Wireline: Standalone or "Fat"



Historically, this was the first wireline architecture for wireless. In a standalone AP network, each access point is entirely independent of the others.
In the consumer space, only standalone access points are sold today. However, the first enterprise-grade access points also fell into this style. Each access point has its own management system—whether simple or complex, web-based or command line interface (CLI). The access points each maintain their own configurations, connect to outside services (especially Remote Authentication Dial In User Service, or RADIUS) on their own, and generally have no cooperation with any neighboring access point, even from the same vendor.
Most important for mobility, each access point is its own bridge, connecting to the wired network immediately at its Ethernet port, without any tunneling. This means that the access point offers very few or no mobility services. If two access points are connected in different subnets, then the client is required to get a new IP address after a handoff, usually resulting in a dropped call. To avoid this effect, administrators are forced to distribute the subnet to every access point—for multiple-Virtual LAN (VLAN) networks, this means that each access point must be trunked back, across the access and distribution layers of the wired network.
These access points can be managed using centralized network management tools, and vendors that offer them incorporate Wi-Fi-specific functionality to attempt to mitigate the complexity of managing thousands of individual access points. The management tool may be software, installed on a server, or it may come as an appliance.
Most standalone access points are limited to the typical one or two radios. However, one manufacturer makes multiple-radio standalone access points, which they call arrays.This technology uses sectorization to reduce the coverage pattern for each radio, allowing over a dozen radios to be packed into the larger version. The goal here is for density: if one radio can support a certain number of clients, then 12 radios should support 12 times that amount, all with one cable pull. Understandably, wireless arrays are significantly larger than other access point types.

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