Cabletron Systems 1800 manual Q, R

glo-8 Smar tSwitch 1800 4. 0 User G uide, R ev 01
PAD stands for “packet assembler/ disass embl er,” which allows a non -X. 25 devi ce to access
a Smart Switch 1800, by conve rting i ts prot ocol to the X.2 5 packe t mode protoc ol, and
vice versa. SmartSwitch 1800 supports integral async, SNA, and BSC PADs.
PBX stands for Private Branch Exchange, and refers to a small private telephone switch.
PDN stands for “public data network,” which is a network operated by common carriers or
telecommunications administrations for the purpose of providing data transmission
capabilities to the public.
Phys ical DC E/DTE
see “DCE” and “DTE.”
Port is the entry or exit point for node traffic.
Protocol
is an agreement on format, meaning, and relative timing of information exchanged
between two communications devices.
PU stands for “physical unit,” which is an IBM referenced to any SNA host or terminal
devic e.
Public Data Network
see “PDN.”
PVC stands for “permanent virtual circuit,” which is a permanent logical connection
between two subscribers, analogous to a leased line. Transmission of packets on a
PVC needs no call setup or call clearing.
Q
QLLC is “Qualified Logical Link Control,” which is a method of encapsulating SNA traffic
for tra ns missi on over X. 25.
R
RIP stands for “routing information protocol,” which provides for dynamic routing in a
TCP/IP implementation.
Root is the bridge determined (by implementation of the spanning tree algorithm) to be the
lowest-cost path between points in a bridged link.