Design and support WAN environments that include MPLS, carrier Ethernet, Internet, broadband, private fiber, and hybrid transport models. Understand how Cisco SD-WAN operates over MPLS underlays, including transport VPN design, routing exchange, path selection, QoS treatment, and failover behavior. Support MPLS-related routing requirements, including L3VPN, L2VPN, VRF segmentation, PE/CE routing, route targets, route distinguishers, and carrier handoff models. Configure and troubleshoot advanced routing using BGP, OSPF, IS-IS, EIGRP, route redistribution, route filtering, prefix lists, route maps, communities, and routing policies. Work with carriers and service providers to validate circuit delivery, MPLS routing handoffs, CE/PE demarcation, SLA performance, and escalation of provider-side issues. Ensure WAN routing designs support SD-WAN overlay requirements, application performance, segmentation, and resiliency objectives.

WAN/LAN Edge and Physical Handoff Integration Define how WAN services terminate into customer environments, including routers, switches, firewalls, optical handoffs, and LAN aggregation points. Validate WAN/LAN interface designs involving routed handoffs, VLAN tagging, trunking, port channels, VRFs, firewall zones, and segmentation boundaries. Understand how fiber-based services are delivered into a site, including carrier demarcation, cross-connects, patching, optics, transceivers, and handoff types. Work with field teams and providers to validate fiber paths, patch schedules, port assignments, light levels, media types, and physical connectivity. Troubleshoot physical and Layer 1/Layer 2 issues involving fiber, optics, dirty connectors, incorrect transceivers, speed/duplex mismatches, VLAN tagging, port configuration, and cabling errors. Ensure SD-WAN edge devices are properly integrated with upstream carrier services and downstream LAN, firewall, and data center infrastructure.

• • Experience as a Senior Technical Leader who understands how to build and operate Cisco SD-WAN environments over complex underlays, including MPLS and carrier Ethernet services. While deep MPLS knowledge is important, this role is

not limited to traditional MPLS engineering. Must be able to define how the SD-WAN overlay should operate, how it integrates with existing WAN and LAN environments, and how it supports routing, segmentation, performance, resiliency, security, and operational requirements.

• • Understands how WAN services physically enter a site, including carrier handoffs, fiber termination, optics, demarcation points, WAN edge routers, firewalls, and LAN aggregation infrastructure. The role requires hands-on technical depth,

architectural judgment, troubleshooting discipline, and the ability to guide engineering teams through complex design, implementation, migration, and escalation scenarios.

• • Understands physical reality behind the design how the carrier circuit enters the building, how fiber is terminated and patched, how the handoff reaches the WAN edge router, and how that router connects into the LAN or security stack.
• • Able to define how SD-WAN overlays are built across MPLS and Internet transports, how routing and segmentation should work, how applications should be steered across available paths, how failover should behave, and how the WAN edge

connects into the broader LAN, firewall, and data center environment. 10+ years of enterprise or service provider network engineering experience, with significant hands-on responsibility for WAN, routing, and production network environments. Strong hands-on experience designing, deploying, and troubleshooting Cisco SD-WAN solutions. Strong understanding of Cisco SD-WAN architecture, including overlay/underlay design, vManage, vBond, vSmart, WAN edge routing, templates, policies, and centralized management. Experience building Cisco SD-WAN solutions over MPLS, Internet, broadband, LTE/5G, and hybrid WAN transports. Strong routing expertise with BGP, OSPF, IS-IS, EIGRP, route redistribution, route filtering, route maps, prefix lists, communities, and policy-based routing. Working knowledge of MPLS services, including L3VPN, L2VPN, VRFs, PE/CE routing, QoS, and carrier handoff models. Hands-on experience with Cisco WAN edge and routing platforms such as Cisco Catalyst 8000/8500, ASR, ISR, or equivalent enterprise/service provider platforms. Strong understanding of how WAN circuits physically terminate into customer environments, including carrier handoffs, fiber, optics, routers, switches, firewalls, and LAN aggregation devices. Ability to troubleshoot across multiple layers, including physical fiber, carrier services, routing, SD-WAN overlays, QoS, firewall integration, and application performance. Experience leading technical cutovers, site migrations, WAN transformations, circuit turn-ups, and high-risk maintenance windows. Ability to create clear technical documentation, diagrams, implementation plans, validation plans, and operational handoff materials. Strong communication skills with the ability to explain Cisco SD-WAN, WAN, routing, and fiber concepts to technical teams, project teams, and client stakeholders.

TECHNICAL SKILLS: Cisco SD-WAN Cisco SD-WAN architecture and design vManage, vBond, vSmart, and WAN Edge platforms SD-WAN templates and centralized policies Application-aware routing SLA-based path selection Transport-side and service-side VPNs Segmentation and traffic steering SD-WAN over MPLS, Internet, broadband, and LTE/5G SD-WAN migration and cutover planning SD-WAN troubleshooting and operational support

WAN and Routing Enterprise and hybrid WAN architecture MPLS L3VPN and L2VPN concepts BGP, OSPF, IS-IS, EIGRP VRFs, route targets, route distinguishers Route redistribution and filtering QoS and traffic engineering Dual-carrier and multi-transport WAN designs Carrier handoff and CE/PE integration

WAN/LAN and Fiber Integration WAN edge and LAN edge integration Routed and switched handoffs VLAN tagging, trunking, and port channels Firewall and LAN aggregation connectivity Fiber handoffs and carrier demarcation SFP/SFP+/QSFP optics Dark fiber, lit fiber, and carrier Ethernet Cross-connects, patching, and optical validation OTDR and light-level test interpretation

Cisco Platforms Cisco Catalyst 8000/8500 series Cisco ISR and ASR platforms Cisco IOS-XE and IOS-XE SD-WAN Cisco Catalyst switching Cisco Nexus experience preferred