Proposed standard eases WLAN management

In enterprise-class 802.11 deployments, network control is limited to the infrastructure, such as wireless switches and access points. Network administrators have little control over wireless client devices such as laptops, PDAs and voice over wireless phones. Uneven distribution of wireless clients on access points typically results in heavily unbalanced networks that suffer bandwidth and access problems.

As a proposed standard for wireless network management, IEEE 802.11v will provide important and efficient mechanisms to simplify network deployment and management. The standard defines procedures by which a wireless infrastructure can control key parameters on wireless client adapters, such as identifying which network and/or access point to connect to.

Work began on the standard early this year, and the IEEE expects to finalize it in early 2008. There probably will be early implementations of 802.11v in 2007. Most 802.11v support might be implemented in software, for new products and to upgrade existing WLAN gear. For the standard to be ef"fective, clients (WLAN cards and adapters) and infrastructure (access points and WLAN switches) will need to support it.

Wireless client control, network selection, network optimization, and statistics retrieval and monitoring are among the capabilities proposed for 802.11v.

Wireless client control involves several aspects. Load balancing distributes wireless clients among access points based on their loads. Today this is achieved by preventing clients from connecting to overloaded access points or terminating client sessions on existing access points. But these actions can disrupt client sessions. 802.11v envisions making load balancing transparent to users by pointing clients to access points with available bandwidth and resources.

Time spent bringing up client devices also affects deployments. With 802.11 a client device joins a network identified by the Service Set Identifier (SSID). There is no mechanism to automatically tell a client device what networks it should connect to without manually configuring the client device with the SSID and security credentials. But with 802.11v capabilities are being proposed to enable secure client configurations from the infrastructure. This will significantly cut deployment time in large-scale networks.

Schemes that will save significant battery life on low-power devices such as voice-over-wireless-LAN phones also are being considered for 802.11v. Any radio can host more than one logical wireless network. And each local network has management traffic. There are proposals in 802.11v that will minimize management traffic.

802.11 defines several SNMP-type Management Information Bases (MIB) for control and provisioning of a variety of attributes on the client side, such as operational data rates and power management schemes. The current 802.11 specification does not provide functionality to control MIBs over the air from the network infrastructure. 802.11v will provide mechanisms to control MIBs on the client side and will simplify client configurations.