L2/L3 Network Technical Support Engineer – Broadband
• Location: Redmond, WA (Onsite 5 days per week)
• Type: Long term contract
• Work Authorization: U.S. Citizen or Green Card
Role Overview
We are looking for an experienced L2/L3 Network Technical Support Engineer to provide postlaunch technical support for a broadband service provider’s network and services. The role will
be responsible for diagnosing and resolving complex network issues across broadband access,
IP, transport, and service layers.
The ideal candidate is a hands-on network engineer who can dig deep into network incidents,
isolate the specific fault domain, analyze network behavior and traffic, identify root causes, and
drive issues through to resolution. This role requires strong troubleshooting skills and the ability
to work across multiple network domains, including access, aggregation, routing, IP services,
and customer connectivity.
The engineer will work closely with NOC, network engineering, operations, architecture, service
assurance, vendors, and other technical teams to resolve production issues and improve
network stability after launch.
Key Responsibilities - L2/L3 Network Troubleshooting
• Provide L2/L3 technical support for production broadband network issues following service
launch.
• Troubleshoot complex incidents involving customer connectivity, service degradation, packet
loss, latency, routing, reachability, and network performance.
• Analyze issues across the network stack to determine whether the problem originates in the
access, aggregation, transport, IP, routing, service, or customer-premises domain.
• Perform detailed fault isolation and identify the specific network element, interface, route,
configuration, protocol, or service component contributing to an incident.
• Troubleshoot Layer 2 technologies such as VLANs, QinQ, Ethernet, ARP, MAC learning, STP,
and related access/aggregation technologies.
• Troubleshoot Layer 3 technologies including IPv4/IPv6, BGP, OSPF/IS-IS, routing policies, VRFs,
DHCP, DNS, NAT, and IP connectivity.
• Analyze packet captures, network logs, alarms, counters, routing tables, interface statistics,
and telemetry to identify root causes.
• Perform hands-on troubleshooting using CLI and network management/monitoring tools.
• Validate suspected issues by testing network paths, interfaces, routes, configurations, and
service dependencies.
• Support troubleshooting of broadband subscriber connectivity and service issues, including
DHCP/IP address assignment, authentication, routing, DNS, CGNAT, and Internet reachability, as
applicable to the network architecture.
• Correlate customer-impacting symptoms with network-level events and infrastructure faults.
Incident & Problem Management
• Own or contribute to resolution of complex L2/L3 production incidents.
• Work with NOC teams to investigate incidents that cannot be resolved through standard
operational procedures.
• Determine the appropriate escalation path and engage network engineering, architecture,
vendors, or other technical teams when required.
• Drive incidents toward resolution rather than simply escalating them.
• Conduct root-cause analysis for recurring or high-impact network problems.
• Develop and document troubleshooting procedures, known-error articles, and operational
runbooks.
• Identify opportunities to improve network monitoring, alarms, automation, and operational
processes based on recurring issues.
• Support post-incident reviews and provide technical recommendations to prevent recurrence.
Network Operations & Engineering Collaboration
• Collaborate with network engineering teams on complex production issues and configuration
changes.
• Validate network changes and troubleshoot issues following software upgrades, configuration
changes, migrations, or new service launches.
• Support network equipment and service troubleshooting across routers, switches, broadband
access equipment, aggregation devices, and IP infrastructure.
• Work with equipment and technology vendors to investigate hardware, software, protocol,
and interoperability issues.
• Provide technical input into network design improvements based on production support
experience.
• Participate in planned maintenance and change activities when required.
• Support troubleshooting during critical incidents and service-impacting events.
Required Technical Skills
• Strong hands-on experience troubleshooting Layer 2 and Layer 3 networks in a production
environment.
• Strong understanding of TCP/IP, Ethernet, VLANs, ARP, DHCP, DNS, IPv4/IPv6, routing, and IP
connectivity.
• Experience troubleshooting routing protocols such as BGP and OSPF/IS-IS.
• Experience with VRFs, routing policies, NAT/CGNAT, QoS, and IP service delivery.
• Ability to use network device CLI to investigate configuration and operational state.
• Strong understanding of packet flows and ability to trace a problem hop-by-hop through the
network.
• Experience using packet capture and analysis tools such as Wireshark/tcpdump.
• Experience interpreting network monitoring data, logs, alarms, interface counters, routing
tables, and telemetry.
• Ability to distinguish between customer/device issues, access-network issues, transport
issues, IP/routing issues, and application/service issues.
• Strong analytical and problem-solving skills with the ability to work from symptoms to root
cause.
Broadband Experience
Experience in a broadband service provider environment is strongly preferred, including
exposure to technologies such as:
• Fiber/FTTH broadband
• PON technologies such as GPON/XGS-PON
• OLT/ONT
• Broadband access and aggregation networks
• BNG/BRAS
• DHCP and IP address management
• RADIUS/AAA
• CGNAT
• Broadband subscriber management
• VLAN/QinQ
• MPLS/Segment Routing, where applicable
• IPv6 and dual-stack broadband
• DNS
• Network monitoring and service assurance platforms
Desired Experience
• 5+ years of experience in network engineering, network operations, or technical support.
• Experience supporting large-scale production IP/broadband networks.
• Experience working in a 24x7 operational environment and supporting critical incidents.
• Experience troubleshooting multi-vendor network environments.
• Experience with network automation or scripting using Python, Ansible, or similar
technologies is a plus.
• Experience with network telemetry, observability, and service assurance platforms is a plus.
• Relevant networking certifications such as CCNA/CCNP, JNCIA/JNCIP, or equivalent practical
experience are desirable.
What Success Looks Like
The successful candidate will be able to take an ambiguous production issue such as:
"Customers in a specific region are experiencing intermittent Internet connectivity." and
independently work through the network to determine:
• Which customers/services are affected
• Where the affected traffic enters the network
• Whether the issue is isolated to access, aggregation, transport, routing, or IP services
• Which network devices/interfaces/routes are involved
• What network behavior is abnormal
• What evidence supports the suspected root cause
• What corrective action is required
• Whether the issue has been fully resolved after the change
The role requires someone who does not stop at identifying that "the network is down" or
escalating the ticket, but can investigate the underlying network behavior and identify the
specific technical failure.
Key Attributes
• Strong troubleshooting mindset
• Hands-on and technically curious
• Comfortable working from incomplete information
• Able to analyze problems systematically and follow the traffic/data path
• Strong understanding of networking fundamentals
• Comfortable using CLI, packet captures, logs, and monitoring tools
• Persistent in getting to root cause
• Able to communicate complex technical findings clearly
• Comfortable working under pressure during customer-impacting incidents
• Strong collaboration skills across NOC, engineering, architecture, vendors, and operation