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Career Roadmaps · Network

Career roadmap

Network Engineer

Design and run the connectivity everything else depends on, increasingly through code rather than a console.

Time
6-10 months part-time
Entry bar
No prior experience required; this is a genuine entry route into tech.
Stages
5 · 25 topics
0/25 studied0%
All roadmaps

Before you start Network

  • Willingness to learn protocols in detail
  • A lab: physical kit, GNS3, or Containerlab
  • Basic Linux

Protocol fundamentals

6-8 weeks · 0/5 topics

Networking rewards depth. Surface knowledge fails the first troubleshooting question.

  1. Every troubleshooting conversation is structured around layers. Fluency here is mandatory.

    • OSI and TCP/IP layers in practice
    • Encapsulation and MTU
    • Ethernet frames and ARP
    • Following a packet end to end

  2. Subnetting under time pressure is still asked in interviews and exams.

    • IPv4 subnetting and VLSM
    • IPv6 addressing and transition
    • CIDR and route summarisation
    • NAT types and their consequences

  3. Layer 2 problems are the ones that take down whole floors.

    • VLANs, trunking and 802.1Q
    • Spanning tree and loop prevention
    • Link aggregation
    • MAC learning and broadcast domains

  4. OSPF and BGP are the two protocols every network interview covers.

    • Static routing and administrative distance
    • OSPF areas and LSA types
    • BGP path selection and attributes
    • Route filtering and redistribution

  5. DNS and DHCP failures look like everything being broken at once.

    • DNS resolution, records and caching
    • DHCP and relay behaviour
    • NTP and why time matters
    • TLS and certificate chains

BuildA lab topology with VLANs, routing between them, and a documented packet walk from host to host.

Troubleshooting and operations

5-6 weeks · 0/5 topics

The daily job: something is slow or down, and everyone thinks it is the network.

  1. Being fast with the right tool is what separates competent from slow.

    • ping, traceroute and MTR interpretation
    • tcpdump and Wireshark filters
    • Interface counters and errors
    • Flow data: NetFlow and sFlow

  2. Interviews score the method as much as the answer.

    • Layer-by-layer isolation
    • Divide and conquer on the path
    • Distinguishing loss, latency and jitter
    • Proving it is not the network

  3. Bandwidth is rarely the problem. Buffers, queues and MTU usually are.

    • Latency, jitter, loss and their causes
    • Queueing, buffering and bufferbloat
    • QoS classification and shaping
    • MTU, fragmentation and PMTUD blackholes

  4. Network monitoring is moving from SNMP polling to streaming telemetry.

    • SNMP and its limitations
    • Streaming telemetry and gNMI
    • Synthetic probes and path monitoring
    • Capacity trending

  5. Network changes are high blast radius and usually happen at night for a reason.

    • Change windows and rollback plans
    • Pre and post change validation
    • Configuration backup and diffing
    • Documenting topology accurately

BuildBreak your own lab deliberately five times and write a diagnostic runbook for each failure.

Cloud and modern networking

5-6 weeks · 0/5 topics

The growth half of the role. Cloud networking is where the new jobs are.

  1. Same concepts, different names, and some genuinely different constraints.

    • VPC, subnets and route tables
    • Security groups vs network ACLs
    • Transit gateways and peering
    • Private endpoints and service networking

  2. Connecting the data centre to the cloud is a large share of enterprise network work.

    • IPsec VPN design
    • Direct Connect / ExpressRoute
    • BGP over hybrid links
    • Overlapping address space problems

  3. Branch connectivity moved to software-defined overlays across most enterprises.

    • SD-WAN architecture and controllers
    • VXLAN and EVPN in the data centre
    • Overlay vs underlay troubleshooting
    • Path selection policy

  4. Segmentation and zero trust are where network and security roles overlap.

    • Firewall rule design and hygiene
    • Microsegmentation
    • Zero trust network access
    • DDoS mitigation

  5. Kubernetes networking questions now appear in network engineering interviews.

    • Pod and service networking
    • CNI plugins and dataplanes
    • Ingress and load balancer integration
    • Debugging across the overlay

BuildBuild hybrid connectivity between a lab network and a cloud VPC, entirely from Terraform.

Network automation

5-6 weeks · 0/5 topics

The skill that separates a network engineer in 2026 from one in 2010.

  1. Scripting is now an expected interview topic for network roles.

    • Netmiko and NAPALM
    • Parsing device output reliably
    • REST and NETCONF APIs
    • Error handling and idempotency

  2. Ansible dominates network automation in enterprises.

    • Network modules and inventories
    • Templating configs with Jinja2
    • Idempotent config pushes
    • Dry-run and diff modes

  3. Automation without a source of truth just automates the drift.

    • NetBox as intended state
    • IPAM and DCIM discipline
    • Generating config from data
    • Reconciling actual vs intended

  4. Validating a change before it reaches production kit.

    • Containerlab and virtual topologies
    • Pre-deployment validation tests
    • Batfish configuration analysis
    • Pipeline for network changes

  5. Cloud network work is Terraform work.

    • Terraform for cloud networking
    • Module design for network resources
    • State and blast radius
    • Drift detection

BuildAutomate configuration of your whole lab from a source of truth, with validation tests in CI.

Certification and interviews

4-6 weeks · 0/5 topics

Networking is one of the few fields where certification is a genuine hiring filter.

  1. CCNA remains the recognised baseline; CCNP is the differentiator.

    • CCNA exam domains
    • Hands-on lab practice
    • CCNP Enterprise path
    • Vendor-neutral alternatives

  2. The combination of CCNA plus a cloud networking cert is unusually marketable.

    • AWS Advanced Networking
    • Azure Network Engineer
    • Google Network Engineer
    • Mapping on-premises concepts to cloud

  3. Expect subnetting on the spot and a detailed packet-walk question.

    • Subnetting without a calculator
    • Walk a packet through the network
    • BGP path selection explained
    • Troubleshooting scenario questions

  4. Design a campus, data centre or cloud topology with redundancy and growth.

    • Redundancy and failure domains
    • Addressing plan and summarisation
    • Scaling and growth headroom
    • Cost and vendor considerations

  5. Outage stories and change discipline are what this round is really probing.

    • A major outage you resolved
    • A change that went wrong and what you changed
    • Working with application teams
    • Documenting for the next engineer

BuildPass CCNA, then a cloud networking certification, and publish your lab topology repository.

Network tools on your CV

  • Wireshark
  • Containerlab / GNS3
  • Ansible
  • Python / Netmiko
  • NetBox
  • Terraform
  • Batfish
  • Cisco / Arista / Juniper

What Network employers ask to see

  • A lab topology repository others can reproduce
  • A network automation project driven from a source of truth
  • CCNA plus a cloud networking certification
  • A troubleshooting write-up with packet captures

Named in demand surveys with very low unemployment. Cloud did not remove the need — it moved it, and engineers who can do both physical and cloud networking are scarce.

Content last reviewed 2026-08-31. Guidance only — no institute or paid placement is endorsed anywhere in this book.