Changes between Version 6 and Version 7 of HowTo/virtualMobility


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Timestamp:
Sep 6, 2006, 4:19:25 PM (18 years ago)
Author:
cmdavies
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  • HowTo/virtualMobility

    v6 v7  
    77
    88The method described here is a third way. It is implemented as a modification to the madwifi driver. Basically what it does is allows incoming packets to be filtered by sending MAC address. These filtered packets can have an arbitrary RSSI assigned to them and an arbitrary percent of these incoming packets can be ignored in order to simulate a poor radio environment.
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     10Since this modification is at a very low layer in the madwifi driver, it is completely transparent to all routing and packet shifting performed by both the kernel and userspace applications.
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     12It is important to remember that when using this tool packets are still send and received at the hardware layer, and thus you will still need to be sure you're not saturating your radio environment even if you're nodes don't seem to be receiving packets.
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    1016== Using the Filter ==
     
    5359}}}
    5460
    55 Then for each radio, you'll simply specify which senders you'd like to hear from. For example, if you want to allow ath0 on nodes 3-4 and 3-6 to hear each other you'd enter these commands (where the MAC address is the MAC address of the radio on the node you want to hear from)
     61Then for each radio, you'll simply specify which senders you'd like to hear from. For example, if you want to allow ath0 on nodes 3-4 and 3-6 to hear each other you'd enter these commands (where the MAC address is the MAC address of the radio on the node you want to hear from):
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     63{{{
     64node3-4:~# iwpriv ath0 orbitfilter 0x00 0xbf 0xcd 0x6D 0x24 0x18 100 0xFF
     65}}}
     66{{{
     67node3-4:~# iwpriv ath0 orbitfilter 0x00 0x56 0xcd 0x12 0xc4 0x8d 100 0xFF
     68}}}
     69
     70Using 0xFF for the RSSI value leaves the RSSI value unchanged from what the hardware layer reported.
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