Ip-In-Ip Decapsulation - Cisco 6000 Series Configuration Manual

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C H A P T E R
Configuring IP-in-IP Decapsulation
This module describes how to configure IP-in-IP Decapsulation.
• IP-in-IP Decapsulation, on page 143

IP-in-IP Decapsulation

Encapsulation of datagrams in a network is done for multiple reasons, such as when a source server wants to
influence the route that a packet takes to reach the destination host. The source server is also known as the
encapsulation server.
IP-in-IP encapsulation involves the insertion of an outer IP header over the existing IP header. The source
and destination address in the outer IP header point to the end points of the IP-in-IP tunnel. The stack of IP
headers are used to direct the packet over a predetermined path to the destination, provided the network
adminstrator knows the loopback addresses of the routers transporting the packet. This tunneling mechanism
can be used for determining availability and latency for most network architectures. It is to be noted that the
entire path from source to the destination does not have to be included in the headers, but a segment of the
network can be chosen for directing the packets.
The following illustration describes the basic IP-in-IP encapsulation and decapsulation model.
Interface and Hardware Component Configuration Guide for Cisco NCS 6000 Series Routers, IOS XR Release 6.4.x
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