Enterprise WiFi Overview

 

The last 5 years of enterprise wireless LANs have enabled IT professionals to push high-availability techniques to the network edge, closer to users than ever before. By overlapping RF coverage areas from WLAN access points, you could provision redundant links to users and increase availability. There were two ways to do this – deploy fat APs with intricately customized configurations or connect managed APs to multiple WLAN controllers in “salt-and-pepper” configurations.

Unfortunately, as enterprise WLANs proliferated throughout the corporate enterprise to branch offices and remote locations, this legacy approach to high availability introduced massive complexities, proved very expensive, or was not even recommended by the manufacturer due to scaling difficulties.

 

Mission Critical Applications

Like aircraft navigation systems, network computing applications are an essential part of the communications infrastructure in virtually every business organization – from the largest global enterprises to small/medium enterprises.

Here are a few examples:

• Secure real-time access to a hospital patient’s medication history.

• Wi-fi based voice and paging systems, particularly those used in health care.

• Finance staff must be able to find and extract fiscal data to generate quarterly reports.

• Development engineers require access source code or design databases to build products.

• Access inventory information for just-in-time and quarter-end expenditure decisions.

• Cashiers at retail points of sale are required to perform credit and debit card transactions.

Because they are so vital to daily business operations, IT management has in the past been willing to tolerate the increased complexity and higher costs to just make sure that these mission-critical applications are highly available. As we shall see, there is another way that avoids the additional cost and complexity entirely.

 

Branch Office Operations

High availability is vital in branch offices. Remote sites serve a critical function that requires them to be self-sustaining – whether wired or wireless – in the wake of a loss in connectivity to centrally located corporate resources. For example, AAA servers in the corporate data center might require branch office users to be authenticated before they can access certain network resources.

While this approach is ideal for centralized administration, it puts branch office operations at risk if the WAN link to AAA servers in the corporate data center goes down. Furthermore, in distributed environments costs play a major role in weighing the risks/rewards of high-availability network designs because capital equipment expenditures are multiplied by the number of branch offices.

 

Large Public WiFi Networks

Wi-Fi networks in large open, public or rented spaces – such as in conference rooms, convention centers, concert venues and sports arenas – have huge peak demands, no easy wiring options and high expectations for “always-on” availability. If the network suffers from frequent failures and offers only sporadic availability, the negative impact on the host facility’s reputation can be viral and immediate.

Sufficient time is rarely available to diagnose and repair problems in these networks. Conferences, conventions, concerts and sporting events occur only for a few hours at a stretch. So in the case of public-space networks, a wireless solution that is always on and self-healing – and forgoes incremental costs to reap these benefits – can keep users happy and the host facility’s reputation intact.

 

Disaster Recovery Networks

With disaster recovery, it’s not so much a matter of if, but when. And when it happens, IT is always at the flashpoint trying to get things up and running. While few would argue that a data recovery plan is crucial, a network recovery plan to access that data – wired and wirelessly – is often treated as an afterthought. As a result, the cost of network recovery preparedness must be low or it just won’t happen.

In the wake of an outage, network design – and the degree to which you’ve included high-availability and resiliency – will determine if a network and AAA infrastructure is accessible, intermittently accessible or completely inaccessible. These failures can trigger multiple downstream problems at headquarters, a remote site or multiple sites, and you must be able to get the network back online quickly and efficiently wherever you happen to be.

 

In Summary

Today’s wireless LANs are deployed to support a wide range of business applications ranging from mission-critical applications like voice and transaction processing to simple convenience applications like guest internet access.

As a result, traditional WiFi solutions rarely provide the performance required to drive today’s Enterprise applications.