Appendix D Wireless LANs
VSG1432-B101 Series User’s Guide
368
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 198
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 VSG1432-B101 - V1.10
Page 2: ......
Page 8: ...Safety Warnings VSG1432 B101 Series User s Guide 8 ...
Page 10: ...Contents Overview VSG1432 B101 Series User s Guide 10 ...
Page 20: ...Table of Contents VSG1432 B101 Series User s Guide 20 ...
Page 21: ...21 PART I User s Guide ...
Page 22: ...22 ...
Page 40: ...Chapter 2 The Web Configurator VSG1432 B101 Series User s Guide 40 ...
Page 67: ...67 PART II Technical Reference ...
Page 68: ...68 ...
Page 74: ...Chapter 5 Network Map and Status Screens VSG1432 B101 Series User s Guide 74 ...
Page 146: ...Chapter 8 Home Networking VSG1432 B101 Series User s Guide 146 ...
Page 150: ...Chapter 9 Static Routing VSG1432 B101 Series User s Guide 150 ...
Page 174: ...Chapter 11 Policy Forwarding VSG1432 B101 Series User s Guide 174 ...
Page 192: ...Chapter 12 Network Address Translation NAT VSG1432 B101 Series User s Guide 192 ...
Page 198: ...Chapter 13 Dynamic DNS Setup VSG1432 B101 Series User s Guide 198 ...
Page 224: ...Chapter 16 Firewall VSG1432 B101 Series User s Guide 224 ...
Page 230: ...Chapter 18 Parental Control VSG1432 B101 Series User s Guide 230 ...
Page 278: ...Chapter 25 Traffic Status VSG1432 B101 Series User s Guide 278 ...
Page 282: ...Chapter 26 IGMP Status VSG1432 B101 Series User s Guide 282 ...
Page 290: ...Chapter 28 Remote Management VSG1432 B101 Series User s Guide 290 ...
Page 294: ...Chapter 29 Time Settings VSG1432 B101 Series User s Guide 294 ...
Page 298: ...Chapter 30 Logs Setting VSG1432 B101 Series User s Guide 298 ...
Page 314: ...Chapter 34 Troubleshooting VSG1432 B101 Series User s Guide 314 ...
Page 344: ...Appendix A Setting up Your Computer s IP Address VSG1432 B101 Series User s Guide 344 ...
Page 354: ...Appendix B IP Addresses and Subnetting VSG1432 B101 Series User s Guide 354 ...
Page 380: ...Appendix D Wireless LANs VSG1432 B101 Series User s Guide 380 ...