What is Network Criteria ?

         A network must be able to meet a certain number of criteria. The most important of these are performance, reliability, and security.
Performance
          Performance can be measured in many ways, including transit time and response time. Transit time is the amount of time required for a message to travel from one device to another. Response time is the elapsed time between an inquiry and a response. The performance of a network depends on a number of factors, including the number of users, the type of transmission medium, the capabilities of the connected hardware, and the efficiency of the software.
          Performance is often evaluated by two networking metrics: throughput and delay. We often need more throughput and less delay. However, these two criteria are often contradictory. If we try to send more data to the network, we may increase throughput but we increase the delay because of traffic congestion in the network.
Reliability
          In addition to accuracy of delivery, network reliability is measured by the frequency of
failure, the time it takes a link to recover from a failure, and the network's robustness in
a catastrophe.
Security
          Network security issues include protecting data from unauthorized access, protecting
data from damage and development, and implementing policies and procedures for
recovery from breaches and data losses.