The GRE protocol [RESOLVED]

I am trying to clean out rules that I dont understand what they do.

I have a rule (that was there when I installed the latest version) that says

“Allow IP out from Any IP to Any IP where the protocol is GRE”

A search on the web on GRE gave this:

GRE (Generic Routing Encapsulation) is used to send information where the sender and the receiver use different protocols. This is done by encapsulationg the information to be sent using GRE.

‘(GRE) A protocol which allows an arbitrary network protocol A to be transmitted over any other arbitrary network protocol B, by encapsulating the packets of A within GRE packets, which in turn are contained within packets of B.’ - Quote from the Free Online Dictionary of Computing

The most common use of the GRE protocol is by Microsoft’s VPN. The Generic Route Encapsulation (GRE) protocol is used in conjunction with Point-to-Point Tunneling Protocol (PPTP) to create virtual private networks (VPNs) between clients or between clients and servers.

I assume I can safely delete this rule unless I use specific VPN software. Am I right? Or is this rule nessesary for day to day use of the internet? Or maybe this rule does not do any harm?

If you’re not using tunnelling it won’t hurt to leave it there. If your PC has nothing to respond to any unsolicited inbound request, it would die a natural death.

ewen :slight_smile:

Thanks for your reply. I´ll leave it there then since it doesnt do any harm, maybe I´ll have use for that rule someday :slight_smile: