Product requirements document

The specifications ( partly requirement specification of requirements, product sketch, to customer specification or English Requirements Specification called ) describes the overall requirements of the client to the supplies and services of a contractor. It is, for example, in the software field, the result of a requirement analysis and thus a part of requirements management.

The specification, the client can use in a tender and send them to some potential contractors. Possible contractors create based on the specifications a requirement specification, which describes in a more concrete form as the contractor intends to address the requirements in the specifications. The client then selects the proposals from the most suitable for him.

The requirements in a specification sheet should be formulated as general as possible and as restrictive as necessary by their formulation. A result, the contractor has the opportunity to develop optimal solutions, but are not limited to specific requirements through in his solving skills.

In the context of a contract or supply contract work and the associated formal acceptance describes the specifications precisely verifiable services and supplies.

Subject

According to DIN 69901-5 (terms of project execution ) describes the specifications the

The specification describes a rule therefore, what is and what something should be done. Compared to a technical concept but it is to formal aspects that are necessary to an alert enriched. The addressees of the specifications are the ( external or in-house ) Client and the Contractor.

In order to keep a clear specification, it is preferably taken in almost orientierendem text and supplemented with detailing, for example, in tabular form, with drawings or graphics. There are also formalized approaches to such modeling languages ​​.

Follow-up steps

If a specification adopted, follows with the specifications to the next phase, which describes how and with which something is to be realized. In this case, every request of the specifications can be assigned to one or more services of the specifications usually. So also the order of the two documents in the development process is clear: the requirements ( requirements ) are met by services ( features ).

According to DIN 69901-5, the specification contains the " the contractor developed implementation requirements due to the implementation of the specified by the client specifications ."

Demarcation

Depending on the application and industry to specifications in the structure and content can vary greatly. In practice, the terms specification, functional specification and specification are often not clearly distinguished from one another or even used interchangeably. The fuzzy use of terms and the lack of separation of technical information and operational intentions is often the cause of misunderstandings.

At a purchase contract according to BGB § 433 or a legally equivalent supply the criteria of specifications are generally not apply because the supplies in the purchase contract are determined by a unilaterally imposed by the suppliers specification in the type and the quantity supplied unilaterally prescribed by the Purchaser.

At a service contract with the criteria of specifications usually are not applicable, since the benefits are not subject to formal acceptance in the service contract.

Construction

A specification sheet can be divided in various ways. The following information is typically considered:

• Usability
• Reliability
• Efficiency
• Changeability
• Transferability
• Maintainability

Industry specification

In some industries, standardized guidelines for specifications and their settlement have been established. In Software Engineering, IEEE Software Requirements Specification is often used. This is a document that specification and tender documents summarizing.

In the specifications space used is often based on the NASA standard to facilitate international cooperation. It has been formed following principle:

• The client makes a request specification ( spec requirements ) that contains the mission requirements and framework conditions (eg it is a manned laboratory module for the ISS are supplied to be transported there by the space shuttle );
• The Contractor will respond with an implementation specification ( design-to - spec), which specifies the selected design by the contractor (eg, a cylindrical pressure module with a certain diameter and length);
• The Customer shall accept formally containing more details implementation specification. However, in the event of a conflict occurring later, the requirements specification takes precedence.

More meaning of specifications

In construction, the term specification is used in a different meaning than specifications for stability analyzes. This actually contains loads, namely the stresses of a structure for which the structure is to be measured, such as weight, payload, wind pressure and water pressure. Moreover, the specifications contain all other requirements, conditions and prerequisites that are required for a static calculation of the structure in question, for example, material properties and soil characteristics.

Norms and Standards

• DIN 69901-5: Project Management - Project management systems - Part 5: Terms
• VDI 2519 Sheet 1: Procedure for creating Lasten-/Pflichtenheft
• VDI 2519 sheet 2: requirement / specification for the use of materials handling and storage systems
• VDI 3694: System requirement / specification for the use of automation systems
• VDI 4403 Part 1 Design: modernization and expansion of material handling equipment and logistics systems operating in date
• VDI 4403 sheet 2 Design: modernization and expansion of material handling equipment and logistics systems in operation date, reconstruction and expansion of a large central warehouse
• IEEE 830-1998: Software Requirements Specification, specifications for software systems