User Manual

VF / DSL Cable Qualifier
302
HDSL High bit-rate Digital Subscriber Line - an xDSL technology in which modems on either end of two or
more twisted pair lines deliver symmetric T1 and 2 MBIT/S (E1) speeds. Currently, T1 requires two lines and
2 MBIT/S (E1) requires three.
ISDN- Integrated Services Digital Network
Load Coil - An induction device employed in local loops exceeding 18,000 feet in length, that compensates
for wire capacitance and boosts voice grade frequencies. Load coils prevent high frequencies from passing
through so they must be removed to allow xDSL technologies to operate on the local loop.
Local Loop - The line from the subscriber to the telephone company central office exchange
Multi-Point - A configuration that supports multiple terminal equipment devices.
National ISDN - A standard call control for NI-1,2, and 3.
NT1 Network Termination type 1 - The ISDN device responsible for the termination of the ISDN transmission
facility at the customer premise.
NT2 Network Termination type 2 - An ISDN device responsible for on premise communications distribution,
such as a PBX, LAN, or host computer.
Octet - An eight bit quantity. Used in reference to digital transmission, same as a byte.
Point to Point - A direct connection, normally from an NT1 to a TE.
POTS - Plain Old Telephone Service.
PRI- Primary Rate Interface - One of the access methods to an ISDN circuit. Comprising of 23 B-channels
and 1 D-channel (North American) and 30 B-channels and 1 D-channel (ETSI).
PSTN - Public Switched Telephone Network
S/T Interface The standard 4 wire (2 Rx, 2 Tx) ISDN interface used by ISDN terminals. It is the physical
interface on the terminal side of the NT1.
TE Terminal Equipment - Any ISDN compatible device that may be placed on the network such as a
telephone, PBX, TV, PC, etc.
TE1 Terminal Equipment type 1 - ISDN compatible terminal equipment.
TE2 Terminal Equipment type 2 - Non-ISDN compatible terminal equipment.