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TCP

Transmission Control Protocol. A communications protocol that breaks down messages into packets (datagrams) to transmit. Ensures all information arrives and in the right order.

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TELEC

See MIC.

 


 

Temporal Isolation: Time Division Multiplexing

Time Division Multiplexing (TDM) is a coexistence method where the co-located devices take turns transmitting. The devices are linked together with input/output signaling pins or "wires". An output wire is asserted by a radio when transmitting; this indicates to the other device on the corresponding input wire that it should refrain from transmitting during this time.

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ThirdPartyConfig

If the ThirdPartyConfig profile is selected as the active profile, then SCU works in tandem with WZC or other third-party applications (such as Juniper Networks Odyssey Access Client) for configuration of all radio and security settings for the radio. The third-party application must be used to define the SSID, Auth Type, EAP Type, and Encryption settings. SCU can be used to define the Client Name, Power Save, Tx Power, Bit Rate, and Radio Mode settings. Those SCU profile settings and the third-party application settings are applied to the radio when ThirdPartyConfig is selected as the active profile and a power cycle is performed.

On some devices that run Pocket PC or Windows Mobile, the radio will not associate if WPA with pre-shared keys (WPA-PSK) is used with WZC. To use WPA-PSK with your device, you must use an SCU profile other than ThirdPartyConfig.

 


 

Throughput

Throughput is a measurement of the speed at which information is sent, expressed in bits per second (bps). Unlike data rate (which applies to everything that is sent, both overhead [headers] and data), throughput applies to just the data that is sent. Because of this, throughput is a better measurement of the actual user experience.

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TKIP

TKIP (Temporal Key Integrity Protocol) is the encryption method defined with WPA. Like WEP, TKIP uses RC4 encryption, but TKIP is designed to address vulnerabilities of WEP by providing these enhancements:

  • Longer initialization vector, which minimizes the chance that a key will be reused during a session.
  • Key hashing, which results in a different key for each data packet.
  • Message integrity check (MIC), which ensures that the message is not altered in transit between sender and receiver.

Because it relies on RC4, TKIP encryption is not as strong as AES-CCMP encryption.

 


 

Toolchain

Also known as an Integrated Development Environment, a toolchain is the collection of utilities that are used to create a software product. Oftentimes the output of one utility becomes the input of the next. In this way, they form a throughput chain. A toolchain can also be thought of as similar to an assembly line, where each utility in the chain performs its required function.

 


 

Transceiver

Shortened form of transmitter-receiver. A device that receives and transmits analog or digital signals.

 


 

Transmit API

A command that allows the OEM Host to send data to a single or multiple (broadcast) transceiver on a packet-by-packet basis.

 


 

Transmit Power Control

Transmit Power Control (TPC) is an element of the IEEE 802.11h mechanism used to address interference issues between wireless networks. It governs the operation of Wi-Fi in the 5 GHz frequency band. 802.11h was defined because the sharing of the 5 GHz band in Europe varied from country to country, and there were concerns that the use of Wi-Fi devices and networks at certain frequencies would carse interference with devices such as satellite services and military radars. With TPC, a Wi-Fi radio automatically reduces its transmission output power when other networks are within range. Reduced power results in reduced interference and, as an additional benefit, increases battery capacity. The power level of a single device can be reduced by 6 dB which should result in an ccumulated power level reduction - the sum of radiated power of all devices currently transmitting - of at least 3 dB, which is half the power

 


 

Tray Icon (SCU Global Setting)

Tray Icon is an SCU Global setting that allows you to enable or disable the System Tray icon.

The tray icon provides a visual status for the device's Summit radio and it enables the user to launch SCU. This service is available only for Windows CE and Windows Mobile.

The software for the service is installed with other Summit software in a .cab file. The service is active only when all of the following are true:

  • A Summit radio is installed in the device or inserted in an external slot in the device.
  • The device is active
  • Windows Zero Config is not active.
  • The SCU Tray Icon global setting is On

When the service is active, it queries the driver every three seconds for the status of the connection for the active profile and displays one of the following icons:

 

The radio is not associated/authenticated to an access point.

 

The signal strength (RSSI) for the current access point (to which the radio is associated) is -90 dBm or weaker, which means that a Summit 802.11b/g radio will operate at 802.11b data rates only.

 

The RSSI for the current access point is stronger than -90 dBm but not stronger than -70 dBm, which means that a Summit radio will operate at 802.11g or 802.11a data rates that are less than 54 Mbps.

 

The RSSI for the current access point is stronger than -70 dBm but not stronger than -50 dBm, which means that a Summit radio should operate consistently at 54 Mbps.

 

The RSSI for the current access point is stronger than -50 dBm.

Tapping the icon launches the SCU. On most CE devices, the System Tray icon is not visible while SCU is running, although the service remains active.

Note: If SCU usually runs on the device, or if you want to maximize performance, then you should disable the System Tray icon service by setting the Tray Icon global setting to Off and power cycling the device. 

 


 

TTLS Inner Method (SCU Global Setting)

TTLS Inner Method is an SCU Global setting that indicates the authentication method that is used within the secure tunnel created by EAP-TTLS. Inner authentication methods include:

The SCU TTLS Inner Method default setting is Auto-EAP.

 


 

Two-Wire/Three-Wire Coexistence

In two-wire schemes, two signaling pins are used to arbitrate between the Bluetooth and Wi-Fi radios.

  • WLAN_ACTIVE - An output pin on the Wi-Fi radio that, when asserted, signals to the Bluetooth radio when the 802.11 radio is transmitting.
    • The WLAN radio holds high the WLAN_ACTIVE pin when transmitting and indicates that the Bluetooth radio should not transmit.
     
  • BT_ACTIVE - An output pin on the Bluetooth radio that, when asserted, signals to the Wi-Fi radio when the Bluetooth radio is transmitting.
    • The Bluetooth radio holds high the BT_ACTIVE pin when transmitting and indicates that the WLAN radio should not transmit.
     

The three-wire Bluetooth Coexistence scheme adds a third wire (BT_PRIORITY) to the two-wire scheme for an additional signal:

  • WLAN_ACTIVE - An output pin on the Wi-Fi radio that, when asserted, signals to the Bluetooth radio when the 802.11 radio is transmitting.
    • The WLAN radio holds high the WLAN_ACTIVE pin when transmitting and indicates that the Bluetooth radio should not transmit.
     
  • BT_ACTIVE - An output pin on the Bluetooth radio that, when asserted, signals to the Wi-Fi radio when the Bluetooth radio is transmitting.
    • The Bluetooth radio holds high the BT_ACTIVE pin when transmitting and indicates that the WLAN radio should not transmit.
     
  • BT_PRIORITY - An output pin on the Bluetooth radio that, when asserted, signals to the Wi-Fi radio when the Bluetooth radio is transmitting latency-sensitive (high priority) packets such as SCO voice packets.
    • The Bluetooth radio holds high the BT_PRIORITY pin when transmitting and indicates that the WLAN radio should not transmit or should discontinue transmitting if in the process of transmitting.
     

Note: A wireless LAN radio with a two-wire coexistence scheme does not have a BT_PRIORITY input pin and therefore cannot prioritize between low and high priority Bluetooth packets. Because of this, it treats BT_ACTIVE and BT_PRIORITY exactly the same; there is no possibility of prioritization. Implementers may tie the BT_ACTIVE and BT_PRIORITY outputs to a single BT_ACTIVE input on the Wi-Fi radio using an OR switch.

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Tx Diversity

Transmit diversity refers to the use of multiple antennas to increase the odds that a functional signal is received. Data is transmitted differently across two antennas and the receiving device must be aware of the setup to properly decode data. This technique is used to reduce signal fade.

Related Topics: 

Tx Diversity (SCU Global Setting)
 

 


 

Tx Diversity (SCU Global Setting)

Tx (Transmit) Diversity is an SCU Global setting that indicates how to handle antenna diversity when transmitting data to an access point. Tx Diversity setting options include:

  • Main only - Indicates use of the main antenna only.
  • Aux only - Indicates use of the auxiliary antenna only.
  • On - Indicates the use of diversity (both antennas).

 


 

Tx Power

In a Wi-Fi radio, the Tx Power (transmission power) setting controls the power in milliwatts that may be used to operate the antenna. This value is subject to regional regulations. Additionally, increasing the Tx Power beyond an acceptable range may create transmission problems for surrounding access points and client devices. Tx Power may be configured in the SCU.

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Tx Power (SCU Status window)

In SCU, Tx Power displays on the Status window to indicate the power of the radio, in milliwatts (mW). This value can be overwritten by the AP; the AP can dictate to the client what power to use.

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