PM7340-PI datasheet(97/334 Pages) PMC

97 / 334 page

PRELIMINARY

INVERSE MULTIPLEXING OVER ATM

PM7340 S/UNI-IMA-8

DATA SHEET

PMC-2001723

ISSUE 3

INVERSE MULTIPLEXING OVER ATM

PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE

number of links for the rate calculation and is then passed on to the TIMA or

RDAT to indicate the LIDs to include in the round robin. The IDCC will only

change its rate at IMA frame boundaries.

10.2.6 Support of IMA Test Pattern Procedure

S/UNI-IMA-8 supports the IMA test pattern procedure in both the TX direction

(NE initiated) and RX direction (FE initiated).

In the TX direction, the S/UNI-IMA-8 updates the TX test control info and TX test

pattern field in the outgoing ICP cells, as prompted by the relevant

Update_test_ptn command. Meanwhile, the S/UNI-IMA-8 will always compare

the RX test pattern field received in the incoming ICP cells with the TX test

pattern value being transmitted, and save the result on a per-link basis in the

group context memory.

In the RX direction, the S/UNI-IMA-8 always analyzes the TX test control info

field in the incoming ICP cells. If the test link command field is set to “active”, the

TX test pattern field in the incoming ICP cells on the selected link will be copied

to the RX test pattern field in the outgoing ICP cells. Otherwise the RX test

pattern field in the outgoing ICP cells will be filled with “0xFF”.

10.2.7 Support of Symmetric/Asymmetric Operation Modes

S/UNI-IMA-8 supports all three possible group symmetry modes: symmetric

configuration and symmetric operation; symmetric configuration and asymmetric

operation; asymmetric configuration and asymmetric operation.

For symmetric configuration, the number of TX and RX links in the group must be

the same; for asymmetric configuration, that restriction does not apply.

The support for asymmetric/symmetric operation modes is part of the S/UNI-IMA

functionality.The symmetric operation mode is treated as a special case of the

asymmetric operation, where the TX and RX LSM on the same physical link are

inter-dependent.

10.2.8 Support of Different IMA Versions

It should be noted that the technique used to report RX information over the Link

Information fields in the ICP cells when the group is configured in the symmetrical

configuration and operation mode differs in the IMA v1.1 implementations and the

IMA v1.0 implementations.

PM7340-PI Datasheet(PDF) 97 Page - PMC-Sierra, Inc