Sunday, January 28, 2007


Ask maintains a blacklist of IP addresses

Someone at should realize that IP addresses are dynamically given out by ISPs to their clients (potentially) each time they connect - so blacklisting "clients" by IP addresses is not a very smart thing to be doing.

I recently found that the IP address I was now allocated was somehow on Ask's blacklist, and that instead of getting Ask's search engine, all I got was a page saying:

Your client does not have permission to access this site.

Please refer to the terms of service page.( and Syndication).

If you feel that you have received this response in error, please send an email to Before sending this email, please refer to our terms of service page, accessible at the url provided above.

Please copy and paste the information below into the body of the email.

I'm not sure if emailing that address is an automated system to remove the IP address from the blacklist - you can probably spot that the text they ask to be included in the body of the email is simply the hex representation of the client's IP address, (repeated 3 times for some reason). (I've obscured the actual address in the example above, but kept the same format).

Having sent the email, I've certainly not gained instant access to Ask again - I rather think that it will be quicker to get a new IP address from the ISP's DHCP server than to sort out Ask's broken blacklist. If Ask wants to use a blacklist system then they should probably expire IP addresses off the blacklist say a few hours after whatever behaviour it is that triggers the inclusion on the list was last detected. That way, zombie machines that continue to do something bad via Ask will remain blacklisted and hence blocked, but legitimate users who inherit an IP address that was previously used by a zombie are not permanently banned.

Labels: ,

Sunday, January 14, 2007


Findory rides into the sunset

Searching is for when you know roughly what you are looking for.

An alternative way of finding information is for it to be recommended to you. One of the leaders in recommendation systems is Amazon.

Findory tries to apply some of the ideas Greg Linden learnt when building Amazon's recommendation systems (and what he's learnt since!), but unfortunately Greg has found it difficult to continue to grow Findory - and has just announced that "Findory rides into the sunset". Roughly speaking, this means that development of the site has slowed to a crawl, and that Greg is to concentrate on other things - which for the moment he explains means health and family.

I'm sorry to hear this - Greg's was one of the best blogs in the search area, backed by his ongoing research interests and development of Findory, and whilst I'm sure his interest in personalizing information will continue, without the need to attend to it on a daily basis, I suspect we will be hearing less from Greg in the future. I wish him well, and sorry he couldn't find a way to continue expanding Findory.

Labels: ,