1. DCS Alternate Data Distribution System (DADDS)
Database Development Status
Presentation to the STIWG/TWG
July 9, 2008
The DADDS project has kicked off the development of the database web interface to support the turn off of DAPS. It is planned to be approximately six months of effort, at which time DCS users will be redirected to use new access procedures that are being developed.

2. Introduction
The DCS Alternate Data Distribution System (DADDS) was initially developed to disseminate DCS message data directly from the DAMS-NT
DADDS is designed to act as emergency DAPS backup for DOMSAT and NWSTG data streams
DADDS has been used operationally in place of DAPS and is available for backup
DADDS forms the first incremental component to replace DAPS
The DADDS project was established on an emergency basis to provide backup services to disseminate DCS data from Wallops in the event of total DAPS failure. It collects DCS data directly from the DAMS-NT demodulator servers, similar the LRGS concept, but using a higher resolution version of interface providing more accurate timing and quality information. The DADDS project quickly developed an alternate data distribution services to NWS and DOMSAT that provided transparent failover for operations.
The DAPS is well beyond its life expectancy and it is critical that it be decommissioned as soon as possible before it fails entirely. The DADDS is capable of providing the real-time functions and now the database interface and management functions are going to be added in an incremental fashion. The project approach all along has been to build and test the most critical functions in this fashion in order to minimize the risks, time and cost, while producing immediate operational benefits to the program.

3. Architecture
The DADDS system architecture will have sites at both Wallops and Suitland that receive and demodulate the data. Wallops is designated as the primary location and Suitland will be the backup. Both sites will have the capability to process, disseminate and store the real-time message data. The sites will be interconnected to allow remote monitoring and control, and replication of databases. NOAA is in the process of procuring the Suitland DOMSAT transmit capability, to reuse the same circuit and frequency in the event of a DOMSAT failure at Wallops. The switch would be controlled by Americom and should be transparent to the DCS users.
The DADDS database architecture has not been fully defined and thus is not depicted here. It is expected that the private database would reside on the SAN controlled by a database server, with a public database server located in the DMZ behind a firewall.

4. Availability
DADDS includes redundant hardware with automatic failover switching capability
The architecture design has dual processing paths for immediate re-routing of data
Provides high-availability hardware configuration with rapid recovery in event of equipment failure
Hot-swappable hardware with redundant components and power supplies
Parallel blade servers/disks and SAN disk array
SQL server high-availability DBMS features
DADDS is designed as a high availability/high integrity system with redundancy at each site and between sites. Automatic switching will provide seamless failover to redundant equipment/processing paths in the event of equipment or system failure.

5. Operation
DADDS uses daily PDT/UDT compressed files exported from DAPS as the database source
The DADDS concept allowed users to update records via web application in event DAPS unavailable for extended period
NOAA conducted Technical Interchange Meetings with Operators, Managers and Major Users to identify database requirements
To replace DAPS, DADDS enhanced to support user web interfaces and legacy batch functions
Similar to the LRGS, DADDS uses the daily PDT/UDT compressed files for determining the DCS schedule. DADDS checks each incoming message, determines any error codes, and builds the header and any informational messages. DADDS then generates the NWS and DOMSAT serial streams and disseminates them.
DADDS was initially intended to have a web-enabled interface for users to update their table information to maintain operations in the case of an extended DAPS outage or complete failure. Additional DAPS database functionality could be added to the DADDS incrementally.

6. Objectives
Maintain all database records essential to operation and maintenance of DCS
Provide database management software to fulfill real-time message handling requirements
Incorporate general functionality of the present DAPS fields, records, tables, and databases
Allow expansion/modification of the current fields, records, tables and databases
Support web interface to allow user access for updates, queries, searches, reports and utilities
The DADDS database is central to all DCS processing functions, both for real-time message data processing, and for user/platform information and updates. In order to support a simple transition to the operational DADDS, the table structure of the database will be minimally altered initially. However, it will be expandable to allow field/record changes for future needs. This expansion includes adding or extending tables, and appending contents of tables to message data, such as, for example, decoding the raw message data, if desired. A field in the PDT could contain information indicating the proper file for attachment to a given message.
The performance of the DBMS will be such that the non-real time functions will not interfere with the primary mission of real-time message data processing, dissemination, quality control and storage.
The DADDS DBMS will provide a GUI for users to access the system, update their records, perform canned or ad hoc queries and wildcard searches, generate statistical reports, and use other utilities.

7. Requirements User login and authentication
Access level and user privileges
User agency affiliation with individual accounts
Web database application and user interface
Incorporate DAPS tables and records
Update and expand database records and fields
Support legacy database batch updates
Message data access and retrieval
Replication, redundancy and robustness
System management and control
DADDS contains relational databases for all data and metadata, including the DCP message data storage. The database enables the real time data dissemination functions to be performed by DADDS. Valid users will log in through a web server GUI to their individually managed accounts, whether they are SUA holders, platform owners or secondary users. The user will be authenticated by the system and allowed to perform functions according to their access privileges. Typical functions performed through the database web application will include updating PDT and UDT information, requesting report generation, and retrieving message data or metadata information. The batch function will be supported and the program is working with users to ensure that their legacy methods continue to operate correctly.
The database is being designed for high availability and will operate in a high security environment; users will access it through a DMZ. The database will be replicated between the primary and secondary servers, and to the backup site. Redundancy will provide failover capabilities at the site or server level, with additional robustness for monitoring and control of the demodulator cards and cages. Ultimately the system will be able to recognize and recover from outages at the channel level. Only operators and managers will have the ability to monitor and control system parameters.

8. Authentication User application and registration process
Account authorization and privilege level
Password management functions
ing initial password instructions and changing passwords
Password expiration and warnings
Reminders and forgotten password features
Current NOAA password policy and rules may apply
Minimum of twelve characters with at least one capital letter, one lower case letter, one special character and no characters repeated more than twice
Passwords expire every sixty days and cannot be re-used for two years
No names or words found in the dictionary
DADDS will provide user account management and authorization. NOAA has implemented a strict user password policy that, if required for DCS, will affect user account management.

9. Access
Browser-based GUI for Login with common look and feel for all user classes
Secure access control for registered users
NOAA password rules enforcement for user access to Government system
Database controls for selective user access to authorized records
Users will access DADDS through a GUI via the Internet with userID/password controls. DADDS will provide registered users with read/edit access according to their established user privilege. The DBMS will limit access to unauthorized records or data.

10. Schedule DBMS Requirements Apr – Jun 2008
Redundant HW/SAN Jul – Aug 2008
NSOF Acceptance Aug – Sep 2008
Web Application Jul – Dec 2008
DBMS Development Jul – Jan 2009
DBMS Acceptance Feb – Mar 2009
This schedule shows some of the major activities now underway. TIM’s were conducted during April, May and June of this year to identify requirements for the DBMS. The installation of redundant DADDS hardware and network storage represent the completion of the first phase of DADDS at Wallops and is occurring now. Bringing the NSOF on-line later this year will complete the second phase.
The web application and database development is the final DADDS phase and is completion is anticipated in early 2009.