1. OpenOMCI Framework Proposal
A refactored OMCI Communications Channel
&
Frame Generator
Voltha Lockdown Meeting
January 10th, 2018
ADTRAN, Inc

2. Proposed Framework Vendor ONU Device Adapter MIB Synchronizer
OMCI State Machine
MIB Synchronizer
Tasks
MIB Sync
Alarm Sync
PM Collection
ME Database
New Classes
LCI Service
Software Download
Others...
Existing VOLTHA v1.1x Classes/Code
OMCI CC
MEFrame
OMCI Message
OMCIFrame
EntityClass

3. Base Philosophy & Requirements
For all applicable classes being proposed:
Make it easy for ONU Adapters to derive and overload functionality
Python classes for use in a vendor’s ONU Device Adaptor (not a separate docker container)
Additions/modifications to any existing classes should avoid breaking any existing functionality
Focus on needs of initial use cases
Clear documentation for each class and for a class’s methods
90%+ Unit test coverage for any new classes
Allow ONU Device Adapter access to some of the classes and class attributes (not all interactions go through the state machine)

4. ONU State Machine
This is the main interface from an ONU Device Adapter into the OpenOMCI Stack
Provides
Startup/Shutdown of OMCI Stack. Lifetime starts at ONU Activation completion.
A set of task classes responsible for various ONU OMCI Stack actions such as:
MIB Synchronization
ONU Physical and Software Capability Discovery
Alarm Synchronization
Various Service Instantiations (LCI, VoIP, Video, ...) - Based on required use cases
Software Image Download, Commit, and Activation
PM Statistics (and OLT time synch, but not Time of Day)
Others as needed (power shedding, ToD)
Each task runs to completion before next task handled.
Task queue has tasks in a defined priority so next highest runs when Stack is free
Each task (and main state machine) is a single class that can be overloaded as needed by an ONU DA to customize

5. OMCI State Machine Initialization method will:
Register all known tasks. You can derive your own if you wish use customized tasks
Start/Stop method to control the state machine
Task start method to add or schedule a new task to be executed.
Responsible for ME database
Probably several additional methods to support task functionality
Reference T-REC-G.Imp S!!MSW-E.doc (ITU)

6. ME Database
An External DB to contain ME attribute values that were discovered during MIB Synchronization
Needed to allow for hitless recovery after an ONU Device Adapter container migration or restart
Leverage information in the EntityClass ME definition to create the storage attributes

7. Common OMCI CC class
Add a common class to handle all OMCI Tx and Rx tasks that can be used (and extended as needed) for all ONU Device Adapters to .../voltha/extensions/omci
Basic Requirements:
User settable timeout for OMCI responses
Matches Rx TID to Tx TID
Send() returns a deferred that fires on Rx
Separate queues for autonomous messages
Statistics to help in diagnosing issues
Much of this code already exists in the ADTRAN ONU Device Adapter. Still one or two check-ins still needed, but should be complete by 1/17/18

8. MEFrame - ME Message Creation
An Python base-class that wraps message attributes and provides methods for generating proper ME actions (create, delete, get, set, …)
Basic Requirements:
Extensive checking of input parameters to validate data is correct during frame generation
Flexible method to supply ME attributes to ME Frame initializer
A majority of MEs can be coded in two lines or less
Much of this code already exists in the ADTRAN ONU Device Adapter. Still one or two check-ins still needed, but should be complete by 1/17/18

9. ONU MIB Synchronizer
Responsible for synchronizing the ONU Device Adapters MIB with that of the ONU Hardware
Performs ONT Bring up (MIB Reset, MIB upload, and MIB Download)
Monitors/sinks AVC notifications from the ONU
Maintains ONU Device Adapter MIB synchronization/resynchronization with that of the ONU Hardware

10. ONU Alarm Synchronizer
The ONU Alarm Synchronizer is responsible for monitoring the alarm status of the ONU hardware
Monitor/sinks Alarm notifications from the ONU
Performs alarm audit and resynchronization as needed with the ONU

11. Misc. Existing EntityClass work: Existing OMCFrame work:
Validate the current settings
Add additional Entities that are needed to cover the initial use cases
Property to allow access to some of the settings such as attribute names. Useful for error checking
Add additional attributes (from the ITU and AT&T OpenOMCI spec) that may help some tasks easier to implement or provide for better error checking (max/min values, whether or not it can be reported in an AVC notification, …)
Existing OMCFrame work:
Finish coding several of the frames (notably ones that my have tables)
Add any additional ones required to cover initial use cases

12. Original Picture from TST 1/4/18
Vendor ONU Device Adapter
Future OpenOMCI Classes
ONU State Machine
Alarm Synchronizer
MIB Synchronizer
Proposed Classes
Existing VOLTHA Classes
OMCI_CC
MEFrame
OMCI Message
OMCIFrame
EntityClass
AdapterAgent
(Proxy Rx/Tx methods)