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S/UNI-ATLAS-3200 Telecom Standard Product Data Sheet
Preliminary
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990553, Issue 4
24
Acronym
Definition
It is typically paired with a Peak Cell Rate (PCR) parameter, and is enforced by the
policing (UPC/NPC) functions of the device.
TM
Traffic Management.
A Traffic Management device may be connected to the switch side
of the S/UNI-ATLAS-3200.
Tx Link
When configured as an Egress device, the output of S/UNI-ATLAS-3200 acts as a Link
Layer device as defined in the UTOPIA Level 3 and POS-PHY Level 3 specs, and
connects to a PHY. This interface is a Master interface for both UL3 and POS-PHY3.
Tx Master
On the Egress PHY side, the UTOPIA and POS-PHY interfaces act as a master,
controlling the transfers to the PHY. This interface is also referred to as the Tx Link
interface.
Tx PHY
When configured as an Egress device, the input of S/UNI-ATLAS-3200 acts as a PHY
layer device.as defined in the UL3 and POS-PHY Level 3 specs, and connects to a TM or
switch that acts as a Link Layer device. This interface is a Slave interface for both UL3
and POS-PHY Level 3.
Tx Slave
On the Egress System side, the UTOPIA and POS-PHY interfaces act as a slave; that is,
S/UNI-ATLAS-3200 looks like a PHY from the point of view of the upstream device. This
interface is also referred to as the Tx PHY interface.
TRCC
Total Received Cell Count.
Used in Performance monitoring. A rolling 16-bit count of
user cells (either CLP0, or CLP0+1) received by the Fwd PM sink point..
TUC
Total User Cell [Count].
Used in Performance monitoring. A rolling 16-bit count of user
cells (either CLP0, or CLP0+1) transmitted by the Fwd PM source.
TUCD
Total User Cell Difference.
This is the difference between the number of cells
transmitted in the block (as indicated in the fwd PM cell) and the number received. For
example, TUCD0 =
{[TUC0(t) – TUC0(t-1)] Mod 64K} - {[TRCC0(t) – TRCC0(t-1)] Mod 64K}.
User-Network Interface.
UNI
UPC
Usage Parameter Control.
This is what the standards call policing at the User-Network
Interface (UNI). The main purpose of UPC and NPC is to protect network resources from
malicious as well as unintentional misbehavior, which can affect the QoS of other already
established connections, by detecting violations of negotiated parameters and taking
appropriate actions. Such actions may include cell discard and cell tagging.
VC
Virtual Connection.
VCs may be Virtual Path Connections (VPCs) or Virtual Channel
Connections (VCCs). Each bidirectional VC serviced by S/UNI-ATLAS-3200 has one VC
Record in context memory in each direction.
VCC
Virtual Channel Connection.
VCRA
Virtual Connection Record Address.
This is the address of the VC’s context table in
memory. While it is listed as 17 bits, the MSB must be logic 0 in the S/UNI-ATLAS-3200.
VPC
Virtual Path Connection.