Did you complete this GRE Tunneling lab? Here are the answers (Part 1):
GNS3 Topology: https://goo.gl/8hdwoa
GNS3 course: https://goo.gl/8J77nz

For lots more content, visit http://www.davidbombal.com – learn about GNS3, CCNA, Packet Tracer, Python, Ansible and much, much more.

You need to know GRE for the CCNA exam.

Generic Routing Encapsulation (GRE) is a tunneling protocol developed by Cisco Systems that can encapsulate a wide variety of network layer protocols inside virtual point-to-point links over an Internet Protocol network.

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