12. Wireless Network Glossary
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AirLive AP60 User’s Manual
802.11i
The IEEE standard for wireless security. 802.11i standard includes TKIP, CCMP, and
AES encryption to improve wireless security. It is also know as WPA2.
802.1x
802.1x is a security standard for wired and wireless LANs. In the 802.1x parlance, there are
usually supplicants (client), authenticator (switch or AP), and authentication server (radius
server) in the network. When a supplicants request a service, the authenticator will pass
the request and wait for the authentication server to grant access and register accounting.
The 802.1x is the most widely used method of authentication by WISP.
Adhoc
A Peer-to-Peer wireless network. An Adhoc wireless network do not use wireless AP or
router as the central hub of the network. Instead, wireless client are connected directly to
each other. The disadvantage of Adhoc network is the lack of wired interface to Internet
connections. It is not recommended for network more than 2 nodes.
Access Point (AP)
The central hub of a wireless LAN network. Access Points have one or more Ethernet
ports that can connect devices (such as Internet connection) for sharing. Multi-function
Access Point can also function as an Ethernet client, wireless bridge, or repeat signals from
other AP. Access Points typically have more wireless functions comparing to wireless
routers.
ACK Timeout
Acknowledgement Timeout Windows. When a packet is sent out from one wireless station
to the other, it will waits for an Acknowledgement frame from the remote station. The
station will only wait for a certain amount of time, this time is called the ACK timeout. If the
ACK is NOT received within that timeout period then the packet will be re-transmitted
resulting in reduced throughput. If the ACK setting is too high then throughput will be lost
due to waiting for the Ack Window to timeout on lost packets. If the ACK setting is too low
then the ACK window will have expired and the returning packet will be dropped, greatly
lowering throughput. By having the ability to adjust the ACK setting we can effectively
optimize the throughput over long distance links. This is especially true for 802.11a and
802.11g networks. Setting the correct ACK timeout value need to consider 3 factors:
distance, AP response time, and interference. The AP60 provide ACK adjustment
capability in form of either distance or direct input. When you enter the distance
parameter, the AP60 will automatically calculate the correct ACK timeout value.
