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WLAN a családi házban
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The user who has Internet connection in single-family house, usually would like to have possibility of using the Internet in various parts of his home or even in the whole domestic premises, i.e. garage and garden. To reach that goal, the perfect solution is a wireless network (WLAN) in 802.11b/g standard.
In the case of difficulty with building cable installation in home, the wireless network can also solve the problem with connection of greater number of household computers to the global network. Depending on the way of providing the Internet to the house, as well as its internal distribution, we distinguish different variants of installations.
Variant I - Internet provided by cable television operator via cable modem with Ethernet output, or local service provider (ISP) using Ethernet cable.
In these cases we need a router with WAN input in the form of RJ-45 Ethernet port. It could be e.g. the routers:
  • TP-Link TL-WR542G N2950 (eXtended Range technology - up to 9 times longer range)
  • WA2204A N2657
  • Linksys WRT54GL N2652
  • Planex BLW-54PM N2645
These devices allow connecting 4 computers using cable and up to a dozen of computers using wireless connection.
Cable from the provider is connected to WAN port (Internet); we connect computers which should have wire connection to adequate ports of the switch. The rest of computers have to be equipped with wireless cards to make possible for them to be connected with the access point built into the device.
Access Point: Linksys WRT54GL (4p-switch &router, 2.4 GHz, 54Mbps)
The Internet provided with the use of Ethernet
Variant II - Internet provided using ADSL technology (e.g. Neostrada tp and Net24 Netia in Poland, or most telecommunications operators worldwide).
We should use the devices:
  • Asmax 704g N2602.
or ADSL modem integrated with switch:
  • TP-Link TD-8840 N2905
  • TP-Link TD-8840B N2906 (Annex B)
  • TP-Link TD-8841 N2908
It integrates ADSL modem, router, switch and access point.
Computers are connected analogically as in the above variant, i.e. with Ethernet cable to the switch and wirelessly to the access point.
Wireless ADSL2+ Router (Annex A): TP-Link TD-W8910G <br />(4p switch, eXtended Range AP)
The Internet provided using ADSL technology
Variant III - Internet provided wirelessly with the use of the set: directional antenna + wireless card in the computer.
At least two devices have to be used. Firstly, we have to connect access point working in AP Client mode to a directional antenna.
  • Planex GW-AP54SP N2626,
  • OvisLink WL-5460AP N2636,
  • AWAP-608 N2646
To operate at 5GHz we should use:
Then the Ethernet output need to be connected to a wireless router like:
  • TP-Link TL-WR542G N2950,
  • WA2204A N2657,
  • Linksys WRT54GL N2652,
  • Planex BLW-54PM N2645.
As the final result we will get the situation similar to the first example.
Access Point: WA2204C (AP/APC 54Mbps)Access Point: Linksys WRT54GL (4p-switch &router, 2.4 GHz, 54Mbps)
The Internet provided wirelessly
Variant IV - Internet provided wirelessly. Some Access Points have been fitted with a very useful function named Wireless Routing Client, which enables us to configure wireless port as WAN port that is normally found in router. It means that the wireless connection can be shared with built-in router by available LAN ports. The advantage of such configuration is compactness - one piece of equipment that performs the role of two devices. The solution allows for creating our own configurable subnetwork that can be properly secured from unauthorized access.
Devices with Wireless Routing Client function:
Due to dual-band radio transceiver, Compex WP54AG N2520 can be used as Wireless Routing Client in both frequency bands: 2.4 and 5 GHz.
Access Point: Compex WP54AG (802.11a/b/g; 2.4 &5 GHz DUAL BAND; 2x LAN - PoE)- CLEARANCE SALE!
AP Compex WPE54AG in Wireless Routing Client mode
What is the router needed for?
Internet service providers usually assign only one IP address to a user. If the user wants to connect a greater number of computers, he may either ask the provider for additional addresses (it usually means additional costs), or use a router with address translation feature - NAT.
As the provider not always has the ability or will of assigning additional addresses, the use of a router is frequently indispensable. Basic configuration of the router consists in WAN address setting - received from the Internet provider, the change of default coding keys, and MAC address setting for WAN port (WAN MAC Clone option), when it is needed, defining local address - the address of gate for the rest of home network computers. It is also required to configure access point: to choose adequate channel, to set SSID, encryption of transmission (the best in WPA standard) and to assign passwords. Each of models offers different additional functions, which can be employed as the user is familiarizing with the device.
Where to place the access point?
The place an access point is situated strongly influences the range of home network within a house and its surroundings. An overall rule of radio network functioning in rooms says that a signal has usually useful level after it passes through 3 walls or 2 ceilings.
So, it may be optimal to place access point in the location where the wireless network is mostly used in home (i.e. drawing room, study or ... bedroom). If it has to be used in the whole house, it is better to place it in the geometrical center of the house. However, if we want also to cover garden with the signal, the device should be placed nearby window. In that situation, there is a possibility that in more distant rooms the signal will be low. Generally, it is impossible to estimate the range and level of the signal in concrete instance, without tests. Tests are the most authoritative way of finding optimal solution and give reliable answers instantly.
If we do wish to cover the whole house and garden, but the location of the access point nearby a window doesn't bring appropriate effect, we can try to do some trick with two antennas.
Why do some devices have two antennas?
Some part of wireless devices is equipped with two stub antennas; the other has only one antenna. The device equipped with two antennas uses them in specific way to improve quality of transmission. It is so called collective reception (diversity).
It consists in checking by the receiver which antenna provides stronger signal, and only that signal passes for further processing. The same antenna is then chosen to send the data. Advantages coming from the use of that mode will be perceptible mainly indoors - in rooms - where radio waves are being reflected many times by walls, appliances, and people. When receiver has only one antenna, it may happen that radio wave coming to it will be overlaid on the other wave which was reflected and came to the receiver with some delay, traveling longer way. This situation may cause signal fades and drop of bandwidth. When the device has two antennas, if the signal fades out in one antenna, there is a chance that the other antenna will receive it much better and the transmission will be retained.
It should be remarked here again that the access point checks every time which antenna receives stronger signal, and this antenna is used, so it is impossible to simultaneously utilize them as two independent antennas. However, the property described above, allows us to improve home network operation. Reverting to the example, when we want to cover whole house and garden with the signal we may place access point in the central point of the hose. We connect original stub antenna to one antenna output which will serve the home needs, and then we connect a panel antenna (e.g. the antenna ATK-P1 - A7130), using special cable, to the second antenna output.
We direct the antenna to the outside of the house or install it nearby the window facing the garden. With this configuration, we have possibility of using wireless network at home or in the garden. According to what has been written above, it won't be possible to serve two wireless clients simultaneously - one at home and the other in the garden, because the access point has to choose whether to use stub antenna or panel antenna. This kind of operation would be very unstable. Anyway, a few wireless clients inside the house can work simultaneously, because all of them are served by the same antenna. Similarly, there shouldn't be any problem with serving a group of wireless clients in the garden.
How to configure wireless cards?
Configuration of wireless cards isn't difficult task. Following the instructions from the manual we will install the right drivers. Then it is needed to setup correct IP address, gateway (of our router), infrastructure mode, SSID of access point, coding keys. Choosing the cards, we should pay attention to the encryption methods - whether they are the same as those of the access point. There are available cards with the older WEP, or with WEP and more advanced WPA encryption. If the cards and the access point support WPA it is recommended to use that kind of encryption.
And what about ad-hoc mode?
Wireless cards can also work in mode ensuring direct connection between them, without any use of access point. If you use Internet on single desktop computer, and occasionally you would like to have possibility of connection to network using laptop with wireless card, the cheapest solution for you will be installation of wireless card in the computer, configuration of it to ad-hoc mode, assigning adequate SSID, coding keys, right IP address (from other class then IP assigned by internet provider). Then you configure wireless card in laptop in the same way, and you run, on the desktop computer, "internet connection sharing" or any application working as software router. This way you build simple wireless network at little cost. Disadvantage of the solution is only the fact that the desktop PC must be turned on when you need internet connection on your laptop.
Wireless ADSL2+ Router (Annex A): TP-Link TD-W8910G <br />(4p switch, eXtended Range AP)
Example of application
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