Requirements Analysis

Requirements are split into functional and non-functional. Functional requirements look at 'what the system must do', examples of functional requirements are listed below:

     • User Interface (eg. applications, operating environments, multimedia)

     • User data (eg. fileshares, profiles)

     • User devices (eg. printers)

     • User services (eg. email, web, printing)

Non-functional requirements concentrate on the 'how the system should behave' and include Performance, Availability, Continuity, Disaster Recovery, Scalability, Interfaces, Data Management, Support & Maintenance, System Administration, Security, Audit, Testing and Training.

Performance

The user experience is vitally important therefore assessing the performance of systems needs paramount consideration. Areas such as response times of logging on and off, using applications to the time it takes to print are covered by this. Other systems and infrastructure also needs to be considered, as the performance of a network or storage device for example, could severely limit the usability of a system.

Availability

System Availability looks at defining the operational hours of the services to be deployed, and the service levels required from various technical teams. Expected outages such as routine maintenance needs to be considered as this could affect the availability.

Continuity

Having contingency facilities like a secondary data centre for example, which could take over if the primary data centre fails is essential. System continuity through using hardware or sofftware based solutions such as load balancing needs to be considered. How to deal with data communication failures such as network outages is another important area.

Disaster Recovery

The most important facet of Disaster Recovery is data loss prevention and using techniques such as replication need consideration. As with any disaster recovery, it's only as good as when it's used so it's imperative to specify requirements around exercises to validate whether disaster recovery plans work. There's nothing worse than going into disaster recovery mode only to find the disaster recovery kit doesn't work or the plans are useless.

Scalability

Building a system which is scalable and addresses the user population needs and the levels of concurrency expected upon deployment and in a year or so, is essential. Scalability of databases, services and the design itself need to be assessed, to see whether scalability has been addressed.

Data Management

Moving to new systems generally requires the migration of data such as user data, which needs to be done without compromising the integrity of the data. Backup and recovery of data requires consideration along with logging and archiving.

Interfaces

Systems connect with other systems and the transparency of connections needs to be validated. Encryption of transmitted data across interfaces and linking with other systems such as email, authentication, printing and so on, need to be assessed.

Support & Maintenance

Every system requires support and maintenance, which includes the data centre elements such as server, network devices and the client side support elements such as user devices, printers etc.

System Administration (SA)

Systems need administration and the way they are administered needs a clear set of requirements, includingsystem administration facilities including tools, monitoring of system usage, service management reporting, incident categorisation and help desk.

Security

This area looks at authentication including authorisation, single sign-on, roles and access controls, along with security monitoring and the management of security.

Audit

Auditing access to systems needs to include as the very least unsuccessful logon attempts and unsuccessful attempts at data exchange.

Testing

Testing is critical to the success of any IT project and the specification of environments is very important along with the types of testing to be conducted and whether automated test tools are going to be used.

Training

Before any new system can be let loose on the users, a period of training is required and the numbers of users requiring training needs to be ascertained, as well as the needs of a training environment.

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