Nortel 6220 User Manual page 150

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1. Why can CSU setup a radio connection to the APU?
Such situations are caused by various reasons as below:
- Mismatching between the radio setup parameter of APU and that of CSU
+ Radio Channel
+ Network ID (NWID)
+ WEP Encryption Key
- Radio Link Designing Problem(Link Distance, Antenna Direction and so
on)
2. How many CSU subscribers can connect to a single WLAN Cable Access
Point (APU Secure Data mode)?
Eight CSU subscribers can connect to a single WLAN Cable Access Point in
secure data mode.
3. How does the number of CSU Secure Data modes affect wireless
throughput?
As more CSU Secure Data modes are added, the APU Secure Data mode Base
Station mode is still able to effectively manage the throughput of the overall
wireless link. Just as on any shared medium, each station's throughput is
determined by the overall usage of the wireless link. The more stations
transmitting on the link at a time, the lower each individual station's throughput
goes. However, Secure Data mode performs in such a way that up to a point, the
more heavily loaded the network becomes, the higher the overall throughput
becomes.
For example, due to the intricacies of our Adaptive Dynamic Polling algorithms
and Secure Data mode 'fairness' principles, a single-user FTP session does not
use all of the possible wireless bandwidth. But when performing several
different transfers to and from different CSU Secure Data modes, the actual
overall bandwidth of the Secure Data mode network increases. In general, the
heavier a Secure Data mode network is loaded, the higher the total bandwidth
used becomes.
4. How do I check throughput?
Network throughput can be tested and analyzed using the Ping Fill test. This test
dynamically fills the network connection with ICMP Echo (ping) packets and
waits for the responses from the target station. Since each packet sent is echoed
back to the sender, this tests the overall wireless throughput in both directions.
Choosing the correct parameters is crucial to obtaining accurate Ping Fill test
results. The speed at which the target station responds to the ICMP Echo packets
is crucial to correctly assess the speed of the wireless link.
WLAN Cable Access Point 6220 CSU NTPM99CA Rel 2.0 Issue 5 Dec 2005