Services For Website Monitoring

If you have already gone through the hassle of constructing a website and hosting it with a reliable company, you will obviously expect your website to be available 24 hours a day and 7 days a week, as downtime can result in lost sales and customers being frustrated.

Regrettably, many technical problems come into play which are beyond your control and can cause your web site to go down or to become sluggish. Sometimes, server hardware and software can fail and your host might schedule downtime for maintenance chores. A fast recognition of failures can be the best defense for getting things back on track, so many companies will offer website monitoring services that will automatically alert you if your site goes out of order.

Hundreds of companies are available and can provide monitoring services. Some might be free of charge, whereas others will charge you anywhere from $5 to $60 per month. Of course, the paid services usually offer more features and will also allow you to use the same service with many different web sites. Web monitoring is not done in a continuous way – and time intervals tend to range from every 3 minutes to every hour. The paid services generally offer the most comprehensive monitoring.

Monitoring functions by sending an automatic request to your website and then checking for the response. These requests are similar to what a web browser makes and the response to that request will determine whether the site is up or down. Requests are usually sent from many different geographical areas in order to ensure that the site can be accessed from many different parts of the world.

If the response code reads OK (200, 301, 302, 401, 403) then nothing happens and the monitoring software will wait for the next scheduled check. If the response code indicates that the web site cannot be reached, there will be a second check a few seconds later from a different location. An alert will be issued after 3 or more checks.

An alert can be sent to one or numerous email addresses or to a mobile device such as a pager or mobile phone. This will enable you to keep in touch with your hosting company as soon as possible in order to ensure that they are aware of the problem and are working to solve it. Together with HTTP traffic, some website monitors might also check HTTPS, FTP, SMPT and POP3 so that all the functions of your website are seen to.

Apart from alerting you about downtime, these services will also provide some useful statistics in the shape of log files that will indicate how often a site can go down. This third-party information will be used in order to demand better service from your web host or for a refund in the event of severe amounts of downtime.

If you find that your site has had an amount of downtime which you think is unacceptable, you might want to look for another hosting company. The best method for finding a good host is to ask for other website owners advice. If they are satisfied with their own service they will usually be more than happy to direct more business to their existing host.

Michael Beattie is contributing editor at This article may be reproduced provided that its complete content, links and author byline are kept intact and unchanged. No additional links permitted. Hyperlinks and/or URLs must remain both human clickable and search engine spiderable.

From The Server To The Web Browser: What Goes On?

Every time you click on a link in a web page or type a URL into your web browser you are in fact making a ‘request’ for a certain document. That request is carried out with the Hyper Text Transfer Protocol (HTTP) and sent over the Internet all the way to the server which is keeping the document in question. If everything goes well the server responds by sending the document, which is usually a web page of text and graphics.

The HTTP is part of the Internet Protocol(IP) suite. It is used by the ‘client’ which here is the web browser in order to create a connection with the server which hosts a website in particular. The server waits for incoming requests by monitoring TCP port 80.

Transmission Control Protocol (TCP) is used to produce connections between two computers on the Internet so that they can exchange data. TCP has provisions for identifying the requesting computer and also for transmitting information with time stamps so that it can be gathered again in the correct order once it arrives to its destination.

There are many standardized uses for TCP ports. For example, TCP port 21 is usually reserved for FTP (File Transfer Protocol) in order to upload and download files. Port 80 is usually employed for HTTP.

If your server gets a request string on TCP port 80 in the shape of GET / HTTP/1.1 it will send a response code which will depend on whether the requested web page is available or not. A classic request goes like this:

GET /faq.html HTTP/1.1

This will be a request for The ‘Host’ needs to be specified in order to distinguish websites which are hosted on shared servers. If faq.html is available the server will then reply:

HTTP/1.1 200 OK
Date: Mon, 12 October 2005 22:38:34 GMT
Server: Apache/1.3.27 (Unix)(Red-Hat/Linux)
Last-Modified: Wed, 08 Jan 2003 23:11:55 GMT

…followed by the actual web page.

HTTP/1.1 200 OK signifies that the web page you requested is available. Other codes can also be returned. For example, the code 404, signifies that the server cannot find the page you requested. The web page is sent through TCP as a set of data packets with a header each that will specify its destination and order in the data stream. The various packets can all take on various routes in order to reach their target. Each packet is sent through a router which polls other routers which are near by. However, if a connection with the first router is unavailable, the data will be sent through another one.

As the data is received, the client (web browser) will send back an acknowledgement. This will ensure that all the packets are received within the right amount of time. If they aren’t, they will be re-transmitted by the server. TCP will also check that the data is not damaged. The data will be rearranged in the right order thanks to the sequence number of each data packet. And there you go! Then the web page appears on your computer screen.

Also, the TCP connection can be kept alive for further requests from the client. This will enable several pages to be requested within a short span of time without causing the overhead to open and close TCP ports. The client or the server can end the connection any time by just closing it.

J. M. Stevens is contributing editor at This article may be reproduced provided that its complete content, links and author byline are kept intact and unchanged. No additional links permitted. Hyperlinks and/or URLs must remain both human clickable and search engine spiderable.