Appendix C Wireless LANs
NWA3000-N Series User’s Guide
322
hidden node. Both stations (STA) are within range of the access point (AP) or
wireless gateway, but out-of-range of each other, so they cannot "hear" each
other, that is they do not know if the channel is currently being used. Therefore,
they are considered hidden from each other.
Figure 130
RTS/CTS
When station
A
sends data to the AP, it might not know that the station
B
is
already using the channel. If these two stations send data at the same time,
collisions may occur when both sets of data arrive at the AP at the same time,
resulting in a loss of messages for both stations.
RTS/CTS
is designed to prevent collisions due to hidden nodes. An
RTS/CTS
defines the biggest size data frame you can send before an RTS (Request To
Send)/CTS (Clear to Send) handshake is invoked.
When a data frame exceeds the
RTS/CTS
value you set (between 0 to 2432
bytes), the station that wants to transmit this frame must first send an RTS
(Request To Send) message to the AP for permission to send it. The AP then
responds with a CTS (Clear to Send) message to all other stations within its range
to notify them to defer their transmission. It also reserves and confirms with the
requesting station the time frame for the requested transmission.
Stations can send frames smaller than the specified
RTS/CTS
directly to the AP
without the RTS (Request To Send)/CTS (Clear to Send) handshake.
You should only configure
RTS/CTS
if the possibility of hidden nodes exists on
your network and the "cost" of resending large frames is more than the extra
network overhead involved in the RTS (Request To Send)/CTS (Clear to Send)
handshake.
If the
RTS/CTS
value is greater than the
Fragmentation Threshold
value (see
next), then the RTS (Request To Send)/CTS (Clear to Send) handshake will never
occur as data frames will be fragmented before they reach
RTS/CTS
size.
Note: Enabling the RTS Threshold causes redundant network overhead that could
negatively affect the throughput performance instead of providing a remedy.
Summary of Contents for NWA-3160
Page 2: ......
Page 14: ...Table of Contents NWA3000 N Series User s Guide 14 ...
Page 15: ...15 PART I User s Guide ...
Page 16: ...16 ...
Page 30: ...Chapter 1 Introduction NWA3000 N Series User s Guide 30 ...
Page 48: ...Chapter 2 The Web Configurator NWA3000 N Series User s Guide 48 ...
Page 54: ...Chapter 3 Configuration Basics NWA3000 N Series User s Guide 54 ...
Page 72: ...Chapter 4 Tutorials NWA3000 N Series User s Guide 72 ...
Page 73: ...73 PART II Technical Reference ...
Page 74: ...74 ...
Page 82: ...Chapter 5 Dashboard NWA3000 N Series User s Guide 82 ...
Page 146: ...Chapter 11 User NWA3000 N Series User s Guide 146 ...
Page 164: ...Chapter 12 AP Profile NWA3000 N Series User s Guide 164 ...
Page 170: ...Chapter 13 MON Profile NWA3000 N Series User s Guide 170 ...
Page 192: ...Chapter 14 Certificates NWA3000 N Series User s Guide 192 ...
Page 226: ...Chapter 15 System NWA3000 N Series User s Guide 226 ...
Page 252: ...Chapter 17 File Manager NWA3000 N Series User s Guide 252 ...
Page 262: ...Chapter 18 Diagnostics NWA3000 N Series User s Guide 262 ...
Page 264: ...Chapter 19 Reboot NWA3000 N Series User s Guide 264 ...
Page 266: ...Chapter 20 Shutdown NWA3000 N Series User s Guide 266 ...
Page 284: ...Chapter 22 Product Specifications NWA3000 N Series User s Guide 284 ...
Page 318: ...Appendix B Importing Certificates NWA3000 N Series User s Guide 318 ...
Page 372: ...Appendix D Open Software Announcements NWA3000 N Series User s Guide 372 ...
Page 378: ...Appendix E Legal Information NWA3000 N Series User s Guide 378 ...