The Cloud – Does it have a silver lining?

By Laurie

There is a lot of talk about The Cloud and Cloud Computing or sometimes referred to as Nebulous Computing.
So, what’s all the fuss about?

Lets take a look at the story so far.

The First PCs

The first PCs were functional and stand alone. Some required a rather laborious swapping of diskettes to load
up the operating system and further swapping for data storage.

The First Useful PCs

The first useful computers contained a hard disk (drive) and a floppy disk drive (Now often termed removable media and used to
refer to devices that allow you to take data from your PC. CD, DVD, Zip Drives etc.)

The First Really Useful PCs

The first really useful computers contained above with the addition of a Mouse (Pointing device), a colour graphical user
interface (GUI) and most importantly of all, a network connection. This last stage is most important as it allows multiple users on multiple
machines to share information with each other.

Sharing Information

This concept of sharing information has been accessible to scientists and engineers since the 70’s but required a more technical approach.
So, now it is available to the common man. (And royalty alike)

Network Model

Although there have been a number of different ways using the operating systems and the applications, the ability to store data has
always been the primary concern for the user. The type of network model and its hierarchy have been of no interest, nor should it, other than
the ability to chose who can access what.

The different approaches to the network model came about as vendors, users and companies decided the best way to use the new technology.

The client server model was used to give individual users and computers permission to access certain parts of the network. It was also possible to allow or deny
users access to different applications and to count the maximum number of users using an application at a given time. This
was very useful, as in the standalone environment each computer would require a unique licence to be purchased for it. Now companies would only pay for the maximum
number of concurrent users.

With regard to the data, some companies would still have a hard disk in the PC and this would synchronise with the server when they were connected. (Useful for remote
working on a laptop)

The Diskless Workstation

The diskless workstation might seem like a step backwards but it wasn’t. There were certain environments where organisations wanted
to control the data very tightly. For example, where the data is very sensitive or maybe in a college where users are given some storage space
on the server but it is not intended for them to leave their data on the PC.

Operation

Diskless Workstations (PCs) work by having something called a network boot. When the PC is switched on it requests its network connection
and then based upon its identity it is given the Operating System to load. Once loaded the login determines which applications and data the users can
access.

Fault Tolerance

This type of system requires a fast network and zero defect storage. The sort of storage that would be required would be something like RAID 5.
RAID stands for Redundant Array of Inexpensive Disks. RAID 5 will continue to work with a failed disk and notify the network controller who can remove
the faulty disk and replace it without taking the system down. The new disk is rebuilt on the fly.

Back to the Cloud

At the start of this post we were going to look at The Cloud. In reality, the diskless workstation is how the cloud is intended to work but with one
major difference. The diskless workstation was intended to work within an organisation across their network whereas The Cloud is intended to
work across the Internet with the storage outside of the organisation. So, although technically very similar there are a number of issues related to security, connectivity and up time which may impede
the rapid deployment to the cloud. So, lets take a balanced view and look briefly at the Strengths, Weaknesses, Opportunities and Threats (SWOT)
of the use of Cloud Computing.

Strengths

Economy of scale from a data storage wholesaler
Fault tolerance
Mobility
Individuals can have big company service

Weaknesses

Fault tolerance
Connectivity

Opportunities

Reduce data storage costs
Latest implementation of software

Threats

Upgrades at the speed of the provider. (Good or bad it may not suit the end user.)
Data security
Does the host have fault tolerance across multiple sites

Is the Cloud for me?

I can see that at some point in the future I will subscribe to the Cloud but I will not be an early adopter. Most of my work takes place in the same location and
my broadband connection is slow and from time to time intermittent. Once BT have upgraded the area to BT Infinity I will look again.
I do not envisage a subscription to Operating Systems or Applications early on as I prefer to work with current version minus one or two.
Like many people most of my work with the popular applications uses only a fraction of their capability

When I do join the Cloud I will be asking the provider for the geographical locations of their fault tolerant data centres. I will want to know how much
bandwidth they have and how much of that I will get when connected.

categoriaTechnical commentoNo Comments dataJanuary 9th, 2014
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Handling Error Messages

By Laurie

Error Messages

Some of the errors you may have seen include 400 which is caused by bad syntax, 403 which is caused by a forbidden request for a page, or directory access. Lastly, the most common, 404 Not Found. That is, page not found

404 Error

In this Post we are going to look at the 404 error ‘Page Not Found’. Although we will concentrate on the 404 error the same solution can be used to intercept the other numbered error messages.

I am sure we’ve all been browsing from time to time and all of a sudden we get a glimpse of a flash of “404 Error Page not found” before we are taken to our ISP’s preferred error message page which tends to be full of adverts for which they are probably charging. (Nice work if you can get it!)

Think about this missed opportunity to interact with customers and potential customers. Not only can you interact with them but you can also find out about the usability of your site by entering into a dialogue with them and build that all important relationship from something that should not have happened.

It’s My 404 Error

Lets not forget that the error was caused by your website or your visitor. Lets look first at how we can redirect the error message to our own page so we can get our customer back on track. Or continue the dialogue.

What we are going to do is tell our website how we want it to behave when it encounters a numbered error. Instead of going to the default page, or even the ISP’s sales page we want it to come to our page. Or more accurately our error document, as it is called.

Our 404.html Error Page

So, lets return to the 404 error. We are going to produce a file called “error404.html” or “404.html” This is a standard html document where we will enter the following code:

html Start

Welcome to our 404 error page. The fact that you are here means that your attempted page request has failed.

This error means that there was no web page with the name you specified at the web site. This could happen for a variety of reasons:

  1. The document does not exist anymore.
  2. The document may have been renamed.
  3. The document has moved.
  4. The document may have been unavailable at the point of requesting it.
  5. The document url has become corrupt or malformed.

Use the browser back button (Usually at the top left of the page) to return to the previous page and try again. If when you try again, you are returned to this page, then please use the contact form below and let us know what you were trying to do so we can fix it.

html end

The above html code is the message and assistance that we want to provide. Remember to make this relevant to your target audience and if you dont know who they are then keep it very simple.

Upload The 404.html Document

Upload you personalised error document to the relevant domain such as http://www.your_domain.com/404.html This document does not have to be loaded onto the domain from where the error might occur. So, its quite easy to have one really usefull error document for all of your sites.

.htaccess File

Next, create a .htaccess file using NotePad or a similar editor that doesnt put hidden code into the file. So, dont use Word. Add lines which specify the substitution. Here are examples of specifying error documents
which will be called for a given error condition using relative and absolute addressing. (If you are going to use another domain for the 404.html file then you cannot use relative addressing.

ErrorDocument 404 /404.html
ErrorDocument 404 http://www.your_domain.com/404.html

Upload .htaccess File

Upload the .htaccess file into your home directory. You will not see it once uploaded since it gets hidden by the server.

Test It

Go to http://www.your_domain.com/anything_you_want.html

Assuming you replace your_domain.com with the actual domain you’re using and that you dont have a a file called anything_you_want.html, the error page you produced will appear.

PHP Problem

The code above will not work with php files. So, if you use PHP pages then you need to do the following:

Adding the following piece of code to the .htaccess file
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule (.*) /errordocument.html

Create a file named “errordocument.html” containing your error message content. Or rename errordocument.html to 404.html

Home directory here means the directory your domain is pointing to in the Control Panel. It could be root directory (/.) or a directory named mydomain etc.

categoriaTechnical commentoNo Comments dataJanuary 7th, 2014
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Round Corners and Cascading Style Sheet 3 (CSS 3)

By Laurie

CSS 3! I didn’t even know there was a 1 & 2

Well the plot thickens. With traditional software we could expect a release of software but, of course, CSS isn’t software it’s more of a protocol. This is where things get tricky. The CSS 3 standard exisits today but now we must wait for the browsers to become CSS 3 compliant.
Most of us can guess which ones are lagging behind. It also appears that the functionality offered by CSS 3 is being rolled out rather than a browser being completly CSS 3 compliant.

The reason I started looking at CSS 3 in the first place was because I wanted to produce a tabbed menu but I wanted the tabs to be curved. So, I Googled something like CSS curved corners and so began my journey of discovery.

It appears that the most popular browsers are capable of rounding the corners but this is done as a workaround.

For example, the CSS line to acheive the rounded corners at each corner is border-radius:10px;

The following lines need to be added for other browsers:

-moz-border-radius
-webkit-border-radius

or the additon of a file called border-radius.htc

The above list is not by any means complete and there are still workarounds which involve using curved .gif images.

None of the solutions appears to be complete. For example some of the solutions and the .gif image, which is a fixed size, will not scale when the users changes the zoom. This means that anyone producing pages for large organisations will have trouble complying with the Disability Discrimination Act (DDA) for those people who need to see the pages in larger fonts or magnified.

To get solutions to work in some browsers where you use layering requires additon JavaScript to maintain the consistency of the page rendering.

If at this stage you are asking yourself what all the fuss is about then take a look at this site www.members.smartmarketingwarriors.com using Firefox, if you usually use IE, and IE if you usually use Firefox.

That simple act of taking the edge off of the corners, I believe, transfers the site from a very functional technical solution to something more slick and more of the sort of thing you would expect from the marketing solution.

So what now? For me, I am going to put the border-radius:10px lines and some of the other lines which are independant of additonal code to make them work into my new sites and test them in the browsers which currently support the command and/or work. I’ll wait for the other browsers to catch up and when they do the curves will appear.

Of course, using feedback from my Google Analytics account I can see that almost all of my visitors use IE or Firefox. So, thats where I will concentrate my efforts.

categoriaTechnical commentoNo Comments dataJanuary 5th, 2014
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