Implementing Wireless “Switches”
by Michael Disabato
Posted 4/2004; Published 10/2003

Abstract:

Now that Wi-Fi Protected Access (WPA) has resolved the known security vulnerabilities of wireless local area networks (WLANs), and the confusion over radio technology selection has been cleared up, many in the wireless industry have turned their attention to the architecture of WLANs and how they should be engineered and deployed. These thoughts have spawned several arguments within the WLAN segment.

The leading argument is about where the network intelligence should reside. Traditional systems put all the intelligence in the access point. This results in economies for smaller networks, but leads to significant redundancies in large networks.

The second argument concerning distributed intelligence is: If all the intelligence shouldn’t go in the access point, how much should? Most distributed system vendors only put the radio and enough intelligence in the access point to allow it to communicate with the central controller. “Enough” may mean a MAC-layer communications processor or a full IP stack with encryption functions.

The third argument has been about WLAN designs. Using radio frequencies (RF) at Layer 1 means giving up the deterministic nature of switched, wired networks. Further, mobility changes the delivery model for network services and forces the addition of new services to accommodate address and session management, security and policy enforcement.

In September 2002, Symbol Technologies attempted to resolve these issues with the announcement of its Mobius WLAN switch. Far from clarifying the issues, Symbol fired the first shot in a new war for the wallets of network managers who are considering WLANs. Seven start-ups and five established network vendors now are vying for a share of the WLAN switch market. Clearly, too many vendors are chasing too few dollars, and consolidation in this market is inevitable.

While the marketing hype about these devices continues, the most misleading concept is that they are truly wireless switches. Nothing could be further from the truth.

About the author:

Michael Disabato covers wireless technologies and mobility for Burton Group.

Please note: By downloading this information, you acknowledge that the sponsor(s) of this information may contact you, providing that they give you the option of opting out of further communications from them concerning this information.  Also, by your downloading this information, you agree that the information is for your personal use only and that this information may not be retransmitted to others or reposted on another web site.  Please encourage colleagues to download their own copy after registering at http://www.webtorials.com/reg/.