Appendix A
A.1 Glossary of Terms
SCALANCE W1750D CLI
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Function Manual, 03/2019, C79000-G8976-C452-04
TLV
Type-length-value or Tag-Length-Value. TLV is an encoding format. It refers
to the type of data being processed, the length of the value, and the value for
the type of data being processed.
ToS
Type of Service. The ToS field is part of the IPv4 header, which specifies
datagrams priority and requests a route for low-delay, high-throughput, or a
highly reliable service.
TPC
Transmit Power Control. TPC is a part of the 802.11h amendment. It is used
to regulate the power levels used by 802.11a radio cards.
TPM
Trusted Platform Module. TPM is an international standard for a secure cryp-
toprocessor, which is a dedicated microcontroller designed to secure hard-
ware by integrating cryptographic keys into devices.
TSF
Timing Synchronization Function. TSF is a WLAN function that is used for
synchronizing the timers for all the stations in a BSS.
TSPEC
Traffic Specification. TSPEC allows an 802.11e client or a QoS-capable wire-
less client to signal its traffic requirements to the AP.
TSV
Tab-Separated Values. TSV is a file format that allows the exchange of tabu-
lar data between applications that use different internal data formats.
TTL
Time to Live. TTL or hop limit is a mechanism that sets limits for data expiry
in a computer or network.
TTY
TeleTypeWriter. TTY-enabled devices allow telephones to transmit text
communications for people who are deaf or hard of hearing as well as trans-
mit voice communication.
TXOP
Transmission Opportunity. TXOP is used in wireless networks supporting the
IEEE 802.11e Quality of Service (QoS) standard. Used in both EDCA and
HCF Controlled Channel Access modes of operation, TXOP is a bounded
time interval in which stations supporting QoS are permitted to transfer a
series of frames. TXOP is defined by a start time and a maximum duration.
UAM
Universal Access Method. UAM allows subscribers to access a wireless net-
work after they successfully log in from a web browser.
U-APSD
Unscheduled Automatic Power Save Delivery. U-APSD is a part of 802.11e
and helps considerably in increasing the battery life of VoWLAN terminals.
UCC
Unified Communications and Collaboration. UCC is a term used to describe
the integration of various communications methods with collaboration tools
such as virtual whiteboards, real-time audio and video conferencing, and
enhanced call control capabilities.
UDID
Unique Device Identifier. UDID is used to identify an iOS device.
UDP
User Datagram Protocol. UDP is a part of the TCP/IP family of protocols
used for data transfer. UDP is typically used for streaming media. UDP is a
stateless protocol, which means it does not acknowledge that the packets
being sent have been received.
UDR
User Derivation Rule. UDR is a role assignment model used by the control-
lers running ArubaOS to assign roles and VLANs to the WLAN users based
on MAC address, BSSID, DHCP-Option, encryption type, SSID, and the loca-
tion of a user. For example, for an SSID with captive portal in the initial role, a
UDR can be configured for scanners to provide a role based on their MAC
OUI.