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| Field | Description |
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| DTIM Period | All Beacon frames include a Traffic Information Map information element (TIM |
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| IE). In some beacon frames, the TIM IE includes a Delivery Traffic Information |
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| Map (DTIM) message. These special DTIM beacons are sent at an interval |
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| specified in the DTIM period. Another way of expressing this is: |
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| Every xth TIM IE is DTIM (where X= DTIM Period) |
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| The DTIM beacon alerts the clients that multicast and broadcast packets |
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| buffered at the AP will be transmitted immediately after the transmission of this |
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| beacon frame. |
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| To set the DTIM Period for an AP, specify a DTIM period within the given range |
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| (1 - 255). |
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| The higher the DTIM period, the longer the delay between the delivery of |
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| multicast frames. |
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| The DTIM period, measured in beacon intervals, indicates the number of |
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| beacons between two consecutive DTIM beacons. For example, if you set this |
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| to "1" clients will check for buffered data on the AP at every beacon. If you set |
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| this to "2", clients will check on every other beacon. If you set this to 10, clients |
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| will check on every 10th beacon. |
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| Fragmentation | Specify a number between 256 and 2,346 to set the frame size threshold in |
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| Threshold | bytes. |
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| The fragmentation threshold is a way of limiting the size of packets (frames) |
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| transmitted over the network. If a packet exceeds the fragmentation threshold |
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| set here, the fragmentation function will be activated and the packet will be sent |
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| as multiple 802.11 frames. |
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| If the packet being transmitted is equal to or less than the threshold, |
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| fragmentation will not be used. |
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| Setting the threshold to the largest value (2,346 bytes) effectively disables |
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| fragmentation. |
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| Fragmentation involves more overhead both because of the extra work of |
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| dividing up and reassembling of frames it requires, and because it increases |
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| message traffic on the network. However, fragmentation can help improve |
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| network performance and reliability if properly configured. |
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| Sending smaller frames (by using lower fragmentation threshold) may help with |
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| some interference problems; for example, with microwave ovens. |
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| By default, fragmentation threshold is 2346. We recommend not using |
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| fragmentation unless you suspect radio interference. The additional headers |
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| applied to each fragment increase the overhead on the network and can greatly |
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| reduce throughput. |
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