AGL System Architecture Team (SAT) Charter

The following sections constitute the charter of the Automotive Grade Linux System Architecture Team (AGL SAT or short SAT). The initial version of this charter is created by the SAT. It may be amended and modified from time to time by the SAT as required to fulfill the SAT's mission. The initial charter and all changes require the approval of the Automotive Grade Linux Steering Committee (SC).

The version of this charter is 0.1

The mission of the SAT is the stewardship of the AGL technical architecture. The SAT designs and implements the overall architecture for the AGL reference hardware and software solutions. Through the combined expertise of its members the SAT provides the scope and technical definition. There are three aspects to this mission:

• to document and build consensus around the business and technical drivers and non-functional requirements that the AGL solutions architecture need to satisfy and to interpret and clarify these drivers and requirements when necessary;
• to resolve issues involving architecture and design;
• to facilitate and coordinate cross-technology architecture development inside and outside of AGL.

• System - A software system is a system of intercommunicating components based on software forming part of a computer system (a combination of hardware and software).
• Subsystem - Vertical slice of similar functionalities through the system, for instance an audio subsystem, a navigation subsystem, etc.
• Element - Partition of the architecture or particular architecture view. An Element can be a Subsystem, a Component, a Layer.
• Component - A software component is a software element that conforms to a component model and can be independently deployed and composed without modification according to a composition standard.
• Layer - Horizontal partition of the architecture such as HMI, kernel, middleware, service layer etc.

The SAT's tasks and responsibilities are focused on the delivery of the AGL reference hardware and software solutions. They include

• Review and analysis of use cases and requirements provided by the Steering Committee (SC) member companies. Provide feedback to the Steering Committee (SC).
• Review and analysis of project proposals presented by the Steering Committee (SC). Provide recommendations to the Steering Committee (SC).
• Allocation of requirements to architectural elements.
• Development and review of functional and non-functional requirements and software requirements specifications for elements in cooperation with the Expert Groups (EG).
• Review and analysis of API definitions in cooperation with the Expert Groups (EG).
• Definition of the overall architectures for the reference hardware and software solutions.
• Identify reusable elements within and outside of the context of AGL to enable broader collaboration.

The SAT shall have at least 5 but no more than 10 Core Members. The initial Core Members are invited through an open invitation to join the SAT from the SC Coordinator to the Steering Committee (SC). Steering Committee (SC) Members may nominate themselves or others to join the SAT. Only employees of the Steering Committee (SC) Member Companies are eligible for Core Member.

Core Members remain members of the SAT for the period of a one year term. After that they can nominate themselves or may be nominated by the Steering Committee (SC) for another term. If there are more than 10 nominations for Core Member the Steering Committee (SC) will appoint them through consensus or vote.

There can only be one Core Member from the same company.

Each Expert Group (EG) is represented on the SAT by their technical lead. SAT membership from the Expert Group (EG) may change dynamically as Expert Groups (EG) are created and dissolved or as the technical leadership of the Expert Group (EG) changes.

Since multiple Expert Groups (EG) can be chaired by individuals from Core Member Companies and/or from the same company it is acceptable to have more than one individual from a company to be an Expert Group (EG) member.

The Chairperson is elected by the Core Members for the term of one year. Core Members may nominate themselves or other Core Members for the position of the Chairperson.

The Chairperson's role is the organizational coordination of the SAT. This includes these tasks:

• call and lead the SAT meetings;
• represent the SAT at meetings of other AGL bodies such as but not limited to the SC;
• report to the SC on SAT activities;
• provide feedback from the SC to the SAT;
• coordinate SAT decision making and consensus;
• represent the SAT to other organizations by mandate of the SC.

Concerning all other tasks and responsibilities the Chairperson is considered equal to the other Core Members.

The SAT's scope is limited to technical issues about architecture. The SAT should not consider administrative or organizational issues of AGL, which are generally addressed by the Steering Committee (SC) and the Advisory Board (AB).

However, the SAT may recommend Expert Groups (EG) to the Steering Committee (SC) for creation and approval as the SAT identifies the need for support in a particular area.

Decision making of the SAT follows the Cooperative Consensus Model. The Members, Core Members and Expert Group Members, of the SAT shall strive to reach the best possible decision for the benefit of AGL and its goals. If the Members cannot agree on a common decision, the Core Members may vote. The winning vote requires a 2/3 majority of the core members.

The deliverables of the SAT are as follows:

• Identification of business and technical drivers and non-functional requirements that the solutions need to satisfy e.g. security, modifiability and adaptability of the solutions to member companies' goals, trade-off between performance and adaptability, availability/reliability to optimize system uptime;
• Architectural Designs;
• Publication of Documents;
• Selection and Recommendation of Tools.

The SAT will coordinate work with other groups within and outside of AGL whose technologies have an impact on AGL architecture:

• SAT deliverables will be subject to review by the AGL Expert Groups (EG);
• the SAT may request the expertise of other groups within or outside of AGL;
• the SAT will make best efforts to accommodate the needs of Expert Groups that have begun work and need to complete it in a timely manner.

All AGL Expert Groups (EG) are expected to follow the Architectural Designs and Recommendations. If an Expert Group (EG) intends to contradict an established Architectural Design in a technical report, the Expert Group (EG) is expected to identify which principles are being contradicted and to provide technical rationale for the decision (e.g. the principle is wrong, conformance is impossible, etc.)

The following information will be public:

• the SAT charter;
• deliverables will be public according to the requirements of that process;
• the archive of public discussion of architecture issues;
• status reports at least once every three months;
• SAT Member contact information.

Other SAT information, including the archives of the SAT Member-only mailing list, will be confidential within AGL.

The SAT will use a mailing list for its communications.

The initial SAT meeting plan is as follows:

• The SAT will hold a regularly scheduled distributed meeting at least every other week.
• The SAT will organize occasional face-to-face meetings.
• The SAT may organize workshops to explore particular architectural challenges.