How to drop specific packet captured in NS-3 mesh node?

[Caio Marcos Chaves Viana]

Hi, I'm using NS-3 v3.37 to simulate a WiFi Mesh network.

The grid topology (actually only one line, with IEEE 802.11s stack installed at each node, HWMP protocol) contains 3 WiFi Mesh nodes, Node0, Node1 and Node2. Then I bind a UDP socket (acting as receiver) in Node2, and another (acting as sender) in Node0. Node0 send a UDP packet to Node2 through Node1.

The topology as follow:

Node0 (sender) ---> Node1 ----> Node2 (receiver)

Then I set a MonitorSnifferRx function on Node1 to listen udp packets sent from Node0 to Node2 using Config::ConnectWithoutContext:

Config::ConnectWithoutContext ("/NodeList/1/DeviceList/*/Phy/MonitorSnifferRx", MakeCallback (&SniffRxPkt));

In Node1 callback function "SniffRxPkt", I want to drop the packet received from Node0 based on an arbitrary condition (e.g. the time that packet was received).

My question is : When a specific UDP packet captured in Node1's MonitorSnifferRx callback function, how can I drop it thus it will not transfer to Node2?

Thanks and Regards,

Caio.

[Tommaso Pecorella]

Hi,

you can't do that (in the MonitorSnifferRx function) because that function uses a copy of the packet. To drop the packet you'll have to modify the HWMP code to add a drop condition. Or you can modify the channel to add a selective packet drop, but that's quite more complex.