WHAT IS GRE TUNNELS & HOW TO CONFIGURE ?
WHAT IS GRE TUNNELS & HOW TO CONFIGURE ?
GRE is a tunneling protocol that provides connectivity to a wide
variety of network-layer protocols by encapsulating and
forwarding packets over an IP-based network. GRE was
originally created to provide transport for non-routable legacy
protocols such as Internetwork Packet Exchange (IPX) across
an IP network and is now more commonly used as an overlay
for IPv4 and IPv6. GRE tunnels have many uses. For example,
they can be used to tunnel traffic through a firewall or an ACL
or to connect discontiguous networks, and they can even be
used as networking duct tape for bad routing designs. Their
most important application is that they can be used to create
VPNs