I just deleted several hundred proxies from our proxy database. We currently have over three thousand working proxies in our proxy list.

The definition of what is a “working proxy” is one that comes up frequently. A person may try twenty proxies — and discover that none of them work for him. Are those proxies then not “working proxies”?

Not exactly. Those proxies still work fine – they have just been blocked by the content filter (such as WebSense) at their location.

Sometimes one of these users will say “Why don’t you delete this proxy from the list, because it is now blocked?” It’s not that simple, for two reasons:

• There are dozens of content filtering software packages, each with its own databases
• Each organization can define their own filter rule sets and individual site filters

The proxy might be blocked by SmartFilter, but allowed by WebSense. Or, it might be blocked only by one particular school.

There is simply no way for us to tell what proxies are blocked from what networks.

The best strategy for proxy users to follow is to use new proxies, as they are less likely to be blocked by content filters.