Changes between Version 27 and Version 28 of 802.11/MAC/Lower/Retransmissions
- Timestamp:
- May 6, 2015, 10:52:08 AM (9 years ago)
Legend:
- Unmodified
- Added
- Removed
- Modified
-
802.11/MAC/Lower/Retransmissions
v27 v28 196 196 197 197 In this example, we see the error introduced in [#ExampleL.3 Example L.3] taken to its limit when the maximum retransmission limit is reached. Since RTS transmissions count as "short" frames, this example is actually equivalent to [#ExampleS.3 Example S.3]. 198 199 == Example L.6 == 200 201 {{{ 202 #!div style="overflow-x:scroll; border:1pt solid" 203 [[Image(ex_l_6.png)]] 204 }}} 205 206 This example mixes the long and short failures introduced respectively in [#ExampleL.2 Example L.2] and [#ExampleL.3 Example L.3], respectively. In this example, an RTS transmission fails 6 times. On the 7th attempt, however, a CTS is received. According to '''''Excerpt F from 9.3.3 of 802.11-2012''''' from [#ExampleL.3 Example L.3], the SSRC is reset to 0 at this time. Neither that SRC nor the CW are reset at this time. The successful reception of the CTS then causes then MPDU to be transmitted. Failure to receive an ACK for this MPDU causes the LRC and SLRC to increment. The CW would have also increased had it not already been at its maximum value. From this point forward, the behavior of the example matches [#ExampleL.2 Example L.2]. 207 208 Notice that having a ''dot11ShortRetryLimit'' of 7 and a ''dot11LongRetryLimit'' of 4 actually allows for a total of 10 "attempts" to transmit (6 RTS-only transmissions followed by 4 RTS and MPDU transmissions).