There's a lot happening on your company's wireless network, and future wireless burdens are only going to get heavier, with more and more mobile devices and more bandwidth-heavy applications, such as voice and video, traversing the network. While the details are best left to your network admins, CIOs need to have a handle on future wireless options and technologies. In this webcast presentation, Shamus McGillicuddy, senior analyst for Enterprise Management Associates, explains enterprise wireless planning considerations for CIOs responsible for supporting mobile devices -- whether that of employees or customers -- on the network. Find out what the 802.11ac protocol will bring to the network, and why the next iteration of 802.11ac -- Wave 2 -- is such an important upgrade.
See the rest of this webcast presentation
Part 1: Determining enterprise networking strategy to support mobile devices
Part 2: Upgrading the wireless LAN
Part 3: Trickle-down effect on the wired network
Questions about this webcast presentation on enterprise wireless planning? Email [email protected].
Transcript - Enterprise wireless planning: Key considerations
Shamus McGillicuddy: Let's look at the wireless local area network [LAN]. You need to think differently about it today. The old way of doing Wi-Fi is over, and when I say 'the old way of doing Wi-Fi,' Wi-Fi used to be a nice-to-have technology. You'd have pockets of wireless coverage in conference rooms. You'd have best-effort access for guests who might want to access the Internet or maybe download a couple files from their own server somewhere. It was a low priority for network operations, which meant that if there were problems with accessing the wireless LAN, it was something that they would get to after the more critical things were taken care of.
Now, Wi-Fi is a primary network access layer for a lot of enterprises. Users access wireless from everywhere. Guests are often business partners who need Wi-Fi to collaborate with your employees or customers who want to use Wi-Fi within your retail establishments and so forth. Network operations teams need the infrastructure and the tools to support mobile workers, partners and customers moving forward.
So, continue to think differently. The new wireless local area network must cover the whole enterprise. Users are mobile within your environment; they're not just going to be sitting at their desks. They're not going to be obediently meeting and accessing wireless LAN services only from your conference rooms, for instance. They might be bumping into each other anywhere in your enterprise, taking out their mobile devices and needing them to work right then and there, and if they don't get access, their productivity is impacted.
Also, with that in mind, device and user density will challenge your infrastructure. Users congregate to collaborate, and they will do that wherever they feel comfortable, not where you have put your access points. They also have multiple devices. Device density will lead to airtime contention, meaning that devices will be competing for access to your wireless network. Now -- and think about this -- while the smartphone is sitting in your employee's pocket and they're perhaps using a tablet or laptop actively, that smartphone is probably still accessing your network from their pocket updating various applications on their device.
Wireless bandwidth needs to support demanding applications, too. You're going to see people using mobile video conferencing. Something as simple as FaceTime video chat on an Apple device will be hitting your Wi-Fi network. You'll have voice over Wi-Fi hitting your network, especially if that's a strategic technology for you; a lot of companies are cutting the cord on their voice. Large file downloads will hit you, and then you [have to] think about virtual desktop infrastructure perhaps.
So, let's look at the basics of wireless LAN and how you get started. Wireless LAN starts with the wireless access point, which is a radio device plugged into your Ethernet ports. It's usually ceiling-mounted or wall-mounted; it might be on someone's desk, although I would advise against that. You can have options for multiple device form factors with your access points. They come in indoor models or more ruggedized outdoor models, depending on where you want to provide wireless LAN services. They have multiple radio configuration options, which means the more radios inside, the more throughput and user density they can support. These are things you want your engineers to be thinking about as you are getting ready to design your wireless LAN infrastructure.
The central component of most LAN architectures is the wireless controller, which is typically a centralized appliance deployed in your data center. Access points rely on controllers to make forwarding decisions on new traffic flows. They're basically the management and control center for your wireless LAN. Access points will have limited functionality if they lose contact with that controller. So, some vendors will distribute the control plane for your wireless LAN in their switches, if they're a switch vendor, their access points, or into the cloud. This distributed control plane might add resiliency to your wireless LAN.
The third component of the wireless LAN is usually the management tools.
So, when you're getting started with looking at what your wireless LAN needs to be, you need to assess your needs. What do you have today? Identify legacy equipment that should be retired. You might have some 10-year-old wireless access points somewhere in your enterprise that you probably want to retire. And you want to identify installed infrastructure that can be incorporated into your new mobile strategy.
You want to perform a wireless site survey. This will involve wireless engineers assessing your facilities to see how wireless signals will act and behave within your physical space. This is typically done by either the professional services [staff] from your vendors, maybe a value-added reseller, or you might have in-house engineering talent that can take care of it. This will help you determine the number and placement and configuration of your access points that will provide the wireless coverage and the performance that you need.
You should also think here about whether or not you need rugged wireless LAN infrastructure. Outdoor Wi-Fi gear is usually weather-hardened to provide Wi-Fi service in outdoor spaces such as courtyards [or] campus areas if you're [in] a university setting. There are also specialized vendors that might cater to more harsh conditions, such as factory floors, cold warehouses [or] heavy vibration situations. If you're trying to outfit your airplanes, for instance, you might want to look at something that can handle turbulence.
Furthermore, identify potential wireless hotspots. Once you've gone past your site survey you want to think about how people behave in your enterprise. Are there places where people congregate? Meeting spaces [or] classrooms, for instance. A single access point might not be enough in that location.
Identify data-intensive applications that will stress your Wi-Fi. Make sure you have the bandwidth to support things like voice and video. And this is where you want to start thinking about, for the future, gigabit Wi-Fi speeds. They have arrived on the market, and they will serve your most-bandwidth-intensive applications on your wireless network.
So, gigabit Wi-Fi is here. This is a major transition in the industry. Your wireless LAN strategy should include gigabit Wi-Fi. Your current wireless LAN is probably sub-gigabit technology. Most wireless LANs deployed today are based on IEEE 802.11n, which is a Wi-Fi standard that has a theoretical maximum data rate of 600 Mbps, which is pretty fast, but it's not the fastest. Access points based on this standard operate in both a 2.4 GHz and 5 GHz radio spectrum, and that's important to think about. 2.4 GHz is a noisy radio spectrum that offers a lot of interference.
Gigabit Wi-Fi infrastructure is now mature. It's been on the market for a little while. Its IEEE standard is 802.11ac, and it can reach [a] theoretical maximum bandwidth of 1.3 Gbps, which is about as fast, if not faster, than what you might have your PCs plugged into today in your cubicles. Future versions of this standard will be multi-gigabit. And this technology offers less wireless interference and more user density.
So, let's look at gigabit Wi-Fi up close because this is critical. It's available today as Wave 1 technology; that's 802.11ac Wave 1. You'll see that if you're researching this online. It's a technology that offers less interference from things like Bluetooth, microwaves, cordless phones, because it operates only in 5 GHz, which is a quiet radio spectrum and it leaves the 2.4 GHz spectrum to legacy Wi-Fi devices. And that's a thing to think about strategically. It offers more bandwidth, too, because it uses wider channels in that radio spectrum, which means more throughput. So, you get 1.3 Gbps throughput, as I mentioned, versus the 600 Mbps maximum of 802.11n. That's a major difference when you're using something like mobile video conferencing. Trust me.
Later this year or early next year we'll see 802.11ac Wave 2, which has a maximum theoretical bandwidth of 7 Gbps. Enterprise use cases will see lower maximum bandwidths because this uses such wide channels that at the highest data rate that's going to be such a crowded radio spectrum that it's only going to work perhaps in home entertainment settings where you want to wirelessly connect your TV to HD video sources. But in an enterprise setting, you're still going to get multiple gigabits of speed.
Wave 2 is also going to give you more user density. This is important. It uses a technology called multi-user multiple input multiple output, or MU-MIMO, which allows access points to talk to two to four mobile devices simultaneously. Previous Wi-Fi standards have only allowed an access point to talk to one device at a time, which means the devices had to queue up and wait for the access point to be ready for them. Your users might perceive this as a slight delay, but when they stack up one after another you run the risk of having devices struggling to get a connection because there might be one or two slower, older mobile phones, for instance, connected to that access point downloading something sizable and the faster devices might be queued up behind it waiting for their chance. Now with MU-MIMO technology in Wave 2, you'll have two or four, depending on the configuration, mobile devices connecting simultaneously. It just means everyone's getting their data much faster.
There are some pitfalls with 802.11ac gigabit Wi-Fi that you need to think about and ask your engineers about when they're selling you on this concept. 802.11ac Wave 2 MU-MIMO has some downsides. It reduces the effective distance of an access point, and access points will need to be smart about when to use it and when not so they can get more range for people to load it further from the access point.
The wireless spectrum can also get a bit crowded. Because there are wider channels, they bump up against each other because those wider channels are still using the same [amount of] overall wireless spectrum so there's less space between them. Think of just larger streams of water going through the same pipe, or something. It can lead to co-channel interference, or crosstalk, between two radios, which would lead to things like dropped packets, which leads to applications and user sessions failing. So, make sure your engineers are smart about using wireless spectrum with these wider channels.
There are some investment protection things to think about when you're going mobile. 802.11ac infrastructure can coexist with 802.11n, so the gigabit Wi-Fi can live in 5 GHz and the sub-gigabit can live in 2.4 GHz. That kind of gives you two layers of network, where the 11ac serves your high-speed technologies, and then slower devices, like maybe old medical imaging technologies at a hospital, might be stuck in 11n until you're ready to upgrade those devices on the line-of-business side.
Then you have many Wi-Fi vendors offering investment protection in their access points. … For instance, most [802.11n] vendors offer access points with modular radio slots where you can later plug in a new radio module that upgrades it to an 11ac gigabit Wi-Fi device. Same thing with some of the early 11ac Wave 1 access points with modular radio slots. Some vendors will sell you at a later date a radio module that upgrades you to the Wave 2 technology and gives you multi-gigabit speeds in the future. [It] gives you a way to sort of gradually upgrade your technology.