A Way to Preload Images without JavaScript that is SO Much Better

Responding to my first attempt at preloading images without JavaScript, CSS-Guru David Bowman graces his audience with a most enlightening set of comments. Apparently, the image-preloading technique explained in the article is “major overkill” and “totally ridiculous.” Of course, I will be the first to admit that I am no expert in CSS, but I do enjoy sharing my discoveries and watching as people improve upon them. My first attempt at preloading images without JavaScript may indeed be “pretty crappy,” […] Continue reading »

How to Cache Mint JavaScript

Recently, I spent some time addressing a few of the performance issues pointed out by Yahoo!’s very useful YSlow extension for Firebug. Working on performance tip #3, Add an Expires or a Cache-Control Header, I encountered some difficulty while trying to get the JavaScript used by Mint to cache as desired. Apparently, the HTAccess directives used to cache my other scripts do not effect the two PHP-generated JavaScript files used by Mint. Although I am not entirely certain, I suspect […] Continue reading »

Unexplained Crawl Behavior Involving Tagged Query Strings

I need your help! I am losing my mind trying to solve another baffling mystery. For the past three or four months, I have been recording many 404 Errors generated from msnbot, Yahoo-Slurp, and other spider crawls. These errors result from invalid requests for URLs containing query strings such as the following: https://example.com/press/page/2/?tag=spam https://example.com/press/page/3/?tag=code https://example.com/press/page/2/?tag=email https://example.com/press/page/2/?tag=xhtml https://example.com/press/page/4/?tag=notes https://example.com/press/page/2/?tag=flash https://example.com/press/page/2/?tag=links https://example.com/press/page/3/?tag=theme https://example.com/press/page/2/?tag=press Note: For these example URLs, I replaced my domain, perishablepress.com with the generic example.com. Turns out that listing the plain-text […] Continue reading »

Taking Advantage of the X-Robots Tag

Controlling the spidering, indexing and caching of your (X)HTML-based web pages is possible with meta robots directives such as these: <meta name="googlebot" content="index,archive,follow,noodp"/> <meta name="robots" content="all,index,follow"/> <meta name="msnbot" content="all,index,follow"/> I use these directives here at Perishable Press and they continue to serve me well for controlling how the “big bots”1 crawl and represent my (X)HTML-based content in search results. For other, non-(X)HTML types of content, however, using meta robots directives to control indexing and caching is not an option. An […] Continue reading »

Series Summary: Building the 3G Blacklist

In the now-complete series, Building the 3G Blacklist, I share insights and discoveries concerning website security and protection against malicious attacks. Each article in the series focuses on unique blacklist strategies designed to protect sites transparently, effectively, and efficiently. The five articles culminate in the release of the next generation 3G Blacklist. Here is a quick summary of the entire Building the 3G Blacklist series: Continue reading »

Perishable Press HTAccess Spring Cleaning, Part 1

While developing the 3G Blacklist, I completely renovated the Perishable Press site-root and blog-root HTAccess files. Since the makeover, I have enjoyed better performance, fewer errors, and cleaner code. In this article, I share some of the changes made to the root HTAccess file and provide a brief explanation as to their intended purpose and potential benefit. In sharing this information, I hope to inspire others to improve their own HTAccess and/or configuration files. In the next article, I will […] Continue reading »

Perishable Press 3G Blacklist

After much research and discussion, I have developed a concise, lightweight security strategy for Apache-powered websites. Prior to the development of this strategy, I relied on several extensive blacklists to protect my sites against malicious user agents and IP addresses. Over time, these mega-lists became unmanageable and ineffective. As increasing numbers of attacks hit my server, I began developing new techniques for defending against external threats. This work soon culminated in the release of a “next-generation” blacklist that works by […] Continue reading »

Building the 3G Blacklist, Part 5: Improving Site Security by Selectively Blocking Individual IPs

In this continuing five-article series, I share insights and discoveries concerning website security and protecting against malicious attacks. Wrapping up the series with this article, I provide the final key to our comprehensive blacklist strategy: selectively blocking individual IPs. Previous articles also focus on key blacklist strategies designed to protect your site transparently, effectively, and efficiently. In the next article, these five articles will culminate in the release of the next generation 3G Blacklist. Continue reading »

Building the 3G Blacklist, Part 4: Improving RedirectMatch in the Original 2G Blacklist

In this continuing five-article series, I share insights and discoveries concerning website security and protecting against malicious attacks. In this fourth article, I build upon previous ideas and techniques by improving the directives contained in the original 2G Blacklist. Subsequent articles will focus on key blacklist strategies designed to protect your site transparently, effectively, and efficiently. At the conclusion of the series, the five articles will culminate in the release of the next generation 3G Blacklist. Continue reading »

Building the 3G Blacklist, Part 3: Improving Security by Blocking Rogue User Agents

In this continuing five-article series, I share insights and discoveries concerning website security and protecting against malicious attacks. In this third article, I discuss targeted, user-agent blacklisting and present an alternate approach to preventing site access for the most prevalent and malicious user agents. Subsequent articles will focus on key blacklist strategies designed to protect your site transparently, effectively, and efficiently. At the conclusion of the series, the five articles will culminate in the release of the next generation 3G […] Continue reading »

Building the 3G Blacklist, Part 2: Improving Security by Preventing Query-String Exploits

In this continuing five-article series, I share insights and discoveries concerning website security and protecting against malicious attacks. In this second article, I present an incredibly powerful method for eliminating malicious query string exploits. Subsequent articles will focus on key blacklist strategies designed to protect your site transparently, effectively, and efficiently. At the conclusion of the series, the five articles will culminate in the release of the next generation 3G Blacklist. Improving Security by Preventing Query String Exploits A vast […] Continue reading »

Building the 3G Blacklist, Part 1: Improving Security by Exploiting Server Attack Patterns

In this series of five articles, I share insights and discoveries concerning website security and protecting against malicious attacks. In this first article of the series, I examine the process of identifying attack trends and using them to immunize against future attacks. Subsequent articles will focus on key blacklist strategies designed to protect your site transparently, effectively, and efficiently. At the conclusion of the series, the five articles will culminate in the release of the next generation 3G Blacklist. Improving […] Continue reading »

Pure CSS: Better Image Preloading without JavaScript

After reading my previous article on preloading images without JavaScript1, Nanda pointed out that adding extra markup to preload images is not the best approach, especially where Web Standards are concerned. Mobile devices, for example, may experience problems when dealing with the following preloading technique: /* ADD THIS TO CSS */ div#preloaded-images { position: absolute; overflow: hidden; left: -9999px; top: -9999px; height: 1px; width: 1px; } <!– ADD THIS TO XHTML –> <div id="preloaded-images"> <img src="https://perishablepress.com/image-01.png" width="1" height="1" alt="Image 01" […] Continue reading »

XHMTL/CSS Remix: Creative Commons License

[ Screenshot: Creative Commons Deed - Remixed ]

Not too long ago, I played with the idea of releasing article content under a Creative Commons (Attribution-NonCommercial-ShareAlike 2.0) License. At the time, I wanted to host my own copies of the two associated CC license pages. During the process of uploading the pages to my own server, several minor adjustments (regarding image paths, etc.) needed to be made to the source code. After tweaking a few things in the XHTML code, I began snooping around in the pages’ CSS […] Continue reading »

2G Blacklist: Closing the Door on Malicious Attacks

Since posting the Ultimate htaccess Blacklist and then the Ultimate htaccess Blacklist 2, I find myself dealing with a new breed of malicious attacks. It is no longer useful to simply block nefarious user agents because they are frequently faked. Likewise, blocking individual IP addresses is generally a waste of time because the attacks are coming from a decentralized network of zombie machines. Watching my error and access logs very closely, I have observed the following trends in current attacks: Continue reading »

Over 150 of the Worst Spammers, Scrapers and Crackers from 2007

Over the course of each year, I blacklist a considerable number of individual IP addresses. Every day, Perishable Press is hit with countless numbers of spammers, scrapers, crackers and all sorts of other hapless turds. Weekly examinations of my site’s error logs enable me to filter through the chaff and cherry-pick only the most heinous, nefarious attackers for blacklisting. Minor offenses are generally dismissed, but the evil bastards that insist on wasting resources running redundant automated scripts are immediately investigated […] Continue reading »

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