Section: Information System Operations, Maintenance and Support
Explanation:
Latency the delay between the sender and the receiver decoding it, this is mainly a function of the signals travel time, and processing time at any nodes the information traverses.
In a network, latency, a synonym for delay, is an expression of how much time it takes for a packet of data to get from one designated point to another. In some usages (for example, AT&T), latency is measured by sending a packet that is returned to the sender and the round-trip time is considered the latency.
The latency assumption seems to be that data should be transmitted instantly between one point and another (that is, with no delay at all). The contributors to network latency include:
Propagation: This is simply the time it takes for a packet to travel between one place and another at the speed of light.
Transmission: The medium itself (whether optical fiber, wireless, or some other) introduces some delay.
The size of the packet introduces delay in a round trip since a larger packet will take longer to receive and return than a short one.
Router and other processing: Each gateway node takes time to examine and possibly change the header in a packet (for example, changing the hop count in the time-to-live field).
Other computer and storage delays: Within networks at each end of the journey, a packet may be subject to storage and hard disk access delays at intermediate devices such as switches and bridges. (In backbone statistics, however, this kind of latency is probably not considered.) For your exam you should know below information about Network performance:
Network performance refers to measurement of service quality of a telecommunications product as seen by the customer.
The following list gives examples of network performance measures for a circuit-switched network and one type of packet-switched network (ATM):
Circuit-switched networks: In circuit switched networks, network performance is synonymous with the grade of service. The number of rejected calls is a measure of how well the network is performing under heavy traffic loads. Other types of performance measures can include noise, echo and so on.
ATM: In an Asynchronous Transfer Mode (ATM) network, performance can be measured by line rate, quality of service (QoS), data throughput, connect time, stability, technology, modulation technique and modem enhancements.
There are many different ways to measure the performance of a network, as each network is different in nature and design. Performance can also be modeled instead of measured; one example of this is using state transition diagrams to model queuing performance in a circuit-switched network. These diagrams allow the network planner to analyze how the network will perform in each state, ensuring that the network will be optimally designed.
The following measures are often considered important:
Bandwidth - Bandwidth is commonly measured in bits/second is the maximum rate that information can be transferred Throughput - Throughput is the actual rate that information is transferred Latency - Latency is the delay between the sender and the receiver decoding it, this is mainly a function of the signals travel time, and processing time at any nodes the information traverses Jitter - Jitter is the variation in the time of arrival at the receiver of the information Error Rate - Error rate is the number of corrupted bits expressed as a percentage or fraction of the total sen The following answers are incorrect:
Bandwidth - Bandwidth is commonly measured in bits/second is the maximum rate that information can be transferred Throughput - Throughput is the actual rate that information is transferred Jitter - Jitter is the variation in the time of arrival at the receiver of the information Reference:
CISA review manual 2014 page number 275

Section: Protection of Information Assets

Section: Governance and Management of IT

The first thing that should be done before allowing users to connect personal devices to the corporate network is to implement an acceptable use policy. An acceptable use policy is a document that defines the rules and guidelines for using personal devices on the corporate network, such as security requirements, access rights, responsibilities, and consequences. An acceptable use policy can help to protect the organization from potential risks such as data leakage, malware infection, or legal liability. The other options are not as important as implementing an acceptable use policy, as they do not establish the boundaries and expectations for using personal devices on the corporate network. References: CISA Review Manual, 27th Edition, page 318