Monday 25 August 2008

Search engine rankings

I was helping out an organization recently that wanted to improve its rankings in Google searches, so I thought I’d pass on what I told them. Now I’m sure to many of you this is old news, but there must be lots of other people who could benefit from the information.

Whether a site appears on the first page of a search depends on its ranking. On the Technology Web page, Google tells us that: “PageRank reflects our view of the importance of web pages by considering more than 500 million variables and 2 billion terms”.

First of all, how do search engines know what pages you have on your Web site? The answer is they use spiders or bots, which are automated computer programs that access Web pages and record the links they find. These links are then added to a list of sites to be crawled by the bots in the future. Google’s programs are called Googlebots!

But perhaps more importantly, how does Google (or any other search engine) know about your Web site in the first place? The answer to that is that it either found a link on a site that it crawled earlier, or the Webmaster submitted the site to Google to be added to the list. For Google the URL you need is
www.google.com/addurl. For Yahoo, it’s search.yahoo.com/info/submit.html. And for MSN, it’s search.msn.com/docs/submit.aspx.

Once a Googlebot has crawled your site, the Web pages are downloaded and analysed. The words and phrases that they contain are stored in the index. The index will also note the title, which it uses when displaying a short preview on the search page. The indexing process is fairly sophisticated and gets information from the HTML, images, and even Flash files.

Obviously, each search engine uses a different algorithm to calculate the ranking of a page, but there are techniques that can help increase a Web page’s ranking. One quite important one is the number of other Web pages that link to that page. The more inbound links that exist, the higher the ranking. The problem with that is links to your site are outside your control to a large extent.

The best technique is the use of tags in the head section of a page. Step one is to give a page a meaningful name (meaningful in terms of the Web page’s contents. “New page” is useless. The next step is to get the meta tags right. For example:
meta name="description" content="This page ..."
And include words that then re-appear on the page. It’s also a good idea to include as many words as possible. Google doesn’t use the keyword meta tag.

When it comes to laying out the contents of a Web page. It is usually recommended that h1 and h2 tags, or bold text are used to make sub-headings obvious to the search engines.

Google also likes to use the ALT tag on images to help build up a picture of a Web page, so include it. It can also help if you are using graphics to navigate (ie an image of a button). If that is the case (you are using graphics for buttons), then it’s recommended that alternative navigation is also provided. This usually means hyperlinked text at the bottom of the page.

A site map can help search engines know which pages of your site can be searched and to find data.
http://www.xml-sitemaps.com/ will help you build an XML site map that can be submitted to Google, or a text site map for submission to Yahoo. A sitemap also creates more site links – which increases the ranking.

And what should you avoid? Don’t use frames – which means throwing away that old copy of Frontpage you thought you could use to build your Web site. Also, don’t build the site using Flash because not all search engines can derive any information from Flash files. Also avoid writing about a topic on a page that’s different from the title and meta tags.

And finally, update the content regularly so it looks fresh and interesting, and people will want to revisit.

Any comments?

Monday 18 August 2008

Joining the penguins

There comes a time, when tucked away in odd corners, you find old computers. These computers have been replaced because they did not have USB ports, or they ran old versions of Windows and had small hard drives and it was just easier to buy a new one rather than keep upgrading. Or they were just so slow that a day’s work seemed to take about three days to complete. Or they were worryingly insecure. Or… the reasons why they were replaced just go on. But there is a way to get some more life out of that old hardware, a way to increase their Return On Investment (ROI), a way to make them useful once more – and that’s to install Linux.

Why choose Linux? Well the first answer is that it seems to run on any old hardware – you don’t need 2GB of RAM for the operating system etc. Secondly, it’s free. So if you don’t like it, it’s cost you nothing (well maybe the price of a blank CD!). Thirdly, Linux upgrades incrementally, rather than major leaps such as ME to XP and XP to Vista. This makes upgrading fairly easy, and takes away the nightmare of running an unsupported operating system.

The thing that puts off many people from using Linux is the choice. Now I know that Vista comes in lots of versions (Home Basic, Home Premium, Business, Ultimate), but Linux comes with varieties such as Red Hat, SUSE, Ubuntu, Kubuntu, Debian, Gentoo, Puppy, Mint, etc, etc. Which one is best? And an answer of, “it all depends”, just makes it too complicated. However, I have been using versions that fit easily onto a single CD and allow you to boot up from the CD, even if Windows is installed on the hard drive.

So let’s say you have made a choice of which Linux variant you want (Puppy or Mint might be good starting points – but so are the others). The next stage is to download the Linux distribution you want (a distro). The download files are usually ISO files, and these need to be burned onto CDs as ISO files. With Nero, for example, tell it to burn an image from the File menu and then Open the ISO file.

The next stage is to check that the computer will boot from CD. Go to the BIOS and, if necessary, change the boot priority to the optical drive. Usually the computer will boot OK from your new boot CD. Just watch out for any messages about booting from CD – it’s definitely what you want to do.

The clever thing about the small Linux systems is that they will discover hardware. From then on you can access files on the old C: drive. It should also discover old hardware and make it available. It will then discover networking capabilities and allow you to get on to the Internet.

I would just play with this version of Linux for a while and see how it goes. Once you are happy that Linux gives your old hardware a new lease of life, then install it – so it will boot from the hard drive in future.

There are loads of Web sites that explain the nitty gritty of installing the Linux variant of your choice. They explain things like the /home directory, /root, /boot, /dev/sda or /dev/hda, and /swap.

Like it says in the title, I have started to use Linux for more things than just recovering data from “dead” Windows laptops. Give it a go – and then try OpenOffice as an alternative to Microsoft Office and Firefox as an alternative to Explorer, if you’re not doing so already.

Monday 11 August 2008

25 years of DB2

What kind of a mainframe blog doesn’t mention DB2’s 25th birthday? I hang my head in shame. DB2 celebrated its birthday on the 7th July this year, and like a forgetful relative, I don’t send a card until a month later. But, finally, here is my take on 25 years of DB2.

DB2 – which stands for DataBase 2 – first saw the light of day as an MVS application in 1983. It is a relational database and uses SQL (Structured Query Language) – pronounced SQL by mainframers and "sequel" by non-mainframers, apparently. Where did it come from? In the 1970s, Ted Codd created a series of rules for relational databases, which DB2 was very loosely based on. However, originally, DB2 did break many of Codd’s rules. There was also a VM product called SQL/DS, which was similar in nature.

As well as MVS (or z/OS as it’s called in its current incarnation), DB2 is available on other platforms. During the 1990s versions were produced for OS/2 (if you remember that one) Linux, Unix, and Windows. There have been a variety of naming conventions over the years. Things like DB2/VSE and DB2/6000, which were replaced by DB2 for VSE and then DB2 UDB (Universal DataBase). This current naming convention can make it harder to work out whether a mainframe version of DB2 or a server version of DB2 is being discussed in any article on the topic.

Interestingly, although mainframe and server versions of DB2 are currently very similar in functionality, they are written in different languages. The mainframe version is written in PL/S and the server version in C++.

In the early days, the big competition was Oracle and Informix. Well, IBM bought Informix in 2001, and happily runs Oracle on a zLinux partition. There is also a 31-bit version of Oracle available for z/OS.

Of course, DB2 isn’t IBM’s only database. It has its relational IMS DB. People interested in IMS DB will be interested in the Virtual IMS Connections user group at
www.virtualims.com.

As they say, other mainframe databases are available, including: CA-Datacom, CA-IDMS, Cincom’s SUPRA, Computer Corporation of America’s Model 204, Select Business Solutions’ NOMAD, and Software AG’s Adabas.

DB2 is currently at Version 9, which you might remember was code-named Viper before its launch.

Happy belated birthday DB2.

Monday 4 August 2008

Birthday blog

Just to be clear, it’s not my birthday, but I’ve just passed the blog milestone of 104 blogs – so I am now into year 3 of blogging – woo woo!! Blog 1 was published on the 19th July 2006.

In the two years I’ve been writing this blog, I’ve tried to stay focused on mainframes and the accompanying software, but sometimes I’ve included stuff about PCs (we all use them), and occasionally I’ve written about useful gadgets I’ve reviewed.

Perhaps one criterion for measuring how successful a blog is, is by counting the number of people who read the blog. A second method would be to see how often a blog gets mentioned by other (unrelated) bloggers. Here are some of the places that have picked up on this blog over the past year.

"Sometimes small isn’t beautiful" from the 21st July was quoted by Mark Fontecchio in Mainframe Propellor Head (http://itknowledgeexchange.techtarget.com/mainframe-blog/more-on-the-ibm-swallowing-of-psi/). "Saving money on mainframes" from the 9th June 2008 was discussed by both Mark Fontecchio in Server Specs (http://serverspecs.blogs.techtarget.com/2008/05/20/mainframe-specialty-processors-do-they-really-save-money/) and Marc Wambeke in Mainframe Watch Belgium (http://mainframe-watch-belgium.blogspot.com/2008/05/saving-money-with-ziip.html). "IBM launches its zX machine" from the 3rd March 2008 was quoted by Greg Meckbach in the Enterprise Infrastructure eNewsletter (http://www.itworldcanada.com/a/Daily-News/eac638c9-a68d-42f7-8605-be83e7b4d03b.html) and in Computerworld Canada (http://www.computerworldcanada-digital.com/computerworldcanada/20080321/?pg=10). "The Arcati Mainframe Yearbook 2008" blog on the 18 February announcing the arrival of the 2008 edition of the Arcati Mainframe Yearbook (www.arcati.com/newyearbook08) was picked up by Mark Fontecchio in his article in ServerSpecs (http://serverspecs.blogs.techtarget.com/2008/02/20/the-2008-mainframe-yearbook-is-out/). "IBM future – Elseworlds" on the 4th February was heavily quoted from in Mark Fontecchio blog "And starring as the Hulk... IBM" (http://serverspecs.blogs.techtarget.com/2007/12/31/and-starring-as-the-hulkibm/).

It's good to know that people are reading the blog and referring to it in their own blogs and on their Web sites. Looking to the future, in the next year, I plan to continue highlighting trends and interesting new products in the mainframe environment, while occasionally discussing other computing developments that catch my attention.

If anyone reading this blog is looking for a technical writer, please e-mail me at Trevor@itech-ed.com.

And finally, a big thank you to everyone who has read my blog during the past two years.