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• Top Ten Mistakes that Hurt Your Google Ranking

  We do a lot of work on our sites to ensure that our readers can find our content through search engines, particularly Google. Over the 10 years we've been publishing media Web sites we've successfully avoided pitfalls that could damage referrals from search engines. We've also made some significant mistakes - from which we've recovered! Consequently we thought we would share the experience we've gained by putting together our definitive top ten list of mistakes that can damage your referrals from Google (we'll let you guess which ones we were guilty of).

  Written by Ben Gerholt • 08 Sept. 06 17:01

• How to restrain a wild Wi-Fi signal

  Say you wanted to protect your Wi-Fi network from surrounding buildings. The most obvious way to do this would be to secure the devices on your network using the wireless security protocol of choice. A very effective, but more extreme, way to do this would be to secure the building itself by making it act as a Faraday cage, shielding the radio frequency waves used by Wi-Fi.

  Written by Geeta Dayal • 25 Aug. 06 11:31

• Linux primer for networkers: Using the sniffer

  A few years back, I used an old 486 running Red Hat Linux and tcpdump to easily diagnose a client's denial-of-service attack, illustrating the benefits of creating a powerful network analysis tool from "scrap" parts. There are plenty of tools to build a similar Windows-based network analyzer, but Linux can run on machines that can't efficiently run Windows.

  Written by Greg Schaffer • 05 May 06 10:55

• 802.11T puts WLANs to the test

  Buyers of Wi-Fi equipment and systems must be assured that all products have the performance and stability to carry mission-critical applications and data. However, testing of Wi-Fi, or 802.11, devices and systems for performance and stability is a challenge for the industry because of the complexity of the 802.11 protocol. That is compounded by the inherent mobility of the wireless devices and the prevalence of radio frequency interference.

  Written by Fanny Mlinarsky • 29 March 06 13:53

• Technology delivers high data rates

  An emerging mobile broadband technology can deliver high-speed data services to workers wherever they are.

  Written by Roger Quayle • 22 March 06 11:09

• Everyday Linux gripes

  As you already know, if I have to sit down in front of a computer, I want it to be running the Gnome desktop on Linux. I've watched it mature from a downright ugly, needlessly complex playground for geeks, to an attractive, simple interface that holds its own against commercial alternatives. And yet, every day I still encounter rough edges that make me think there aren't nearly enough folks out there hacking away at this stuff. I'd like to watch.

  Written by Matthew Newton • 11 Nov. 05 14:52

• Security technology targets the LAN

  Access-control lists, originally designed for routers to deny or admit packets entering a network from a WAN, have drawbacks in controlling a diverse group of users accessing LANs. ACLs have no knowledge of traffic-flow semantics or content, can't adjust access rights for individual users, and suffer scalability and performance limitations.

  Written by Joseph Tardo • 27 Sept. 05 09:42

• Biometric authentication

  In this computer-driven era, identity theft and the loss or disclosure of data and related intellectual property are growing problems. We each have multiple accounts and use multiple passwords on an ever-increasing number of computers and Web sites. Maintaining and managing access while protecting both the user's identity and the computer's data and systems has become increasingly difficult. Central to all security is the concept of authentication -- verifying that the user is who he claims to be.

  Written by Russell Kay • 05 April 05 13:28

• Windows dressing

  The Windows graphical user interface (GUI) isn't quite as customisable as the open source desktops are. Microsoft makes Windows dressing less than straightforward by using a plethora of binary files, Registry entries and INI configuration files to determine the look and functionality of the XP GUI. But don't let that stop you: there are many ways to swap out that drab Redmond-designed interface for something more to your liking.

  Written by Juha Saarinen • 28 Oct. 04 08:01

• Explainer: Proposed standard simplifies VPLS

  Virtual Private LAN Service is an emerging technology that lets corporations and carriers segment voice, video and data traffic across a Multi-protocol Label Switching-based backbone network. For corporations, VPLS allows for multi-point VPNs that provide QoS for any traffic type. And carriers can use VPLS to build private IP segments for a corporation across a common MPLS backbone.

  Written by Oded Bergman • 15 Sept. 04 14:22

• Coping with a DoS attack

  We keep hearing about Denial of Service attacks, and how they can bring large organisations to a standstill, yet do we really understand the full range of events that the term encompasses? What does make up a DoS (or distributed DoS) attack, how it is done, and what can you do to prevent it happening to you?

  Written by Louise McKeag • 07 Sept. 04 14:33

• Using TCP Wrappers to restrict connections

  TCP Wrappers (formerly LOG_TCP) is one of the many security utilities written by Wietse Venema. It works by logging the client host name of incoming telnet, ftp, rsh, rlogin, finger etc. requests. The security options you can configure are: access control per host, domain and/or service, detection of host name spoofing or host address spoofing, and setting booby traps to implement an early-warning system.

  Written by Louise McKeag • 22 June 04 09:57

• Securing dynamic web pages

  This article highlights some of the specific security issues around the use of dynamic code environments, such as SSI, ASP and PHP, and what you can do to minimise the risks.

  Written by Louise McKeag • 25 May 04 12:05

• Security considerations when migrating from Unix to Linux

  The Linux server market is expected to grow by 35% from last year, according to research firm IDC. Many of these Linux systems are replacing Unix in corporations looking to reduce IT costs. However, at the same time, there are more attacks on Linux than ever before. So, if you're considering a migration from your Unix systems to Linux, it's important to keep security in mind.

  Written by Suzanne Dickson • 14 Nov. 03 09:19

• Object storage ensures high scalability

  Fueled by the computational power of Linux clusters, data-intensive applications are pushing the limits of traditional storage architectures. Whether mapping the human genome, imaging the earth's substructure to find new energy reserves, or generating the latest blockbuster animated feature, these applications require extraordinary throughput.

  Written by Garth Gibson • 29 Oct. 03 09:11

• How to interpret SAN worldwide names

  All devices on a storage area network need to be uniquely identifiable. This is to ensure that data transmission occurs between the correct source and target device across a SAN fabric or loop.

  Written by Chris Evans • 15 Oct. 03 09:38

• How to quickly Web-enable corporate apps

  With today's focus on efficiency, the ability for workers to access corporate data anytime, from anywhere is on the way to becoming a business best practice. When IT is tasked with implementing a remote access project, a number of stumbling blocks immediately present themselves. One of the largest problems IT must solve is how to provide secure remote access to any and all "legacy" applications (which I define as "anything in production!"), including mainframe and client/server, without requiring a complete rewrite of the applications to make them Web friendly.

  Written by Mark Ehr • 09 Oct. 03 10:40

• Pitfalls of J2ME development

  J2ME does a splendid job of promoting application portability across a diverse set of embedded devices. But some J2ME specs are vague enough that each vendor's J2ME implementation might handle key sections of code in different ways. What follows is a rogue's gallery of maddening variations that can stymie application portability.

  Written by Tom Thompson • 04 Sept. 03 10:00

• How many firewalls do I need?

  A reader writes: "All the news about the worm currently making the rounds got me thinking about adding a secondfirewall internally to protect really critical servers. I'm not sure the benefit would offset the cost. Is this something I should implement?"

  Written by Ron Nutter • 26 Aug. 03 09:24

• 10G matures

  From the inception of its conceptual framework in late 1999 to the standardization of IEEE 802.3ae in mid 2001, 10G Ethernet has been one of the most anticipated and exciting technologies on the internetworking scene. Besides boasting throughput 10 times that of the already-blazing Gigabit Ethernet, 10G finally gives Ethernet-based networks the ability to contend with the more-established WAN technologies such as packet over SONET and ATM over high-speed OC/synchronous transfer mode circuits.

  Written by Zach Fierstadt • 08 Aug. 03 07:44