Specifications

Engineering Guidelines
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Subnet – A subnet (short for “subnetwork”) is an identifiably separate part of an organization's
network. Typically, a subnet may represent all the machines at one geographic location, in one
building, or on the same local area network (LAN).
SWB – Mitel Sales Workbench.
T.37 – Internet Protocol for FAX (Store and Forward). A means of taking a TDM FAX, converting
it to data, passing it via IP and reconverting it back to TDM.
T.38 – Internet Protocol for FAX (Real Time). Similar to T.37 in function, but carried out in real
time, i.e. with minimum delay.
T1 – Primary Rate. Provides 23 or 24 channels of trunks per connection.
TAPI – Telephony Applications Programming Interface. TAPI is a standard programming
interface that lets you and your computer communicate over telephones or video phones to
people or phone-connected resources.
TAR – Tape Archive and Retrieval. A file transfer utility.
TCP – Transmission Control Protocol. The methods of transmitting data between two
end-points using IP with acknowledgement.
TDM – Time Division Multiplex. A means of combining a number of digitally encoded data or
voice channels onto a common digital stream, e.g. T1.
TFTP – Trivial File Transfer Protocol. A simplified version of FTP used to transfer data with
minimal overhead.
TOS – Type of Service. A field within the Layer 3 (IP) encapsulation layer to identify some
properties relating to service parameters; in this case, delay and priority of handling.
UCA – Unified Communicator Advanced. Fomer name for MiCollab Client, a PC-based
office management application, MiCollab Client Softphone is an enhanced version of MiCollab
Client that includes a PC-based phone.
UDP – User Datagram Protocol. A layer 4 protocol with minimal handshaking and overhead.
Used to stream voice. Considered connectionless.
Unicast – A process of transmitting messages from one source to one destination, as opposed
to a broadcast or multicast.
UPS – Uninterruptible Power Supply. A unit capable of providing output power for a period
of time when the local mains supply fails. Usually relies on storage devices such as batteries.
UTP – Unshielded Twisted Pair. Cable that reduces emissions and maintains an impedance
match through the twists per metre in the cable without resorting to shielding.
VLAN – Virtual LAN. A means of providing virtual LANs on a network using common physical
components. Such VLANs are logically unconnected except through some Layer 3 device.