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When do i have to use a gre over ipsec tunnel? i have heard that when i m using a routing protocol and vpn site to site i need a

i have configured a network with ospf and a vpn site to site without gre tunnel and it works very well. I want to know, when do i have to use gre tunnel over ipsec

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Hi josedilone19 GRE is used

Hi josedilone19

 

GRE is used when you need to pass Broadcast or multicast traffic.  That's the main function of GRE.

Generic Routing Encapsulation (GRE) is a protocol that encapsulates packets in order to route other protocols over IP networks

 

However there are some other important aspect to consider: 

In contrast to IP-to-IP tunneling, GRE tunneling can transport multicast and IPv6 traffic between networks
GRE tunnels encase multiple protocols over a single-protocol backbone.
GRE tunnels provide workarounds for networks with limited hops.
GRE tunnels connect discontinuous sub-networks.
GRE tunnels allow VPNs across wide area networks (WANs).

 

-Hope this helps -

 

 

 

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Silver

Hi josedilone19 GRE is used

Hi josedilone19

 

GRE is used when you need to pass Broadcast or multicast traffic.  That's the main function of GRE.

Generic Routing Encapsulation (GRE) is a protocol that encapsulates packets in order to route other protocols over IP networks

 

However there are some other important aspect to consider: 

In contrast to IP-to-IP tunneling, GRE tunneling can transport multicast and IPv6 traffic between networks
GRE tunnels encase multiple protocols over a single-protocol backbone.
GRE tunnels provide workarounds for networks with limited hops.
GRE tunnels connect discontinuous sub-networks.
GRE tunnels allow VPNs across wide area networks (WANs).

 

-Hope this helps -

 

 

 

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