User`s guide

Functional Overview
5–6 MS-4900, Rev. A
Table 5-1 reflects the availability and usage of the five possible serial ports,
depending on the nature of the received data: transparent asynchronous, statistically-
multiplexed, or transparent synchronous, or combinations thereof.
NOTE: The functionality of Serial 4 port is dependent on the hardware
configuration established at the factory.
Table 5-1. Matrix of Serial Port Availability
Trans-
parent
Async
Stat mux Transparent
Sync
Possible Serial Port
Configurations: Serial 1 Serial 1 Serial 2 Serial 3 Serial 4 Serial 4 Serial 5
Configuration A
4 4 4
Configuration B
4 4 4
Configuration C
4 4 4 4
Configuration D
4 4 4 4 4
Configuration E
4 4 4 4 4
TVCS and
PVCs
Temporary Virtual Circuits (TVCs) and Permanent Virtual Circuits (PVCs) are the
two connection options available through a stat mux channel on a WavePhore
Network. A TVC is like a switched connection in which a session is established only
for the duration of a given transmission. A PVC establishes a perpetual
communications session between the head-end and the receiver. An IDR V1000 can
run TVC-only sessions, PVC-only sessions, or a mixture of PVC and TVC sessions.
TVC sessions open and close. Therefore, the number of active sessions reported on
the Show Status screen at any given time is dynamic. TVCs are enabled by
downloading pool and group codes to the IDR V1000.
PVC sessions never close. Therefore, the reported number of active sessions is
always the same number in an exclusively PVC environment. The IDR V1000 can
support one PVC session per logical receiver in PAD mode and up to four PVC
sessions per logical receiver in Node mode. (A maximum of 10 PVC sessions can be
enabled across all logical receivers.)
PAD and Node
Modes
Each stat mux output port of the IDR V1000 is configured to deliver data in either
PAD or Node mode. The mode determines the manner in which the received data is
sequenced and output. Depending on the type of session delivering that data (PVC or
TVC), the selected mode ultimately affects the formatting and appearance of the
output data. (Each port outputs data in the selected mode, regardless of whether that
data comes to the receiver as a PVC or a TVC session.)