Wi-Fi roaming is often a tumultuous subject. The crux of the issue is, with Wi-Fi the roaming decision is left to the client.
In the recent years, there have been great strides in improving Wi-Fi roaming with the creation of standards-based roaming technologies. Cisco first pioneered fast roaming many years ago with CCKM (Cisco Centralized Key Management), which was the foundation for 802.11r. 11r which was ratified by the IEEE in 2008, allows for fast roaming, even on a secure 802.1X SSID. With 802.11r it is possible to roam without disruption during a voice or video call.
While client support of 802.11r is largely lacking in the laptop space, there is large support in the smartphone realm. Apple iOS devices have supported 11r since iOS 6 (http://support.apple.com/kb/HT5535). The recent Samsung smartphones, such as the Galaxy S4, S5, and Note 3, also support 11r.
Note: Some non-802.11r clients can react adversely when connected to an 11r WLAN. The current recommendation from Cisco is to have a separate WLAN for 802.11r clients.
802.11k is another amendment from the IEEE that helps to improve roaming. 802.11k provides a whole slew of information to the client, which allows the client to understand the RF environment and make an informed roaming decision. This information can include channel load and AP neighbor lists.
11r and 11k help, however, that does not mean the infrastructure is irrelevant in the roaming picture. With the help of a model train, we did some testing to figure out just how much impact the infrastructure could have. We compared Cisco to one of our competitors, whom we will call Vendor A.
This video summarizes the results and shows the train in action, or continue reading for more details:
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Tags: 11r, 11x, 802.11, 802.11k, 802.11r, 802.11x, access point, AP, channel, channel load, client, dbm, device, infrastructure, rf, roam, roaming, roaming decision, RRM, SSID, standards, statistic, technologies, technology, transit power, video, Voice, wi-fi, wifi, wireless, wlan
Everybody’s talking about 802.11ac, but we’ve sensed some confusion for next steps as far as how CIO’s and IT organizations should be approaching the new standard.
Should I move to 802.11ac?
You’re probably thinking: Chris, you’re a leader at Cisco, of course you want me to migrate to 802.11ac. That, my friends, is where you are wrong. There is no simple answer to the question of whether you should move your network to 802.11ac. Here’s my simple rule of thumb:
There is no premium for 802.11ac from Cisco. If you are deploying new Access Points’s today, you should be buying 802.11ac. If you’re not buying, you are probably satisfied with your network and how it will handle the growth of more and more clients associating with your network and the bandwidth demands that come with that client demand. If you feel you have a plan to handle this demand, then you are one of the few that can pass on 802.11ac.
That said, there is a strong ramp up for Cisco 802.11ac products in the market, the AP3700 is the fastest ramping access point in our history and we have yet to see if the AP2700 will claim that crown in the coming months. ABI Research estimates that currently 50% of new device introductions are 802.11ac enabled, a statistic expected to increase to 75% by the end of 2015. This is enough proof of the overwhelming interest in adding the benefits of 11ac to networks. Let’s take a step back and consider the basics of why people are moving to the new standard.
Today, everything is about getting what we want, when we want it. Instant gratification. It’s not just the millennials—we’ve all been conditioned to expect things within seconds. Could you imagine the days pre-Internet if you had the capability for on-demand movies? Read More »
Tags: 11ac, 11n, 802.11, 802.11ac, 802.11n, access point, AP, bandwidth, battery life, CIO, Cisco, client, consumer, dell'oro, deployment, device, education, End User, GHz, gigabit, HD, HDX, high density, IEEE, IT, laptop, macbook, mbps, Mhz, migrate, migration, network, networking, optimization, performance, retail, rf, Scalability, scalable, smartphone, spectral optimization, spectrum, standard, technology, university, visibility, wi-fi, wifi, wireless, wlan
Technische Universität Darmstadt, usually known as TU Darmstadt is a research university based in Germany. It was founded in 1877 and over the last 137 years has grown to be among the largest and most prestigious public universities in Germany serving over 25,000 students per year. It is the alma-mater to many world-wide leaders from Nobel prize winners, a CEO of a fortune 500 company, a president of a country and multiple World Robocup champions.
No wonder, they have a reference from Albert Einstein!
In 2009 TU Darmstadt embraced BYOD with the 5508 Series Controller managing the 1140 802.11n Access Points. Recently we talked to Thomas Vogel, the Head of Network Group and Andreas Liebe, the Network Services Manager who have over 15 years of experience managing WLAN environments. In this blog, we will describe some of the details of WLAN deployments using the 3850 Series Switch and the 5760 Series Wireless LAN Controller to address the new requirements in the school environment. Read More »
Tags: 3850, 5760, 802.11, 802.11ac, 802.11n, access, access point, account, AP, App, application, authorized, AVC, bring your own device, buildings, byod, Cisco, client, controller, Converged Access, darmstadt, deployment, devices, employee, encrypted traffic, environment, frankfurt, Germany, infrastructure, IPv6, LAN, management, network, policy, prime, Prime Infrastructure, requirements, research, school, security, services, standard, switch, technische, technology, trend, TU, TUD, unified access, Universität, university, user, visualize, wi-fi, wifi, wired, wireless, wlan
We live in amazing times, ask anyone who ever had to look up a phone number in a phone book. In the past this was the only way you could find the number to your favorite restaurant if you wanted to make a reservation. Today, all we need to do is reach into our pocket or purse and grab our mobile device, open an application and in a few seconds (not minutes) we have the phone number. Not only that, but we can see the menu and make a reservation right from the device. Over time we have become dependent on carrying the world (both personal and professional) in our pocket. With mobility, we are always on, always connected: nothing—whether it’s your team’s latest score or that email from a vendor you need to send to your boss—is more than a quick search away.
What once seemed unfathomable, this way of always being connected is now commonplace. However, as the application developers sit and think of the next killer app, the IT team has to make sure the network can not only support this new app, but also assure the performance meets the higher and higher demands of new apps. This requires the network to be more application-aware. And the reality is that more applications that require higher network performance are coming at a faster rate. Add to it new devices that use these applications are becoming accessible to everyone. On top of that, the people that use these applications and devices are becoming more demanding in terms of reliability and experience. So what is an IT person to do?
“We were ahead of the times,” says Joseph Tufano, VP and CIO of St. John’s University. “But times have changed. You see it everywhere: for example, if you go to a basketball game on campus, and there’s a timeout, everybody is using their mobile devices.”
IT is always working to increase the wireless performance of the network. However, as more bandwidth becomes available, users increase their usage and consume that bandwidth. Read More »
Tags: #80211ac, 802.11, 802.11ac, access point, App, application, bandwidth, campus, data, data rate, density, design, device, environment, gigabit, healthcare, infrastructure, IT, mobile, mobility, network, performance, standard, wi-fi, wifi, wired, wireless
Now that US tax day is over, we in the wireless field can get back to focusing on P1: optimizing and maintaining network performance. Keeping your network in good shape is like gardening: if you don’t pull out the weeds, it’ll never look as good as it could. My friend Jim Florwick detailed the gory bits of the 802.11b penalty with its awful lag in efficiency and absolute waste of spectrum. I write today to help give you the steps to act on Jim’s order to stop the madness.
I liken this process to a memorable scene from Monty Python: You must “Bring out yer dead.” However much the first standard insists it’s still alive, let’s all be honest with ourselves: 802.11b is dead.
In memoriam of the first amendment to the IEEE 802.11 wireless networking standard hailing all the way since 1999, 802.11b was superseded by 802.11a and g in 2003 which are much more efficient. 802.11n was available in draft form in 2007 and was ratified in 2009 while 802.11ac was ratified last September. A few years from now we should be planning the wake for 802.11a and 802.11g as well.
Now is the right time to bury 802.11b and reduce the drag on your network. Let’s be real: there is a reason cyclists are not allowed on the freeway, and an 802.11b device will slow everyone down. Here are 5 easy steps for eradicating your network of 802.11b and getting on your way towards higher speed wireless:
STEP 1. Identify any 802.11b devices on your network
All of the latest Wi-Fi connecting devices are 802.11a/b/g/n capable. So how do you hunt down the 802.11b-only devices? You’ll be looking for older laptop and mobile clients (mostly before the year 2005).
Cisco Prime Infrastructure makes this easy for you with a report on clients by protocol. It will look like this:
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Tags: 802.11, 802.11ac, 802.11b, adapter, Cisco, clients, computer, controller, data, device, gigabit, high density, LAN, legacy, mbps, mobile, mobility, monty python, network, optimize, parameter, performance, phone, rate, smartphone, Speed, tablet, tax, technology, USB, wi-fi, wifi, wireless, wlan, WLC