Using the 802.11 Reference Design: IBSS Application


The IBSS uses ETH A as its source and sink for all wireless data packets. Note: ETH A defaults to using a 1Gbps speed. It will not auto-negotiate to 100 Mbps when connected to a slower Ethernet port. The IBSS code assumes a single Ethernet device is connected to ETH A, such as a PC or network camera. The IBSS code bridges the wired and wireless interfaces, translating between the wired device's MAC address and the WARP node's wireless MAC address. This translation will not work if multiple Ethernet devices are connected to the IBSS node's ETH A interface via a switch.

The IBSS uses ETH B for interaction with the experiments framework.

User IO

Hex Displays: the IBSS application uses the hex displays to show the number of peer nodes it currently observes in its IBSS. Nodes can join leave an IBSS at any time, potentially without the knowledge of every other peer in the network. Each IBSS node keeps a list of all the nodes from whom it has received beacon frames or to whom it has attempted transmissions, either of which indicates potential IBSS membership. The hex display shows the length of this list. If the BSS is Null, then "--" will be displayed.

DIP Switch: the IBSS uses the left-most switch to enable or disable active scan and creation of a BSS on boot. When the left switch is up the IBSS will not search for or create a new BSS on boot. The node can still be added to a BSS via wlan_exp commands.


Refer to the UART usage page for an overview of how the 802.11 design uses the UART cores on each CPU.

The normal UART output on boot of the AP application is:

----- Mango 802.11 Reference Design -----
----- v1.0 ------------------------------
----- wlan_mac_ibss ----------------------

< High Framework Boot Messages - See Above >

WLAN MAC IBSS boot complete:
  MAC Addr     : 40-D8-55-04-21-4A

Press the Esc key in your terminal to access the UART menu

After a short while the IBSS application will then print:

Unable to find 'WARP-IBSS' IBSS. Creating new network.
IBSS Details:
  BSSID           : 42-D8-55-04-21-4A
   SSID           : WARP-IBSS
   Channel        : 1
   Beacon Interval: 100 TU (102400 us)

This is the normal behavior, indicating the IBSS did not find any existing IBSS network using the SSID "WARP-IBSS", so it creates one and starts sending beacons.

The IBSS application implements a simple UART menu, accessed by hitting ESC key:

********************** Station Menu **********************
[1] - Interactive Station Status
[2] - Print Queue Status
[3] - Print all Observed Statistics

[a] -   display BSS information
[r/R] - change unicast rate

Option 1 will show a sub-menu with a command to reset all Tx/Rx statistics.

Option 2 will print the queue status and occupancy

Option 3 will print the Tx/Rx statistics for all traffic at the IBSS node.

Option a will print the list of wireless networks the IBSS has discovered during its active scan.

Last modified 8 years ago Last modified on Mar 22, 2016, 5:27:24 PM