Objectives
Upon completion of this chapter, you will be able to answer the following questions:
- What are the four basic requirements of a reliable network?
- What is the function at each layer of the 3-layer network design model?
Key Terms
This chapter uses the following key terms. You can find the definitions in the Glossary.
availability
confidentiality
fault tolerant network
integrity
scalable network
Quality of Service (QoS)
Introduction (18.0)
Let me introduce you to my friend Bob! Bob works in the IT field in Vancouver, Canada and has some networking experience. He is consulting for his friends, Marcy and Vincent, who have purchased a furniture store. They want to expand their brick-and-mortar operations and establish an online store as well. Currently the store’s internal network handles in-store transactions and inventory. Marcy and Vincent want to add security cameras, VoIP phones, and also expand it to include ecommerce and shipping. Bob explains that this will be more expensive than his friends had anticipated. He is thinking about designing the future network for the furniture store. He explains that he must consider fault tolerance, scalability, QoS, and security. Also, their network is currently flat, not hierarchical. Hierarchical networks scale well and will better accommodate this growing business.
Wow! That is a lot for Marcy and Vincent to understand. They are not familiar with these networking issues. Are you? Take this module to learn more about reliable networks and hierarchical network design!
The network is a platform for distributing a wide range of services to end users in a reliable, efficient, and secure manner.
Have you ever been busy working online, only to have “the internet go down”? As you know by now, the internet did not go down, you just lost your connection to it. It is very frustrating. With so many people in the world relying on network access to work and learn, it is imperative that networks are reliable. In this context, reliability means more than your connection to the internet. This topic focuses on the four aspects of network reliability.
The role of the network has changed from a data-only network to a system that enables the connections of people, devices, and information in a media-rich, converged network environment. For networks to function efficiently and grow in this type of environment, the network must be built upon a standard network architecture.
Networks also support a wide range of applications and services. They must operate over many different types of cables and devices, which make up the physical infrastructure. The term network architecture, in this context, refers to the technologies that support the infrastructure and the programmed services and rules, or protocols, that move data across the network.
As networks evolve, we have learned that there are four basic characteristics that network architects must address to meet user expectations:
- Fault Tolerance
- Scalability
- Quality of Service (QoS)
- Security
Video – Fault Tolerance (18.1.2)
Refer to the online course to view this video.