Network Engineer
Network engineers design, implement, and troubleshoot the infrastructure that connects everything. This path covers the English for writing network architecture documentation, troubleshooting tickets, presenting network upgrade proposals, and communicating with cloud and security teams.
Topics covered
- Routing & switching
- BGP & WAN
- Network security
- SD-WAN & SASE
- Cloud networking
- Troubleshooting & monitoring
Vocabulary spotlight
4 terms every Network Engineer should know in English:
Border Gateway Protocol — the routing protocol that directs traffic between autonomous systems on the internet
"Our BGP peer went down during the maintenance window, causing a 3-minute outage."
Virtual Local Area Network — a logical network segment that isolates traffic within a physical network
"Finance traffic is isolated in a dedicated VLAN with strict ACLs."
The time delay for a packet to travel from source to destination
"End-to-end latency increased to 180ms after the cable cut rerouted traffic via the backup path."
Maximum Transmission Unit — the largest packet size that can be sent over a network path
"MTU mismatch between the VPN tunnel and the internal network caused packet fragmentation."
📚 Vocabulary Reference
Key terms organised by category for Network Engineers:
Fundamentals
Routing & Switching
WAN & SD-WAN
Security
Recommended exercises
Real-world scenarios you'll practise
- Writing a root cause analysis for a BGP session failure that caused a partial outage
- Presenting a SD-WAN migration proposal to IT management
- Documenting a new VLAN segmentation design for the security team
- Communicating network capacity constraints to an application team during project planning
🎯 Interview questions specific to this role
Practise answering these questions out loud — or in writing. Each question targets a real interviewer concern for Network Engineers.
- Explain the difference between a router and a Layer-3 switch.
- What is BGP and how is it different from OSPF?
- How would you troubleshoot a sudden increase in network latency?
- What are the advantages of SD-WAN over traditional WAN?
- How do you approach network security in a cloud-first organisation?