Data Visibility and N-Tier VEMS provides programming language and Accessibility Architecture operating system agnostic web services to provide data to those approved to view it. VEMS follows a 3-tier architecture that separates the data presentation, business rules and data storage to make enhancements and troubleshooting less disruptive to the overall solution. The layers use asynchronous components and events and many times are coupled with web services. Data The application and data are separated into Data Visibility and Accessibility Independence layers; transactions are governed by commits and rollbacks. Data Visibility and Common Look VEMS web site design is based on HTML5. It Accessibility and Feel is designed and architected with input from a cross functional workgroup. Data Visibility and Data All VEMS data, including data accessed by all Accessibility Persistence VEMS developed applications are stored on approved VA servers. Data Visibility and Test Driven Unit tests have been developed for web services Accessibility Development where appropriate. Data Visibility and Exception There is extensive use or TRY/CATCH Accessibility Handling exception handling throughout the web site and ancillary code as well as in the OCTS products. Scalability VEMS applications can scale out. VEMS is load Data Visibility and Accessibility balanced and more servers/VMs can be added as needed. Data Visibility and Stateless User interaction and session information is not Accessibility Business Logic stored within business logic. Data Visibility and Accessibility VEMS services and application meet Accessibility Section 508 requirements. Data Data standards All data stored in VEMS adhere to and follow Interoperability the standards set for the VA systems. Data Authoritative All VEMS data follow the VA standards, with Interoperability information the VA systems as the authoritative data source. sources of data design from VRM and FCMT enhances these criteria. Data Enterprise data All VEMS data follow the VA standards. Interoperability model Data Local copies of VEMS uses VEMS-specific copies of data as Interoperability data necessary but leverages VA authoritative data stores for external data that is fetched real-time. Meta Data All VEMS data are documented with metadata Data Interoperability Registry and can be published as required.
Data Visibility and Accessibility N-Tier Architecture VEMS provides programming language and operating system agnostic web services to provide data to those approved to view it. VEMS follows a 3-tier architecture that separates the data presentation, business rules and data storage to make enhancements and troubleshooting less disruptive to the overall solution. The layers use asynchronous components and events and many times are coupled with web services. Data Visibility and Accessibility Data Independence The application and data are separated into layers; transactions are governed by commits and rollbacks. Data Visibility and Accessibility Common Look and Feel VEMS web site design is based on HTML5. It is designed and architected with input from a cross functional workgroup. Data Visibility and Accessibility Data Persistence All VEMS data, including data accessed by all VEMS developed applications are stored on approved VA servers. Data Visibility and Accessibility Test Driven Development Unit tests have been developed for web services where appropriate. Data Visibility and Accessibility Exception Handling There is extensive use or TRY/CATCH exception handling throughout the web site and ancillary code as well as in the OCTS products. Data Visibility and Accessibility Scalability VEMS applications can scale out. VEMS is load balanced and more servers/VMs can be added as needed. Data Visibility and Accessibility Stateless Business Logic User interaction and session information is not stored within business logic. Data Visibility and Accessibility Accessibility VEMS services and application meet Section 508 requirements. Data Interoperability Data standards All data stored in VEMS adhere to and follow the standards set for the VA systems. Data Interoperability Authoritative information sources All VEMS data follow the VA standards, with the VA systems as the authoritative data source. of data design from VRM and FCMT enhances these criteria. Data Interoperability Enterprise data model All VEMS data follow the VA standards. Data Interoperability Local copies of data VEMS uses VEMS-specific copies of data as necessary but leverages VA authoritative data stores for external data that is fetched real-time. Data Interoperability Meta Data Registry All VEMS data are documented with metadata and can be published as required.