[plug] re; Network filtering

[Colin Rothnie]

On Friday, 15 October 1999 17:14, Jon L. Miller [SMTP:jlmiller at wantree.com.au] 
wrote:
> Does anyone know of a product that can filter undesirable web pages, etc
> using Linux as the Internet gateway.

I have used Custodian with some success.  It doesn't rely on regular 
expressions, but uses a black-list algorithm.  It even comes with a 30,000 
entry sex-based black list (encrypted).

The program works as a "helper" for Squid, so users must be using Squid as 
their proxy.  The program requires plenty of RAM and reasonable CPU power.  On 
a 486/66 with 16 Mb of ram Custodian caused a 9 second delay on every requested 
object, but on a 300 Mhz Pentium II with 128 Mb there was no appreciable 
overhead.

Some things to watch for if using Custodian;
- I don't think it prevents objects already in the cache from being served up.
- You can easily add new domains or sites to the blocklist with the programs 
supplied with Custodian.
- It would be relatively simple to write a CGI program that would allow 
"non-administrator" types to add sites to the blocklist, keeping in mind 
however, that the site is possibly already in the cache.
- You can also use Custodian in "white list" mode, although I haven't tried 
this.

Hope this helps.
Colin Rothnie.