glo-4 Smar tSwitch 1800 4. 0 User G uide, R ev 01
DTE stands for “data terminal equipment,” which is the device at either end of a user-to-
network communications path. “Physical DTE” refers to the hardware configuration,
and “Logical DTE” ref ers t o the softwar e con figur ation . Note that phy sical a nd logic al
DTE are independent of each other; howev er, for each , if one end of the connection is
DCE, the other must be DTE, and vice versa.
DTMF stands for Dual Tone Multi Freque ncy signaling, which is the method commonly u sed
to send t on es usi ng push bu ttons on touch ton e phon es (as oppo sed to pu lse dial i ng).
E
E&M is the type of interface used for PBX tie-trunk connections. When configured for this
option, the SmartSwitch 1800 acts like the trunk side of a PBX.
Encapsulation
is the process whereby one protocol layer receives a message from a higher layer and
attached a header to the message for transmission to the next lower layer or out over
the network.
Ether net
is a LAN technology defined by IEEE standard 802.3, which supports CSMA/CD
(carrier sense multiple access/collision detection) protocol.
Eventis a change in status in software or hardware operation (e.g., configuration, function,
operating state, performance, etc.), that is reported to automatic and specified destina-
tions within the network the SmartSwitch 1800 is on. This term is synonymous with
“alarm.”
F
Four-wire
is a voice circuit with a separate pair of wires for inbound and outbound signals.
Fragment
is an IP datagram that is a piece of a larger datagram, the larger one having been seg-
mented to allow it to pass through a network that did not support th e larger datagram.
(See “Fragmentation.”)
Fragmentation
is the breaking up of IP datagrams into smaller segments, to allow the datagrams to
pass through a network that does not support the full size. If IP fragments the data-
grams, they will be reassemble d at the final destination; if another protocol fragments
them (for example, to pass through an X.25 network), they will be reassem bled at the
other si de of tha t net work.
Frameis a unit of data transmitted between OSI level 2 entities, and containing its own
control information for addressing and error checking.