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Appendix E Wireless LANs
P-2812HNU-51c User’s Guide
392
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 229
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.
Содержание P-2812HNU-51c
Страница 2: ......
Страница 8: ...Safety Warnings P 2812HNU 51c User s Guide 8 ...
Страница 10: ...Contents Overview P 2812HNU 51c User s Guide 10 ...
Страница 19: ...19 PART I User s Guide ...
Страница 20: ...20 ...
Страница 73: ...73 PART II Technical Reference ...
Страница 74: ...74 ...
Страница 88: ...Chapter 4 Status Screens P 2812HNU 51c User s Guide 88 ...
Страница 118: ...Chapter 5 WAN Setup P 2812HNU 51c User s Guide 118 ...
Страница 204: ...Chapter 9 Voice P 2812HNU 51c User s Guide 204 ...
Страница 210: ...Chapter 10 File Sharing P 2812HNU 51c User s Guide 210 ...
Страница 216: ...Chapter 11 Firewall P 2812HNU 51c User s Guide 216 ...
Страница 223: ...Chapter 12 Certificate P 2812HNU 51c User s Guide 223 Figure 99 Certificate Details ...
Страница 232: ...Chapter 13 Static Route P 2812HNU 51c User s Guide 232 ...
Страница 236: ...Chapter 14 Policy Forwarding P 2812HNU 51c User s Guide 236 ...
Страница 252: ...Chapter 16 Quality of Service QoS P 2812HNU 51c User s Guide 252 ...
Страница 274: ...Chapter 19 Universal Plug and Play UPnP P 2812HNU 51c User s Guide 274 ...
Страница 284: ...Chapter 21 Interface Group P 2812HNU 51c User s Guide 284 ...
Страница 288: ...Chapter 22 System Settings P 2812HNU 51c User s Guide 288 ...
Страница 292: ...Chapter 23 Logs P 2812HNU 51c User s Guide 292 ...
Страница 300: ...Chapter 24 Tools P 2812HNU 51c User s Guide 300 ...
Страница 320: ...Chapter 27 Product Specifications P 2812HNU 51c User s Guide 320 ...
Страница 336: ...Appendix A Network Troubleshooting P 2812HNU 51c User s Guide 336 ...
Страница 376: ...Appendix C Pop up Windows JavaScripts and Java Permissions P 2812HNU 51c User s Guide 376 ...
Страница 388: ...Appendix D IP Addresses and Subnetting P 2812HNU 51c User s Guide 388 ...