The future of wireless networking architecture
Intelligence at the network edges
By Imran Akbar | Network World US | Published: 16:00, 10 November 2010
With ever more devices needing greater throughput for video and voice content, today's wireless hub-and-spoke network architecture is showing its age. What's needed is a wireless LAN (WLAN) solution capable of greater intelligence at the network's edge to optimise traffic flow without compromising security or quality of service and driving up cost.
The hub-and-spoke innovation was in routing traffic through, and enforcing security at, the wireless controller. However, the controller is now becoming the bottleneck for throughput and security enforcement as throughput needs rise. Trying to address this bottleneck using traditional WLAN solutions ultimately means an "either/or" trade-off: either a significant new investment in additional wireless controllers and wired switches or a greatly reduced QoS and user experience.
To take a step forward, what's needed is a "both-and" solution without compromise, one that helps you unleash the full advantages of your existing 802.11n investment. Such architecture could maximise network performance and traffic without compromising QoS for video and voice features, security, mobility or survivability, while at the same time minimising both capital and operational expenditures for a lower total cost of ownership (TCO).
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This requires a fundamentally different model: an architecture that provides more intelligent routing at the perimeter of the network than the centralised hub-and-spoke model. This can be achieved with a more intelligent perimeter, using smart, adaptive wireless access points to offload some of the higher order intelligence and functionality of the controller itself.
Distributed intelligence allows more of the on-site data flow to be routed internally on the edge of the network using the 11n access points, rather than sending that data to the wireless controller and back. It maintains the strength of the entire WLAN infrastructure, while increasing the ability of the "spokes" to communicate directly with one another along an optimal path, even prioritizing more critical data (such as VoIP and video) while providing full security and mobility services.
Not all 802.11n solutions are created equal, however. They can vary greatly in their range of capabilities. How well do access points interact with controllers for instance? How many controllers are needed? What are the power requirements? How does the survivability of the system compare?
A more adaptive, reliable and intelligent architecture takes factors like these into consideration. It leverages the network's distributed intelligence to help unlock the full value of 802.11n solutions so they can both deliver a better quality of experience and make IT budgets go further.
By having more intelligence in the access points, during outages these access points can also serve a bridging function to reduce latencies. Since security is as important to the organisation as solid network coverage and availability, it is important to make sure that any distributed architecture has enough application awareness to be self-healing without dropping VoIP calls and that it is able to deliver the same firewall capabilities as hub-and-spoke to avoid compromising QoS.
This helps maintain network services throughout outages, ensuring the organisation and its assets continue to benefit from continued local QoS prioritisation, authentication, security policies and direct routing as well as backhaul failover to 3G.