Why might an IP datagram be encapsulated in another IP datagram?

Question

I've seen references to this technique, but struggle to understand the purpose. What possible use might exist for such a construct?

MattH · Accepted Answer · 2011-04-13 14:37:55Z

1

In order to create a network tunnel.

In order to remotely monitor traffic.

answered Apr 13, 2011 at 14:37

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Comments

Pete Wilson · Accepted Answer · 2011-04-13 14:42:04Z

1

Tunneling? Implement a private protocol? Certainly many, many other uses.

answered Apr 13, 2011 at 14:42

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slandau · Accepted Answer · 2011-04-13 14:37:48Z

It just took me a quick Google to come across an article explaining everything you need to know about the why and the how's of this:

This doesn't answer the question. The document refers to encapsulation of layers of protocol. Not an IP datagram within another IP datagram.