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, atleast 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 trottled down.)
  • dev.ath.0.tpack: controll the ack power seperatly (normally the same as tpcts)
  • dev.ath.0.tpcts: controll the cts power seperatly (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     -               -