Specifications

Chapter 3 Configuration Installation and Operation Manual
3-10 Configuring Physical Layer Parameters of SHDSL Lines ASMi-54C LRS-102 Ver. 2.0
Configuring PCS Parameters
PCSs are defined in IEEE 802.3-2005. In LRS-102 they are used to transport
Ethernet traffic from a local Ethernet port over SHDSL.
The ASMi-54C internal SHDSL processing subsystem enables to configure for each
SHDSL line (actually – for each SHDSL port) the desired Physical Coding Sublayer
parameters. Therefore, ASMi-54C supports 8 PCS entities, one for each
associated SHDSL port, and on the supervision terminal screens, the PCS index
number is the same as the associated SHDSL port.
As for SHDSL ports, PCSs are processed in two groups of four (one group includes
PCSs 1 to 4, and the other – PCSs 5 to 8).
An ASMi-54 standalone unit supports the connection of up to four PCSs, which
must be in the same group (either 1 to 4, or 5 to 8).
The PCSs are independently configurable, except that only PCSs associated with
master lines (see
Table 3-3 ) can be selected.
In IEEE 802.3-2005 terminology, each PCS is associated with a PME (Physical
Medium Entity): for ASMi-54C modules, it is the SHDSL master line.
The PCS bandwidth depends on the rate provided by the associated line:
• When using the 64/65-octet TC layer, the available bandwidth is the payload
rate of the associated line. This bandwidth is a maximum of 22784 kbps
(when using the 8-wires mode with four SHDSL ports operating at the
maximum rate, 5696 kbps).
• When using the HDLC TC layer, the available bandwidth is the payload rate of
the associated line, less any bandwidth assigned to the associated internal
DS1 port of the same line.
Even when all the eight SHDSL lines of the ASMi-54C module operate in the
2 Wires mode (see
Table 3-2 ), the PCS transport bandwidth can be increased
using PAF (PME Aggregation Function), also defined in IEEE 802.3-2005. PAF
creates PCS groups. The PCS groups that can be configured on the ASMi-54C are
listed in
Table 3-4 .
Table 3-4. Supported PCS Groups versus Lines Parameter
Maximum Number
of PCS Groups
Number of SHDSL Ports
(Lines) in PCS Group
SHDSL Lines in PCS
Group
Master PCS in the
Group
2
4 1, 2, 3, 4 1
4 5, 6, 7, 8 5
4
2
1, 2 1
3, 4 3
2
5, 6 5
7, 8 7
Note