Building the perfect, virtual wireless network

Every innovation in networking has had one main goal – to better connect users with applications. In the past 30 years the way people use applications has changed profoundly, initially with the arrival of the personal computer and now with the mobilisation of communication, information access and cloud applications.

Organisations have been built around connecting users to applications on the PC. Mobility is changing everything, from infrastructure to application to devices. Legacy architectures based on Ethernet switching at the network edge are on end-of-life notice.

Users have embraced mobile modes of operation and it is now up to IT to optimise for mobility and drive its direction to achieve performance goals. Thirty years ago, users drove productivity through terminals connected to mainframe applications. These networks were built as a single, “flat”, bridged architecture that carried IBM SNA (Systems Network Architecture, IBM’s mainframe network standard) traffic from the user to the mainframe.

The PC revolutionised the user-operating model and IT faced significant adjustments in connecting users to applications instead of mainframe hardware.

The evolution continued with early wireless local area networks, usually deployed as a convenience to employees and corporate visitors. Legacy WLAN architectures built on microcellular wi-fi access points were designed to connect laptops to the network. Wireless notebooks are simply wireless devices connected to the network. Users still sit at a desk or in a conference room and work the same way they would on a wired network.

True mobility is more than just wirelessly connected devices. Mobility lets users move while they work and communicate, which completely changes how users connect to applications.

Today’s mobile devices are being joined in the enterprise by devices that are not limited to interaction and direction from human users – they conduct machine-to-machine communication over the wi-fi network. These devices are optimised for conducting business while in motion and delivering a superior user experience.

IT is expected to adapt to the new user experience and optimise the network for mobility.

Difficulties are created for the IT department because the Ethernet-free devices are using cloud applications and unified communications applications which require support for real-time video and voice. Mobile users require networks that support high speed, high user density, and high quality of service without wiring.

The architecture in the PC era was never designed to handle the post-PC era of computing with the ubiquitous mobility demanded by today’s users. With mobile applications and devices predominating, and the rapid adoption of cloud applications, access networks no longer need the high switching power required by PC architectures.

The network design tenets of the past 20 years called for IT architects to design access layers by provisioning anywhere from two to four Ethernet switch ports a desk. As organisations increasingly go wireless, access switches are underused, taking more space and consuming more resources than their workload justifies.

The first step in preparing the network for transition is switch consolidation. This is the process of more efficiently using existing switches to support a mobile environment, while reducing the total number of wired switches or ports that organisations’ need.

It also reduces the IT departments reliance on functionality built into Ethernet edge switches and pushes that responsibility to the centralised wireless system that seamlessly integrates with the datacentre.

Once switches have been reduced, reused, or recycled, IT architects can begin to choose areas appropriate for moving to an all-wireless edge.

Traditional microcell WLAN architectures were designed to complement wired infrastructures implemented for stationary users. Ultimately, the guiding network design principle is to maintain a limited number of users an access point and as long as this condition is met, service should be fine.

With truly mobile users it is possible and easy to design areas where there is consistently a crowd of users but no one can predict when or where that crowd will move next. The only answer is to assume the crowd is everywhere and overbuild everything.

Virtualisation has transformed almost every part of the network architecture including changing the premise of WLAN design to create an access architecture designed

for mobility. Virtualised wireless technology pools all available wireless resources and partitions it to create wireless environments for every device. Each device has a virtual port provisioned with the processing power, quality of service and security required for that device.

As the device moves, its environment moves with it so the device performs exactly the same, regardless of whether it’s stationary or mobile.