Wi-Fi Direct
Wi-Fi Direct is a wireless standard that allows devices to connect with each other without requiring a wireless access point. Wi-Fi Direct negotiates the link with a Wi-Fi Protected Setup (WPS) system that assigns each device a limited wireless access point.
Establishing a peer-to-peer (P2P) link has the following phases:
-
P2P discovery, which allows to search for P2P devices in the vicinity
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P2P group formation, a P2P group is formed with the identification of one of the devices as group owner. A device can either become group owner (GO) autonomously if configured to do so or it can be negotiated between devices with the exchange of GO intents.
-
P2P provisioning, which authenticates the link by using either Push Button Configuration (PBC) or PIN authentication.
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P2P connection, when the connection between a Group Owner (GO) and a Group Client (GC) is actually established.
The QCA6574 driver on load creates a p2p0 interface that is used by the wpa supplicant for P2P group formation. Once a group is formed, virtual {wifi-p2p-interface}N interfaces are created, where N is an index starting at 0. These virtual interfaces are then used for provisioning.
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Group additions, find and connect operations happen on the p2p0 interface.
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Provisioning occurs on the virtual {wifi-p2p-interface}N interfaces.
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This configuration requires MAC addresses to be different and unique. Configure the virtual interfaces before attempting to connect more than one device.
By default, Digi Embedded Yocto configures the Wi-Fi Direct functionality by adding a p2p0 interface in /etc/network/interfaces. The interface is not automatically brought up.
The following instructions show how to configure the device to use Wi-Fi Direct.
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Delete the wlan1 interface to make sure we can assign a virtual MAC address to the interface {wifi-p2p-interface}0 that will be created. To delete the wlan1 interface, use the following command:
~# iw dev wlan1 del
-
Bring up the p2p0 interface:
~# ifup p2p0
The following examples will use two ConnectCore 6UL devices to establish P2P connections. For more information about the wpa-supplicant P2P specific commands, see the wpa_supplicant and Wi-Fi P2P README.
Autonomous GO creation
| In kernel v4.9, peer-to-peer Autonomous Group Owner (Autonomous GO) configuration fails due to an incompatibility in the wireless driver. Digi recommends you use the Negotiated Group Owner (Negotiated GO) method. |
Create Autonomous Group Owner (GO) and join using PBC method
Peer (GO) ---- PBC --- Peer (GC)
| Steps | Peer CC6UL1 | Peer CC6UL2 |
|---|---|---|
1 |
wpa_cli -ip2p0 |
wpa_cli -ip2p0 |
2 |
p2p_group_add |
|
3 |
|
p2p_find |
4 |
|
p2p_connect <CC6UL1_go_mac_addr> pbc join |
5 |
Ctrl-c to exit |
Ctrl-c to exit |
6 |
wpa_cli -i {wifi-p2p-interface}0 wps_pbc |
|
7 |
ifconfig {wifi-p2p-interface}0 <CC6UL1_ip_addr> |
ifconfig {wifi-p2p-interface}0 <CC6UL2_ip_addr> |
8 |
ping <CC6UL2_ip_addr> |
ping <CC6UL1_ip_addr> |
Create Autonomous GO and join using PIN from GO
Peer (GO) ---- PIN --- Peer (GC)
| Steps | Peer CC6UL1 | Peer CC6UL2 |
|---|---|---|
1 |
wpa_cli -ip2p0 |
wpa_cli -ip2p0 |
2 |
p2p_group_add |
|
3 |
|
p2p_find |
4 |
Ctrl-c to exit |
|
5 |
wpa_cli -i{wifi-p2p-interface}0 wps_pin any (shows <pin>) |
|
6 |
|
p2p_connect <CC6UL1_go_mac_addr> <pin> join |
7 |
|
Ctrl-c to exit |
8 |
ifconfig {wifi-p2p-interface}0 <CC6UL1_ip_addr> |
ifconfig {wifi-p2p-interface}0 <CC6UL2_ip_addr> |
9 |
ping <CC6UL2_ip_addr> |
ping <CC6UL1_ip_addr> |
Create Autonomous GO and join using PIN from GC
Peer (GO) ---- PIN --- Peer (GC)
| Steps | Peer CC6UL1 | Peer CC6UL2 |
|---|---|---|
1 |
wpa_cli -ip2p0 |
wpa_cli -ip2p0 |
2 |
p2p_group_add |
|
3 |
|
p2p_find |
4 |
|
p2p_connect <CC6UL1_go_mac_addr> pin join (shows <pin>) |
5 |
Ctrl-c to exit |
Ctrl-c to exit |
6 |
wpa_cli -i{wifi-p2p-interface}0 wps_pin any <pin> |
|
7 |
ifconfig {wifi-p2p-interface}0 <CC6UL1_ip_addr> |
ifconfig {wifi-p2p-interface}0 <CC6UL2_ip_addr> |
8 |
ping <CC6UL2_ip_addr> |
ping <CC6UL1_ip_addr> |
Create Autonomous GO and invite GC using PBC
Peer (GO) ---- PBC --- Peer (GC)
| Steps | Peer CC6UL1 | Peer CC6UL2 |
|---|---|---|
1 |
wpa_cli -ip2p0 |
wpa_cli -ip2p0 |
2 |
p2p_group_add |
|
3 |
|
p2p_find |
4 |
p2p_invite group={wifi-p2p-interface}0 peer=<CC6UL2_mac_addr> |
|
5 |
|
p2p_connect <CC6UL1_go_mac_addr> pbc join |
6 |
Ctrl-c to exit |
Ctrl-c to exit |
7 |
wpa_cli -i {wifi-p2p-interface}0 wps_pbc |
|
8 |
ifconfig {wifi-p2p-interface}0 <CC6UL1_ip_addr> |
ifconfig {wifi-p2p-interface}0 <CC6UL2_ip_addr> |
9 |
ping <CC6UL2_ip_addr> |
ping <CC6UL1_ip_addr> |
| For any of these methods, if you want to use the 5GHz frequency, issue p2p_group_add freq=5180 in step two. |
Negotiated GO
Negotiate GO and join using PIN
Peer (GO | GC) ---- PIN --- Peer (GO | GC)
| Steps | Peer CC6UL1 | Peer CC6UL2 |
|---|---|---|
1 |
wpa_cli -ip2p0 |
wpa_cli -ip2p0 |
2 |
p2p_find |
|
3 |
|
p2p_find |
4 |
p2p_connect <CC6UL2_go_mac_addr> pin go_intent=1 |
|
5 |
|
p2p_connect <CC6UL1_go_mac_addr> <pin> go_intent=15 |
6 |
Ctrl-c to exit |
Ctrl-c to exit |
7 |
ifconfig {wifi-p2p-interface}0 <CC6UL1_ip_addr> |
ifconfig {wifi-p2p-interface}0 <CC6UL2_ip_addr> |
8 |
ping <CC6UL2_ip_addr> |
ping <CC6UL1_ip_addr> |
Negotiate GO and join using PBC
Peer (GO | GC) ---- PBC --- Peer (GO | GC)
| Steps | Peer CC6UL1 | Peer CC6UL2 |
|---|---|---|
1 |
wpa_cli -ip2p0 |
wpa_cli -ip2p0 |
2 |
p2p_find |
|
3 |
|
p2p_find |
4 |
p2p_connect <CC6UL2_go_mac_addr> pbc go_intent=1 |
|
5 |
|
p2p_connect <CC6UL1_go_mac_addr> pbc go_intent=14 |
6 |
Ctrl-c to exit |
Ctrl-c to exit |
7 |
ifconfig {wifi-p2p-interface}0 <CC6UL1_ip_addr> |
ifconfig {wifi-p2p-interface}0 <CC6UL2_ip_addr> |
8 |
ping <CC6UL2_ip_addr> |
ping <CC6UL1_ip_addr> |
