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Appendix B Wireless LANs
VMG5313-B10A/-B30A Series User’s Guide
364
Figure 190
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.
Fragmentation Threshold
A
Fragmentation Threshold
is the maximum data fragment size (between 256 and 2432 bytes)
that can be sent in the wireless network before the AP will fragment the packet into smaller data
frames.
A large
Fragmentation Threshold
is recommended for networks not prone to interference while
you should set a smaller threshold for busy networks or networks that are prone to interference.
If the
Fragmentation Threshold
value is smaller than the
RTS/CTS
value (see previously) you
set 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.
Summary of Contents for VMG5313-B10A
Page 15: ...15 PART I User s Guide ...
Page 16: ...16 ...
Page 32: ...Chapter 2 The Web Configurator VMG5313 B10A B30A Series User s Guide 32 ...
Page 40: ...Chapter 4 Tutorials VMG5313 B10A B30A Series User s Guide 40 ...
Page 71: ...71 PART II Technical Reference ...
Page 72: ...72 ...
Page 78: ...Chapter 5 Network Map and Status Screens VMG5313 B10A B30A Series User s Guide 78 ...
Page 106: ...Chapter 6 Broadband VMG5313 B10A B30A Series User s Guide 106 ...
Page 162: ...Chapter 9 Routing VMG5313 B10A B30A Series User s Guide 162 ...
Page 180: ...Chapter 10 Quality of Service QoS VMG5313 B10A B30A Series User s Guide 180 ...
Page 198: ...Chapter 11 Network Address Translation NAT VMG5313 B10A B30A Series User s Guide 198 ...
Page 210: ...Chapter 14 Interface Group VMG5313 B10A B30A Series User s Guide 210 ...
Page 218: ...Chapter 15 USB Service VMG5313 B10A B30A Series User s Guide 218 ...
Page 232: ...Chapter 17 Firewall VMG5313 B10A B30A Series User s Guide 232 ...
Page 240: ...Chapter 19 Parental Control VMG5313 B10A B30A Series User s Guide 240 ...
Page 250: ...Chapter 21 Certificates VMG5313 B10A B30A Series User s Guide 250 ...
Page 296: ...Chapter 23 Voice VMG5313 B10A B30A Series User s Guide 296 ...
Page 300: ...Chapter 24 Log VMG5313 B10A B30A Series User s Guide 300 ...
Page 308: ...Chapter 27 xDSL Statistics VMG5313 B10A B30A Series User s Guide 308 ...
Page 318: ...Chapter 30 Remote Management VMG5313 B10A B30A Series User s Guide 318 ...
Page 322: ...Chapter 32 TR 064 VMG5313 B10A B30A Series User s Guide 322 ...
Page 332: ...Chapter 36 Log Setting VMG5313 B10A B30A Series User s Guide 332 ...
Page 336: ...Chapter 37 Firmware Upgrade VMG5313 B10A B30A Series User s Guide 336 ...
Page 352: ...Chapter 40 Troubleshooting VMG5313 B10A B30A Series User s Guide 352 ...
Page 354: ...354 ...
Page 374: ...Appendix B Wireless LANs VMG5313 B10A B30A Series User s Guide 374 ...
Page 390: ...Appendix E Legal Information VMG5313 B10A B30A Series User s Guide 390 ...