Wireless Interface Configuration Details¶
Wireless Card Options¶
These options are common between all SSIDs/VAPs on the same wireless card.
Persist common settings: Enabling this preserves the common wireless configuration through interface deletions and reassignments.
Standard: The wireless standard to use for clients, such as 802.11g or 802.11b. Only the options supported by the installed card are displayed.
802.11g OFDM Protection Mode: For IEEE 802.11g, use the specified technique for protecting OFDM frames in a mixed 11b/11g network. May be left off is the network is not mixed.
Transmit power: Controls the output (transmit) power of the card. Typically only a few discreet power settings are available and the driver will use the setting closest to the specified value. Not all adapters support changing the transmit power setting, and it may be limited by local regulations.
Channel: A list of channels supported by the installed wireless adapter, displayed in the following format:
wireless standards - channel # (frequency @ max TX power / TX power allowed in reg. domain)
When running an access point, it is best to explicitly set a channel. Do not leave this on Auto!
Antenna settings:
Diversity: Switch off and on the use of antenna diversity (normally only used if two antennas are connected), to allow both antenna to be used for both transmit and receive.
Transmit/Receive Antenna: Allows manually specifying which antenna should be used to transmit and which is used to receive. The numbers may not line up with the numbers noted on the physical adapter.
Distance setting: This field can be used to tune ACK/CTS timers to fit the distance between AP and Client. It is measured in Meters and works only for Atheros based cards.
Regulatory settings: Specifies the locality in which the card is used, so that the card will comply with local laws and regulations for radio signals. Use of some channels and behaviors (such as the use of 802.11n) require an appropriate Regulatory Domain to be configured.
Regulatory domain: The governing body that controls transmission regulations in the region where the firewall is deployed, such as the FCC or ETSI.
Country: The country code and regulatory domain in which the card is used. Any country setting other than “Default” will override the regulatory domain setting.
Location: The physical location of the device, typically Indoor. Some regulatory bodies have different rules for Indoor vs Outdoor use.
Wireless Access Point (hostap) with WPA2¶
Configuration of the wireless Interface:
Channel: Be sure to explicitly set a desired channel in the top section when running an access point
Mode: Access Point
SSID: Whatever desired, typically something short without spaces in the name.
Enable WPA: Checked
WPA Pre-Shared Key: The “password” to use for wireless access by clients (8-63 chars)
WPA mode: WPA2
WPA Key Management Mode: Pre Shared Key
Authentication: Open System Authentication
WPA Pairwise: AES (Recommended)
Other interesting options:
Minimum wireless standard: Set this to prevent older/slower clients from connecting and reducing the speed of the network.
Allow intra-BSS communication: Check this to allow wireless clients to contact each other
Enable WME: Setting this option will force the card to use WME (wireless QoS). Can help especially with higher speeds such as 802.11n.
Enable Hide SSID: Stops the firewall from transmitting/advertising/broadcasting the SSID to the public. Clients must be manually configured to use the SSID in these cases.
WEP: Older/broken encryption. Only use if someone forces it. All modern clients support better options such as WPA2.
Key Rotation: How often to regenerate client keys. May need to be raised to avoid frequently client interruptions on higher speed networks.
Master Key Regeneration: Controls how often the master key is regenerated. Should not be shorter than the Key Rotation time. Defaults to 3600 (1 hour).
Strict Key Regeneration: Forces the AP to generate new keys when a client disassociates, to protect the security of clients that are still connected.
Wireless client with AES encryption¶
Config on the wireless page:
Set Mode: Infrastructure Set SSID: SSID of AP Enable WPA: Checked Set The PSK: Shared key from AP in ascii Set WPA mode: WPA Set wpa Key Management Mode: Pre Shared Key Set Authentication: Open System Authentication Set WPA Pairwise: AES
Channel: Use Auto or configure this to match the channel of the AP to which this client will connect.
Mode: Infrastructure (BSS)
SSID: The SSID of the AP to which this client will connect.
The following settings must match those found on the AP, but examples are provided:
Enable WPA: Checked
WPA Pre-Shared Key: The “password” set on the AP
WPA mode: WPA2
WPA Key Management Mode: Pre Shared Key
Authentication: Open System Authentication
WPA Pairwise: AES (Recommended)
That should be it, Good luck and have fun.
Tips To get card capabilities and more¶
list available channels:
ifconfig "IF-NAME" list chan
lists modes:
ifconfig -m "IF-NAME"
view settings:
ifconfig -v "IF-NAME"
list stations:
ifconfig "IF-NAME" list sta
see available APs (Also shown on Diagnostics > Wireless):
ifconfig "IF-NAME" list scan
list wireless QoS settings:
ifconfig "IF-NAME" list wme
Interesting sysctls from shell that can not be controlled from GUI¶
dev.ath.0.tpscale: 0,1,2,3,4 (size of increment that TPC will use to up/down the power, normally 1 is the best choice, at least that is my experience)
dev.ath.0.tpc: 0,1 (0=disable 1=enable)
dev.ath.0.tpack: 0 -> 99 (ack power)
dev.ath.0.tpcts: 0 -> 99 (cts power)
A little more description:
dev.ath.0.tpc: Switch on or off Transmission Power Control (can be tricky in point to multipoint applications)
dev.ath.0.tpscale: Size of the increment that TPC will use to up/down the power, normally 1 is the best choice, atleast that is my experience. A higher scale value will most likely make the link drop if the signal is close to what it needs to be and the TPC is throttled down.)
dev.ath.0.tpack: control the ack power separately (normally the same as tpcts)
dev.ath.0.tpcts: control the cts power separately (normally the same as tpack)
Tuning ACK timers manually:
Real life values:
range ack-timeout
5GHz 5GHz-turbo 2.4GHz-G
0km default default default
5km 52 30 62
10km 85 48 96
15km 121 67 133
20km 160 89 174
25km 203 111 219
30km 249 137 268
35km 298 168 320
40km 350 190 375
45km 405 - -