Installation guide

Packet filtering 30-16
Chapter 30: Understanding Wave Data Networking
Wave Global Administrator Guide
As an example, you could create an environment where only web browsing was permitted, by
filtering out all protocols except for DNS and HTTP. To do this, the following filters can be put
into place on the WAN connection to the Internet, with the filters set to drop all except those
listed below.
PPTP filtering
In some environments, a network may only be used for tunneling, but not for actual traffic. For
example, a branch office may use PPTP to tunnel through the Internet to headquarters, but may
not use it for anything else. More commonly, the interface has protocol filters in place, and you
can allow PPTP traffic, allowing home users to tunnel into the company’s network.
Caution: On the Advanced TCP/IP Protocol properties windows of the Microsoft
Windows Network control applet, there is an Enable PPTP Filtering option. Do not
select this option.
13 Time stamp request
14 Time stamp reply
15 Information request
16 Information reply
17 Address mask request
18 Address mask reply
Protocol filters for Web browsing (drop all except those listed below)
Direction Filter Type Protocol Direction Port
Input Protocol UDP Source port 53
Input Protocol TCP Source port 80
Output Protocol UDP Destination port 53
Output Protocol TCP Destination port 80
ICMP message types
Type Description
Release 2.0
September 2010