Chapter 3 System Features
PSAX 20 Software Features
3-34
255-700-019
PacketStar
™
PSAX 20 Access Concentrator User Guide
, Issue 1
Release 6.3.0
Modules: Channelized DS3, DS3 IMA, DS3 ATM, DS3 Frame Relay
A network element (NE) will transmit an AIS alarm when it detects an AIS
defect that persists for 2.5 +/- 0.5 seconds. In this situation, the NE will also
transmit RDI upstream.
•
The AIS alarm stops when the NE receives a valid signal for 10.0 seconds
+/- 0.5 seconds.
Modules: E1 IMA, Enhanced E1, High-Density E1
A network element (NE) will transmit an AIS alarm when the defect of two
or fewer zeros in each of two consecutive double frame periods (a total of
512 bits) is detected.
•
The AIS alarm stops when the NE receives either of the following:
~
two consecutive double frame periods (a total of 512 bits) containing
three or more zeros
~
A frame alignment signal error
Module: E3 ATM
A network element (NE) will transmit an all ones AIS downstream when it
detects a loss of signal (LOS) or loss of frame (LOF). In this situation, the NE
also transmits a far-end remote failure (FERF) alarm upstream.
Remote Defect
Indications
Modules: Channelized DS3, DS3 IMA, DS3 ATM, DS3 Frame Relay
A network element (NE) will transmit an RDI when it detects a severely
errored frame (SEF) or AIS (if implemented) for 2.5 s/- 0.5 seconds.
•
The RDI alarm stops when the NE’s received failure stops for 10.0 seconds
+/- 0.5 seconds.
E1 IMA, Enhanced E1, High-Density E1
A NE will transmit a RDI alarm upstream when a “1” in bit 3 in Non-Facility-
Associated Signaling (NFAS) frames is detected.
•
The RDI alarm stops .6 seconds after the condition has been removed.
Soft Permanent Virtual Circuits
The soft permanent virtual circuit (SPVC) feature is a semi-permanent virtual
circuit enabled by management action. It is a PVC-type circuit in which SVCs
are used for call setup and (automatic) rerouting. Once either a PVC or a
permanent virtual path connection has been configured, an SPVC can be
established between the two network interfaces serving the PVC by using
signaling procedures. Consequently, this type of connection has attributes of
both a switched virtual connection and a permanent virtual connection.
Specifically, an SPVC is established and released between the two network
interfaces (NIs) serving the PVC. The user assigns unique ATM addresses,
including the SEL octet in the case of a private ATM address (see Section 3.1
of UNI 4.0 signaling specification), to the corresponding NIs, thus identifying
the startpoint and endpoint of the SPVC.
Summary of Contents for PacketStar PSAX 20
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