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Community Member

vpn tunnels - transport or tunnel mode on pix

We have routers that run gre tunnels and pixs that then ipsec encrypt before the packet gets to our remote sites. I would like to know if, you can run transport mode for vpn site to site connectivity as transport mode just encrypts the payload rather then the whole packet and only adds a few bytes.

Secondly, Is there anything to watch out for as far as applications are concerned in transport mode.

Thirdly, is there any advantage for voip packets when running in transport mode, thinking that the whole packet does not get encrypted, hence faster delivery i.e smaller packets. We will be having qos in place as well.


Re: vpn tunnels - transport or tunnel mode on pix

Since you will be having QoS on youyr network and since only Transport mode supports QoS, you can rule out Tunnel mode.

Community Member

Re: vpn tunnels - transport or tunnel mode on pix

I don't think the pix supports qosing as that is where I would be creating the ipsec tunnels. Only the router would do the GRE encapsulation.

Secondly, any advantage for voice packets as per my previous message ?

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