The Everything Feed - All Packet Pushers Pods N4N026: What Is a Tunnel?
May 15, 2025
Dive into the fascinating world of data networking as the hosts unravel the concept of tunnels, explaining how one packet can travel inside another. They debunk common myths while exploring tunneling methods like IPsec and VXLAN, shedding light on their vital roles in securing data. The discussion also highlights the nuances of encapsulation, contrasting MPLS with segment routing. Using a clever package delivery analogy, they rethink the terminology around tunneling, emphasizing the importance of content over the method of delivery.
AI Snips
Chapters
Transcript
Episode notes
Defining Network Tunnels
- A tunnel is when you put one packet inside another to carry it across a network.
- It can encapsulate packets or complete Ethernet frames for transport, not limited to IP packets only.
Use Tunnels for Security
- Use tunnels to secure traffic across untrusted networks by encrypting packets between endpoints.
- VPNs commonly employ tunneling to safely connect separate private networks over the public internet.
Tunnel Metaphor Limits
- Intermediate routers only forward the outer encapsulating packet, unaware of the inner payload.
- This explains why tunnels aren't direct paths but rather encapsulated journeys through many hops.