Cisco Cisco WAP4410N Wireless-N Access Point - PoE Advanced Security メンテナンスマニュアル

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Troubleshooting
WAP4410N Wireless-N Access Point with Power Over Internet Administration Guide
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A
The Cisco WAP4410N Access Point supports the following IPv6 
Applications:
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WEB/SSL
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SNTP
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PING6
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TRACE Route 
Q.
What is roaming?
Roaming is the ability of a portable computer user to communicate 
continuously while moving freely throughout an area greater than that 
covered by a single access point. Before using the roaming function, the 
workstation must make sure that it is set to the same channel number as the 
access point of the dedicated coverage area. 
To achieve true seamless connectivity, the wireless LAN must incorporate a 
number of different functions. Each node and access point, for example, 
must always acknowledge receipt of each message. Each node must 
maintain contact with the wireless network even when not actually 
transmitting data. 
Achieving these functions simultaneously requires a dynamic RF 
networking technology that links access points and nodes. In such a 
system, the user’s end node undertakes a search for the best possible 
access to the system. First, it evaluates such factors as signal strength and 
quality, as well as the message load currently being carried by each access 
point and the distance of each access point to the wired backbone. Based 
on that information, the node next selects the right access point and 
registers its address. 
Communications between end node and host computer can then be 
transmitted up and down the backbone.
As the user moves on, the end node’s RF transmitter regularly checks the 
system to determine whether it is in touch with the original access point or 
whether it should seek a new one. When a node no longer receives 
acknowledgment from its original access point, it undertakes a new search. 
Upon finding a new access point, it then re-registers, and the 
communication process continues.