Make sure your wireless LAN can support the growing number of mobile devices and the increase in complex data traffic
A wireless network delivers several advantages for small businesses: convenience (no wires!), mobility (access the network from anywhere), and cost (wireless is cheaper to set up and reconfigure than a wired LAN), among others. If you’re already a wireless user and are using it for your small business, you’ll want to take steps to manage and improve the performance. After all, the amount of complex data being transferred over networks today demands high performance—not to mention the proliferation of various mobile devices relying on your wireless network.
Research shows that, in recent times as the number and type of mobile devices have exploded, wireless network performance has become more critical than ever. For instance, IDC recently forecast that shipments of applications-capable, non-PC mobile devices (e.g., smartphones, media tablets) will outnumber PC shipments in the next 18 months and that 25 billion mobile applications will be downloaded in 2011—that’s up from 10 billion in 2010.
How can you maximize wireless performance? We recommend concentrating on three areas: performance, coverage, and security.
- Replace old client technology: If you’re still using an 802.11b device, bite the bullet and shut it down—it’s just too slow and drags down network performance. Most 802.11b-only clients are being phased out in favor of 802.11g or 802.11a/g/n, so even disabling the lower 2.4GHz data rates on the WLAN will help. When replacing an older client device with one that supports 802.11n, make sure it uses MIMO chipsets, like the Cisco Aironet 1140/1260 Series Access Points, which will yield better performance on your network.
- Increase frequency: Wireless devices operate in two unlicensed frequencies—2.4GHz and a range of 5GHz frequencies. The 5GHz spectrum is less congested and offers eight times the number of channels as the 2.4GHz band. If you have dual-band devices accessing your network, such as iPads, make sure they’re connecting to the 5GHz frequency.
- Mitigate interference: Remember that walls, cubicles, metal elevator shafts can all affect a wireless access point’s range . You can also experience RF interference due to microwave ovens, cordless telephones, Bluetooth devices, wireless speakers, and other such devices. Cisco’s spectrum analysis tool CleanAir can be helpful if you have a lot of potential obstacles—it detects and automatically mitigates RF interference by configuring the wireless network around the interference source.
- Fill holes: Wireless coverage is finite—each access point covers up to 3,000 square feet . A good rule of thumb is 15 to 20 users per each access point for data, 8 to 12 for voice. Also, access points get better coverage when installed on the ceiling.
- Strengthen signals: If it’s unlikely you can replace older client wireless adapters with 802.11n, there is a way—using RF beam forming technology —you can focus your wireless network’s signal strength toward older 802.11a/g clients whenever they come on the network.
- Authenticate mobile devices: Certain mobile devices support a variety of 802.1x authentication methods and most automatically select the correct 802.1x method for their wireless SSID. The most common authentication method is a user name and password, but more sophisticated authentication methods require digital certificates, creating configuration profiles and sending them to mobile device users.
- Encrypt your wireless network: Encryption makes it difficult for hackers to break in and use your wireless network, access your data, and do other malicious things. The two types of encryption are WEP and WPA with AES, which is more secure. Most wireless access points support both WEP and WPA standards, but not all client devices support AES, which requires a dedicated chip. Make sure that AES is turned on in your network and that your clients and mobile devices are set to select AES, if that option is available.
- Segment your network with VLAN: A virtual local area network, or VLAN, is a way of segmenting your network so that employees access only the resources they need rather than having access to everything on the network. You may consider putting your wireless network in its own VLAN if you have more than 200 devices accessing your network or if you’re experiencing a lot of traffic, or you have a group of users who need more security or who are running the same applications.
What steps have you taken to improve a wireless network plagued by poor performance?