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Email Blacklists

Posted on June 17th, 2010 by Victoria Pal in Tech

email blacklistSooner or later email blacklists become the nightmare of most system administrators. Long story short - when your email provider is reported as a source of email spam, a lot of your email messages won't reach your family, friends, business partners, loyal and prospective customers alike.

Becoming part of a blacklist isn't what gets other email providers to filter you, it is the way they decide to do so. Blacklisting causes problems when the administrator decides to simply filter out all emails coming from a network device on a blacklist. Medieval doctors did a similar job when taking off an arm to save the patient from an infected finger. Clean email has no chance of reaching its intended location. Decent e-mail service providers usually filter spam, employing methods that utilize multiple filters before deciding whether an email message is spam or not.

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Content Delivery Networks

Posted on June 16th, 2010 by Victoria Pal in Tech

Content Delivery Networks / CDN9Almost all of us enjoy the benefit of a Content Delivery Network, whether we realize it or not. Content Delivery Networks (CDN) also referred as Content Distribution Networks is what you call a system of network hardware containing copies of data located in various geographical locations, depending on the local demand from clients requesting the resources.

Content delivery networks are especially useful for delivering rich media content to users from different geographical locations, avoiding delay and bandwidth overload near the main server. CDNs can contain all types of data, but most often they are used to distribute data which demands high bandwidth. A few rough examples are downloadable software, media files and documentations, multimedia streams, online games as well as database queries, etc.

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DDoS Attack

Posted on June 15th, 2010 by Victoria Pal in Tech

DDoS attackThe end goal of Denial-of-service attack (DoS attack) or distributed denial-of-service attack (DDoS attack) is to make a resource unavailable to its users. The attack can be carried out on different levels, depending on the target and people involved. In essence, the attack represents a highly intense attempt by one person or more to hinder web sites or specialized internet services from running properly, causing financial losses to the owner of that resource.

Depending on the motivation behind the attack, different targets might suffer from it. The attack can be implemented by a single person, carrying out a personal agenda. Such an attack is highly unlikely to cause too much trouble and will only be temporary. A much bigger problem are organized attacks performed by a group of individuals in pursuit of financial gains. Such attacks can be sustained for longer periods of time and might as well ruin companies relying on online presence. Banks, online retailers, government sites, payment gateways and even root nameservers can become easy prey for organized DDoS attacks.

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Server Cache

Posted on June 10th, 2010 by Victoria Pal in Monitoring

Server CacheWeb caching describes the process of storing frequently used objects closer to the user through browser, proxy or server cache. Caching frequently used content has a positive effect in most cases because it reduces server load, bandwidth and latency. It also helps increase the responsiveness for users on the web.

Modern browsers support caching and require most elements of a page only during the first time a user opens that page. Then CSS files, images and other media are stored in a dedicated folder. This leads to faster loading times and better user experience. The whole process happens without any input from the user.

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Energy Efficient and/or Cost Effective

Posted on June 9th, 2010 by Victoria Pal in Tech

Intel released a new microserver last fall. It is quite small and features a 1.86GHz Quad-Core processor and four memory slots. It consumes 45watts when flat-out, however a 30watt dual-core version was due to be released Q1 2010. Intel's goal is to have a to have a micro server running on 25watts when idle.

Intel's microserver

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