WESM zl Management and Configuration Guide WT.01.28 and greater

3-42

Radio Port Configuration

Considerations for Enabling Client Roaming

A mobile station may roam back and forth between several RPs. Ideally, such roaming

is hidden from wireless users, who do not need to know when they connect to a new

RP. They simply want their applications to continue functioning smoothly.

A station itself determines when it needs to roam (typically, in order to associate to

a radio with a better signal). However, your wireless network infrastructure should

support roaming. When planning roaming, you must consider the Physical Layer,

Data Link Layer (Layer 2), and Network Layer (Layer 3) of the Open Systems

Interconnection (OSI) model.

At the Physical Layer, most wireless stations roam seamlessly as long as your RP

radios provide seamless coverage. Generally, you should deploy RPs so that their

coverage areas overlap: stations should be able to roam between RPs without losing

the signal.

Note When the coverage areas of 802.11b/g radios overlap significantly, remember to set

the channels to non-interfering channels:

■ 1, 6, and 11

■ 1, 7, and 13

See “Configuring Radio Settings for a Particular Radio” on page 3-29 for more

instructions on setting a radio’s channel.

While a detailed discussion of wireless network design is beyond the scope of this

management and configuration guide, you should understand that the size and pattern

of an RP radio’s coverage depends on several factors, including:

■ the radio’s power level

The higher the power level, the larger the coverage area. An external antenna

raises the power level (to the degree that you may need to manually lower the

radio’s power in order to comply with your country’s regulations). See “Setting

the Desired Radio Power” on page 3-14 for more information on configuring

this setting.

Setting the power level lower than the maximum can help you provide seamless

coverage. Place RPs more closely together and configure self healing, as

described in “Network Self Healing” on page 12-88 of Chapter 12: “Wireless

Network Management.”