Liaison statement
LS on coordination on information and data modelling

ITU-T Q14/15 has been working on modelling of Ethernet OAM to augment the IEEE
802.1Qcx CFM with the ITU-T G.8013 OAM. The CFM functions between the IEEE
802.1Qcx YANG modules and ITU-T G.8051 and G.8052 managed MI signals have been
analysed. The followings are a summary of the analysis. It would benefit from
setting default values for the following attributes in the CFM YANG modules.

(1) Continuity Check
Some IEEE specific operations are not supported in ITU.
- rmep-failed-ok-time, mac-address in remote mep-db: These are read-only
parameters, so it is possible to omit them. - Port Status TLV, Interface Status
TLV, Sender ID TLV: G.8052.1 can exclude them because they are optional TLVs.
One ITU specific operation is not supported in IEEE. - Proactive LM: It needs
to be augmented in G.8052.1 as the part of performance monitoring functions.
The definition of defect detection is different between IEEE and ITU. -  cDEG,
cUNPr: Not supported in 802.1Q

SG15-LS188
-  xconCCMdefect: Composition of cUNL and cMMG
- errorCCMdefect: Composition of cUNP and cUNM
- FNG(Fault Notification Generator): Not specified in G.8051

(2) Loopback
Some ITU specific operations are not covered in P802.1Qcx.
-  Series: Configuration of the LBM Tx period and collection of total number of
LBM frames. They should be supported with the augmentation approach suggested
in P802.1Qcx. -  Two-way Test: Support of Test TLV (including the number of
CRC/BER/OO frames) and running infinite number of times. It needs to be
augmented in G.8052.1 as the part of performance monitoring functions. Some
IEEE specific parameters are not supported in ITU. -  lbm-dest-mep-id: G.8052.1
has only to exclude this operation because it is optional in 802.1Q. - 
Lbm-request-id: Since they are read-only parameters, there is no impact if they
would be pruned in G.8052.1.

(3) Linktrace
Some IEEE specific operations are not supported in ITU.
-  ltm-target-mep-id: G.8052.1 has only to exclude this operation because it is
optional in 802.1Q. -  ltm-flags, ltm-transaction-id, ltm-egress-identifier,
ltr-receive-order, ltr-forwarded, lter-terminalmep, ltr-relay: Since they are
read-only parameters, there is no impact if they would be pruned in G.8052.1.

The result of the detailed comparison is shown in the Excel file:
CFM YANG vs MI . x lsx

ITU-T Q14/15 has been hosting regular virtual meetings since November 2018 on
coordination of information/data modelling on topics such as Ethernet OAM.
Experts of SDOs, including IEEE 802.1Qcx, have been invited to participate in
these meetings.

ITU-T Q14/15 will continue to host coordination virtual meetings on the
following dates. Modelling experts of the receiving SDOs of this liaison
statement are invited to join. Logistics details: -  Dates: 2019 September 9;
November 11; 2020 January 13 -  Time: 3:00 PM - 4:00 PM CET (Geneva
Switzerland) -  URL: Series of virtual meetings at
https://global.gotomeeting.com/join/897704405 -  Access Code: 897-704-405 -
Dial in: United States: +1 (312) 757-3117