To follow up on the "So you're ready to build a wireless LAN in your home?" article I decided to write this article on finding the right equipment for your home wireless network. In the last article we covered basics on wireless terminology, protocols and equipment. Now we will take what we learned there and apply that to what we need to buy to accomplish what we want our WLAN to have the ability to do.

The first thing we need to decide is what our WLAN requirements will be. In this particular scenario we will use a desktop computer currently located in the area where there is already a DSL broadband connection connected directly to the desktop PC. Now, recently we purchased a laptop computer with built in 802.11g Wi-Fi capability and we wish to share our current broadband Internet connection between the two simultaneously. We also want to have the ability to share files between them and for the laptop to have access to a printer attached directly to the desktop computer.

Immediately we can add three requirements to our list:

• We need to have two wired connections such that we don't have to add additional unnecessary equipment because currently our desktop computer is connected to our DSL modem with a wired NIC (Network Interface Card).
• We need to have a wireless connection that supports 802.11g or 802.11b (since 802.11b is backwards compatible) because 802.11g is the standard that our laptop supports.
• We need a way to share the Internet connection between the desktop PC and the laptop.

Ok, so what’s next? Lets take a look at network speed requirements. At what speed do we want our wireless network to perform? We need to determine what type of traffic and how much of it that we will be transferring over our WLAN to make a decision here. In this particular instance we will be sharing large image, video and music files. We will also be sending high graphic images to print from the laptop, through the printer being spooled through the desktop PC. In this case the more local bandwidth: (The amount of data that can be passed along a communications channel in a given period of time. ) that we have available the better so we will go with the 802.11g standard which supports up to 54Mbps as apposed to 802.11b which supports up to 11Mbps. Since most internal NICs will support 10Mbps, 100Mbps and 1000Mbps: (Gigabit, depending on the age of the equipment) the closest match for the wired LAN connection to the wireless 54Mbps capability will be 100Mbps and per our DSL modem documentation it supports this speed as well.

Now we can revise our requirements list:

• Two 100Mbps wired connections for the current desktop PC NIC (Network Interface Card) and DSL modem.
• Wireless connectivity compatible with the 802.11g standard supporting up to 54Mbps.
• We need a way to share the Internet connection between the desktop PC and the laptop.

Ok, now we have our requirements for network physical connectivity, speed and Internet connection sharing so now there’s just a couple of more things to cover. Lets start with the wireless network range requirements. There are several factors that will determine the network range including the power of the equipment, size and type of the antenna and any obstructions that might be within the data path. In this simple scenario we will be working inside of a 1900 square foot, single story home. We shouldn’t need any additional equipment (discounting any interference from other appliances) outside of the default antenna that comes with our wireless router to connect in most any room in the home. For special circumstances or for optimal signal strength a ceiling dome antenna or range extender could be used but for simplicity here we will just stick with the default equipment.

Now we can revise our requirements list once again:

• 100Mbps wired connection for the current desktop PC NIC (Network Interface Card) and DSL modem.
• Wireless connectivity compatible with the 802.11g standard supporting up to 54Mbps.
• Routing capability for Internet connection sharing.
• No need for any external antenna or range extender.

Finally, we need to determine our WLAN security requirements. Based on what you learned in the previous article we will apply some of that knowledge here. First off we want the ability to only allow the physical (MAC) addresses of our own devices to connect to our WLAN, this requires the MAC Filtering List functionality. Secondly we want our wireless network to be protected with the stronger 128bit WPA2 encryption to protect our clear text email and instant messages. Lastly for extra security on the perimeter of our network we want a built in firewall that performs stateful packet inspection. By supporting SPI the firewall will block incoming traffic from the Internet to our network but still allow return traffic from the Internet to our network if it was initiated from inside of our network.

Now we can revise our requirements list once again:

• 100Mbps wired connection for the current desktop PC NIC (Network Interface Card) and DSL modem.
• Wireless connectivity compatible with the 802.11g standard supporting up to 54Mbps.
• Routing capability for Internet connection sharing.
• No need for any external antenna or range extender.
• Built in SPI (Stateful Packet Inspection) firewall.
• Must support MAC address filtering.
• Must support 128bit WPA2 encryption.

That’s it, we’ve determined the requirements for our simple home based wireless LAN. Now all that’s left is to do is the research and ultimately the purchase. There will be lots of different brands of wireless routers on the market that support the requirements for our network so have your checklist handy while checking out the datasheets on each unit. After you find the group of units that fit your needs personal preference, warranty, availability and price will be the final determining factors.