What Does a Usability Specialist Do?

Effectiveness, effectiveness and efficiency of services. In the Internet industry, it refers to whether users can use network resources at any time, in other words, the average failure-free rate of the network. In addition to the network equipment reliability, network failures are also related to many non-network factors, such as digging optical cables due to construction. Therefore, in order to ensure the failure-free rate of the network, in addition to selecting high-performance and high-reliability equipment, redundancy and backup must be fully considered in the network structure. Take the cable cut event as an example. Assume that it occurs once a year. No measures are used at all, but there are personnel to maintain it 24 hours a day. The time for finding and connecting optical cables is generally 1 day, so its service availability index is: 1-24 × 60 × 60 / (31.536 × 106) = 99.726%.

Performance: Although many systems are functionally available, the level of performance is reduced due to the loss of some functions. When the hard disk or cluster processor of an online shopping site fails, although it can still receive orders, its overall service efficiency will decline. Today's systems are often designed to continue to provide service when certain components fail, but performance levels will decline.

Function: Even if the fault prevents the system from operating as designed, it can still provide some value. For example, when trading in a reservation system

When used.

Sufficient performance under fault conditions.

It has sufficient functions in the fault environment.

Not all systems have to be available 24 hours a day and maintain the best performance levels for all their features. The basic role of availability is to enable designers of available systems to design systems that meet the needs of an enterprise's availability, while being affordable. ^[3]