Cisco BPX 8620 Installation And Configuration Manual page 585

sustainable cell rate.
SCR
Rate above which incoming cells are either tagged or discarded. Long term limit on the rate a
connection can sustain.
A set of data structures that map VSI service types to sets of pre-configured VC and Qbin parameters.
SCT
Consists of two sub-components—a VC Descriptor Template and a Class of Service Buffer descriptor
template.
synchronous data interface.
SDI
The back card for the HDM (IGX switch) cards. The SDI is available with V.24, X.21, and V.35
interfaces.
synchronous data packet assembler/disassembler.
SDP
SDP is used to connect simple synchronous data devices that do not support the full functionality of
a particular protocol to a network.
PADs buffer data, assemble, and disassemble packets sent to end devices.
See SSAR.
segmentation and
reassembly
See SIU.
serial interface unit
A concept for grouping connections that share a common set of traffic characteristics and QoS
service class (aka
service type) requirements. The terms "service class" and "service type" are sometimes used interchangeably. In
this release, there are some major service categories, such as VbrRt, VbrNRt, CBR, ABR, and UBR,
and under these major service categories are service types such as VbrRt1, VbrRt2, VbrRt3, and
VbrNRt1, VbrNrt2, and so on. Sometimes the terms service class and service type are used
interchangeably.
The collection of data items that support the service class template concept, and implemented on a
service class
per-VI basis on the BXM. These items include a copy of the specific Service Class Template selected
database
for a VI, as well as additional data as required.
See SCT.
service class
template
The Service Expansion Shelf is the controller on which the BPX's PNNI implementation runs. It is
SES
SPARC-based.
Refers to FastPacket to ATM interworking with respect to the IGX node. In the simple gateway mode,
simple gateway
FastPackets are encapsulated in their entirety into cells. Compare with complex gateway.
serial interface unit.
SIU
A set of circuits common to all BPX cards used for transmitting and receiving via the crosspoint
switch.
A PVC in the INS Dial-Up Frame Relay application that is dormant in the networks database until it
soft PVC
is activated by a call into the network by a user.
An network topology in which there is only one path available between any two sources in a frame
spanning tree
relay multicast group. Spanning trees are required to prevent frames broadcast from a single source to
multiple receptors from circulating endlessly around the network a result of frame relay circuits not
having properly closed loops.
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Cisco BPX 8600 Series Installation and Configuration
Glossary
GL-19