| 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]. 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). |
| | 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. This point in particular is often misunderstood. The reset of an SSRC to 0 due to the successful reception of a CTS does not coincide with the reset of the SRC. '''''Excerpt A of Section 9.3.4.4 of 802.11-2012''''' from [#ExampleS.1 Example S.1] does not apply here. That excerpt very specifically applies to "a frame that requires acknowledgment." This is not true for the RTS that was just successful. |
| | 207 | |
| | 208 | 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]. 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). |
