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Networking:
My experience with computer networking started several years ago with two computers sharing a dial up connection, connected together with a piece of crossover cable. A crossover cable is a network cable that crosses the send and receive lines over at one end. It is needed for connecting directly between two network cards. It also needed to be used when connecting between two network hubs/switches. This however is not really the case now as most devices like this now have "auto-sensing" ports which will automatically detect and crossover the send and receive pins if required.
At this time I was also using Windows network setup wizard in Windows XP to get the network working as I had little or no knowledge about networking.
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Shortly after this time, ADSL broadband came to the area in which I live. This was before the introduction of MaxDSL (Up to 8Mb service). I have a friend who lives almost a mile from me across a valley. Unfortunately for him he was just outside the range of the new ADSL service. I, however was not. We had heard about some sort of system that could connect computers over a long distance using special antennas. I done some research on the internet and found the solution which is just two wireless access points and high gain directional antennas mounted outside. I also found that Dlink products appeared to be the most commonly talked about for this purpose. I sourced the equipment and about £400 later I had the following products:
Dlink DWL 900AP Access point (x2)
Dlink ANT24-1400 High gain directional antenna (x2)
Dlink CB09N 9 metre antenna extension cable (x2)
There was a bit of other work to do at my end before the system could be put into operation. At the time I was using a USB ADSL modem. Because of this I decided a server was needed to run 24 hours so the connection would always be available. I cannot remember why I did not change to a router at this stage. This server also provided and area for storing all of the media on the network and an always available printer for the network. Using a bit of old flooring I created a space in my attic for the server to live and installed all the required cables, both mains electric and Cat 5e UTP network cables. This was my first experience at terminating my own network cables.
When it came to setting up the wireless bridge it did take a few days of trial and error to get all of the settings correct on the access points. I also made sure to include as much security as possible. This includes both wireless encryption and MAC address filtering so each access point will only talk to the other. Although the wireless bridge mode will do this anyway I did not take any chances. Once the network was up and running we tested the speed with the Racoonworks speed test and found that we got about 8 Mb throughputs which we were very happy with.
As time went on I made many changes to the network and the hardware at my end. One of the first things I did was to move the network switch downstairs so I could see what was going on. After buying a wireless laptop I then added another access point at my end. I attached both the access point and the network switch to the wall and it became the start of what I now have on my "comms wall" as pictured.
I later became interested in the Apache web server and installed it on the server I already had running in the attic. As I have a static IP with my service provider I was able to very easily make the server public. This however caused problems as to do this I had to switch off Windows firewall despite only needing to allow access to port 80 on the server.
It was now time to replace the USB modem with a router as I should have at the start. The router took its place on the wall with the switch and the access point.
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(Click on images for a larger version)
My newly created server room.
Screenshot from the Dlink DWL 900AP setup.
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Dlink ANT24-1400 at the top of the pole on my house.
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The Dlink ANT24-1400 on my friends house.
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I then started to learn about using port forwarding on the router to access various services on my network from the internet. At this stage I was already using VNC to control my server from downstairs. This was just one of the services I was then able to access from the internet. All the services I can currently access on various ports are:
Web server (Linux Server (serving this page to you))
Web server (Windows Server)
FTP (Linux Server)
FTP (Windows Server)
VNC (Linux Server)
VNC (Windows Server)
SSH (Linux Server)
Webmin control panel (Linux Server)
My Printer (Windows Server using IIS)
My IP Cameras
All of the hardware including the router and access points.
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| Above: My "Comms Wall" as it looks today including access point, ADSL router, 8 port gigabit switch, Homeplug 4 port switch, individual mains isolation switches, power meter, consumer unit, supply/return from the 3Kva UPS in the attic which powers everything on the network and most recently, some dado trunking. |
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Above: The first step in what was to become my "Comms Wall".
Right: My "Comms Wall" after the addition of my first router.
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When I got to the stage talked about above I realized I had a problem. Although I was able to control my Windows server from anywhere on the internet it would sometimes freeze (unusual for Microsoft Windows LoL). When this happened I would have to climb the ladder to the attic to power cycle the server. To solve this problem I replanned the comms wall to include isolation switches for everything. I bought a piece of MDF to mount everything on and went about doing a bit of mains wiring. I since added a consumer unit to this as pictured.
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My servers and 3Kva UPS.
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The access points in my friends house.
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Inside my APC 3Kva Smart UPS. |
My network as it exists today. My house is "Location A" and my friends house is "Location B". Please click for a larger clear image.
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I also started to play a little with Linux and realized the potential for this as a webserver operating system. With a lot of trial and error "Sideburns" was born which was given a home in the attic beside "Atticserver". I immediately fell in love with Linux and could not believe how incredibly stable and reliable it is. My distribution of choice was Red Hat Fedora although I cannot remember why. I have recently changed this server from Fedora to CentOS. I now plan to eventually switch all of my computers to Linux as it is in my opinion far superior to Windows. The introduction of Windows Vista with all of its patronizing security features and its ridiculous appetite for hardware resources has strengthened my opinion.
I of course use Apache 2, SSH, VNC and Webmin control panel among other packages on Sideburns.
Once I decided to run a webserver I wanted to build as much redundancy into the network as possible. The first thing was to use RAID 1 mirrored drives on the server which I was able to do at the Linux installation stage. As I also run a webserver on my Windows server this by default also gave my some redundancy. I build all sites directly onto my Windows server for testing. This means that if my Linux server is down for any reason I can easily toggle the port forwarding options on my router to serve this site from Atticserver instead. This page may actually have been served to you by Atticserver and you would not have known the difference.
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As I have absolutely no control over the speed and reliability of the connection the only other redundancy I could build in was to the mains power supply. Here I had problems. I wanted to buy an APC UPS of at least 1500VA second hand with new batteries from eBay. Unfortunately because I live in Ireland the postage would make this very expensive. To try and solve this issue I bought the largest UPS I could get locally which was a Trust 950VA. I then modified it to increase running time by adding a second battery in parallel with the internal one. This did work well for a short time until the transformer in the UPS went on fire during testing. I replaced this with an unmodified one. With the normal load that exists 24 hours a day of about 200 Watts (two servers, router, switch, access point) I got about 8 minutes backup which was not enough. When my main computer and laptop were switched on (load totaling about 400 Watts) I only got a couple of minutes. I kept this in place for a while until I decided I would just have to buy a bigger one. I thought if I was going to have to pay a lot for postage then I may as well buy a larger UPS. I searched eBay and found a used APC 3000va Smart UPS with brand new batteries installed. It was at a very good price because the battery cover is missing from the front as pictured. When it arrived I had a very difficult job getting it up the ladder and across my attic (which is not floored) into position beside my servers. You can see from the picture why these units are so heavy even without the batteries installed. I now get over two hours backup with my servers which I am more than happy with. I also have Powerchute installed to monitor the UPS and shut down the servers before the batteries fail. I have a power meter connected as pictured both to make sure I am within the limits of the UPS and to measure the impact on the electricity bill. Although this is considerable I was able to justify it by changing every single light bulb both inside and outside my house to energy savers.
Work to my network is ongoing as it is something that I enjoy doing. One of the most recent additions to the network was a Swan Max IP camera which I can of course view from anywhere on the internet. It also records to my Windows server when movement is detected.
I have also recently added Homeplug network switches as pictured to improve the connection to my computer "Other". This computer was originally wireless but the connection was unreliable due to the distance from the access point. When I was connecting the Homeplug switches I had to bypass the UPS as pictured as they would not have worked otherwise.
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