Simplify the management of your wireless network plus give users advanced mobility services with this one device.
Small Businesses have embraced Wireless LAN for a number of reasons -- initially it offered wireless access and connectivity to various devices but now it has become an integral part of business today, not only boosting employee productivity but also becoming a viable alternative to wired (Ethernet-based) access to the network. As the number of clients using wireless infrastructure continues to increase, so does the need for continuous wireless coverage, wireless network uptime and centralized management and monitoring.
Over a period of time as your business grows and you hire new employees and add new access points or move to new buildings or floors it becomes increasingly difficult to manage, configure your wireless infrastructure. And if you have more than two or three wireless access points, managing each of them separately is a time-consuming task.
These 5 building blocks will help ensure your network supports your business today and in the future.
If you’re just beginning to build your network for a fledgling small business or you’re expanding the network of a more established smaller company, you should plan your network with an eye toward preparing your business for growth. Your network should be a secure, reliable foundation; one that’s flexible and can adapt to the changing needs of your business as well as give you a competitive edge.
One of the key tenets of engineering is to reduce complexity, but in doing so it is important to understand the implications. While we might try to view one technology as it relates to another to help us simplify the details, it is important that we recognise how and where they differ.
Case in point.
When it comes to wireless networks, I often talk about how there are two questions I dislike being asked more than any others:
How many clients can connect to an access point?
What is the maximum range of an access point?
The reason is that I believe they are the wrong questions. They are being asked from perspective of someone trying to relate to a wireless network as if it were a wired network. What they are really asking is “how many switch ports do I need to cover this area?”
But wireless networks are not switched networks. While each connected device in a wired network has its own physical cable, and thereby its own gigabit Ethernet link, in a wireless network, every device connected to a particular access point shares the same RF spectrum, the same total available bandwidth.
For a standard access point in today’s deployments, that means a maximum total bandwidth of 144Mbps on the 2.4GHz band with a 20MHz channel and 300Mbps on the 5GHz band with a 40MHz channel using channel bonding.
But that is an over simplification.
Those aggregate bandwidths assume each client is connected at the highest available data rate. As we increase range, however, the data rate decreases, thereby reducing the overall channel utilisation. Therefore, with fewer access points, we are not just sharing a limited amount of bandwidth with more clients, but we are actually reducing the total available bandwidth.
Interference, particularly as access points cover larger areas, becomes an even greater issue. An increase in the signal to noise ratio leads to a decrease in the maximum sustainable data rate. This again reduces the overall channel utilisation. The key here is that a wireless network’s ability to not only detect, but where possible mitigate interference is critical to its ability to sustain higher data rates and maximise the total available bandwidth in each cell.
All this assumes that the wireless clients connecting to the network are even capable of supporting those high data rates.
Most smartphones on the market today support only 802.11g in the 2.4GHz band, meaning that at most they can support 54Mbps.
Newer devices, such as the iPhone 4, support 802.11n, but only in 2.4GHz, and only with a single antenna, limiting them to a single “spatial stream”—in simple terms that means the maximum data rate they can support is 72Mbps.
This applies to tablet devices as well. While the new iPad2 supports 802.11n in both the 2.4GHz and 5GHz band, it too is limited to a single spatial stream. The Cius goes one step further with support for channel bonding in 5GHz, increasing the maximum data rate to 150Mbps.
Interestingly, we are now starting to see new access points enter the market using Atheros’ first-generation silicon supporting three spatial streams. While this increases the maximum data rate in the 5GHz band to 450Mbps, as we have just seen, this will have no impact on the multitude of mobile devices given their single spatial stream limitation.
Three spatial streams represents a key milestone for the 802.11 standard, and will become increasingly important over the next 2 to 3 years as battery technology improves and wireless chipsets incorporate better power saving designs. Of course, by that time we will be looking at access points supporting four spatial streams and 600Mbps—and again, be waiting for the mobile devices to catch up.
As we look to support these many different mobile devices entering the market today along with their high bandwidth applications, clearly the two key areas we must consider in our wireless network designs are access point density to control cell sizes, and interference detection and mitigation capabilities to ensure that we maximise the channel utilisation in each cell.
And so, I’d like to propose two different questions to consider at the start of a wireless deployment:
How many different devices do you expect to connect to the wireless network?
And what are the applications that will run across the network and what are their associated bandwidth requirements?
Wireless and wired networks fundamentally differ at the physical layer. While its not necessarily important to understand the details of RF communications, it is important to understand the implications.
So here we are, in the middle of March Madness. Lots of people that don’t normally follow college basketball, but still a great social environment and an opportunity to get together and pretend we know the teams we all picked in our brackets. Sometimes we pick based on “loyalty” and other times there are other reasons. We all have various “borders” we deal with every day.
So, bring onBorderless Networks. In the manufacturing area we still tend to think of a “border” between the factory and the business. After all, how can those people in the front office know what we need in the factory, right? Well, that separation gets smaller and smaller every day. Why? Because we’ve blurred the border. Sure, there are appropriate firewalls and security between the various layers. But every day we run into people that tell about needing data from the plant, from the machine, from the supplier, from the sales force, from the channel, from the customer. And sometimes we’re not in the office, we may be at home, at a different supplier, in an airport, at a concert or ball game with our kids.
The point becomes, there is data there and I am not there but I need to make a call and affect my plant productivity or answer a question from my CEO because there is a big opportunity or a major customer disappointment about to happen.