PM7340 Datasheet, PDF (83/334 Pages) PMC-Sierra, Inc – S/UNI INVERSE MULTIPLEXING FOR ATM, 8 LINKS

PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
DATA SHEET
PMC-2001723
ISSUE 3
PM7340 S/UNI-IMA-8
INVERSE MULTIPLEXING OVER ATM
Figure 18 - Snapshot of DCB Buffers after deletion of links from group
DCB
Link 0
DCB
Link 1
DCB
Link 2
DCB
Link3
Write
Pointer 0
Group
Read
Pointer
15
14
13 _Write
11 ^{Pointer 1}
9
7
5
3
1
Removed
from
12
group
10
8
6
4
2
Removed
from
group
10.2.4.3 IMA Link Error Handling
For IMA operation, the RDAT is responsible for detecting Loss of IMA Frame
defects (LIF), Idle Cells on IMA Links, Loss of Cell Delineation defects (LCD), and
DCB overruns/underruns that contribute to Loss of Delay Synchronization
(LODS). This information is forwarded to the RIPP with the ICP messages for
processing and reporting.
10.2.4.3.1 IMA Error/Maintenance State Machine (IESM)
A state machine is maintained for the LIF defect detection. This state machine is
called the IMA Error/Maintenance State machine [IESM]. The state diagram for
the IESM is shown in Figure 19. The RDAT maintains an IESM for each link. The
LIF Defect state is the initial state for this process, thus all links will initially come
up in the LIF condition.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE 66