Cabletron Systems HSIM-W87 Switch User Manual


 
WAN Terms and Acronyms
HSIM-W87 User’s Guide C-3
DSX-1 Short-haul version of DS1(coaxial cable being used as the
media defines it as short-haul) by definition, coaxial cable is short-haul.
DSX-3 Short-haul version of DS3 (coaxial cable being used as the
media defines it as short-haul) by definition, coaxial cable is short-haul.
DTE Data Terminal Equipment, equipment that originates and
terminates data transmission such as a computer or printer (see DCE).
E-1 European digital signal level 1. Similar to T1 but provides 32
channels (2.048 Mbps) instead of 24 channels (1.544 Mbps).
ESF Extended Super Frame. A new T1 framing standard (see D4
framing) that uses 24 T1 frames, thus allowing individual identification of
the channel and signaling bits.
EXZ Excessive Zeros, an EXZ is the occurrence of any zero string
length equal to or greater than 3 for B3ZS, or greater than 4 for HDB3.
Fractional T1 Use of a portion (less than the full 24 channels) of a T1
line.
Frame Relay A network protocol that allows for many point-to-point
virtual connections over a single access channel.
HDB3 High Density Bipolar 3, used with E-1, a bipolar coding
method that does not allow more than 3 consecutive zeros.
HDLC High-Level Data Link Control, layer 2 (link layer) full-duplex
protocol derived from SDLC.
INV. HDLC A form of zero suppression in which all zeros in the
HDLC packet are changed to ones and all ones are changed to zeros.
ISDN Integrated Services Digital Network. Allows point-to-point
connections at 64 Kbps or 128 Kbps when necessary and disconnects the
line when not in use. With this service the user only pays for the time
connected.
JBZS Jam Bit-Zero Suppression, a form of zero suppression that
places a one in the seventh bit of a timeslot. Reduces the effective
throughput to 56 Kbps.