[pptp-server] GRE protocol - security

[Kurt Vlaminck]

Hello,

I am new to this mailing list so apologise if this questions has already 
been treated.

I saw that you need to open the GRE protocol in both ways 
(outgoing/incoming) when implementing a PPTP server behind a firewall. Is't 
this a security issue as you have to open ports into both directions?
I need to be sure when opening these ports on the firewall that this 
protocol on port 47 is completely safe.

Pse comments are more than welcome.

                  _____________________________________
                 |           BELGACOM Skynet  n.v./s.a.           |
                 |                     Kurt Vlaminck                        |
                 |           Senior Internet Field Engineer            |
	     _|        Kol. Bourgstraat 124, Evere 1140          | _
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             / / |         E-mail: kurt at skypro.be                       | \ \
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