An Introduction to Networking Version 4 0 Objectives

An Introduction to Networking Version 4. 0

Objectives � Describe how networks impact our daily lives. � Describe the role of data networking in the human network. � Identify the key components of any data network. � Identify the opportunities and challenges posed by converged networks. � Describe the characteristics of network architectures: fault tolerance, scalability, quality of service and security. � Distinguish between client/server and peer-to-peer networks

Why Use Networks? �Network �Group of computers and devices � Connected by transmission media �Stand-alone computer �Not connected to other computers �Uses local software and data �Advantages of networks over standalone computers �Device sharing by multiple users � Saves money and time �Central network management

How Networks Impact Daily Life �Explain the benefits of instantaneous communication and how it supports and improves our lives

How Networks Impact Daily Life �Explain ways that using information networks to share and collaborate improves teaching and learning

How Networks Impact Daily Life �Describe ways communication over a network supports the way we play

Data Networking Role, Components, and Challenges �Basic characteristics of communication – Rules or agreements are 1 st established – Important information may need to be repeated – Various modes of communication may impact the effectiveness of getting the message across

Data Networking Role, Components, and Challenges �Describe the role of data networking in communications

Data Networking Role, Components, and Challenges � Describe the various elements that make up a network – Devices These are used to communicate with one another – Medium • This is how the devices are connected together – Messages • Information that travels over the medium – Rules • Governs how messages flow across network •

Data Networking Role, Components, and Challenges �Describe the role of converged networks in communications – Converged network • A type of network that can carry voice, video & data over the same network

Network Architecture Characteristics �Explain four characteristics that are addressed by network architecture design – Fault tolerance – Scalability – Quality of service – Security

Network Architecture Characteristics �Describe how packet switching helps improve the resiliency and fault tolerance of the Internet architecture

Network Architecture Characteristics �Describe characteristics of the Internet that help it scale to meet user demand

Network Architecture Characteristics �Explain the factors that necessitate Quality of Service and the mechanisms necessary to ensure it

Network Architecture Characteristics �Describe how Qo. S mechanisms work to ensure quality of service for applications that require it

Network Architecture Characteristics �Describe how to select the appropriate Qo. S strategy for a given type of traffic

Network Architecture Characteristics �Describe why networks must be secure

Network Architecture Characteristics �Describe basic measures to secure data networks – Ensure confidentiality through use of • • User authentication Data encryption – Maintain communication integrity through use of • Digital signatures – Ensure availability through use of • Firewalls • Redundant network � architecture • Hardware without a single � point of failure

Types of Networks �Network models �Peer-to-Peer �Client/server

Peer-to-Peer Network Resource sharing on a simple peer-to-peer network

Peer-to-Peer Networks �Typical in a home with several computers �Direct computer communication �Equal authority �Individual resource sharing �May share resources �May prevent access to resources �Each computer can send data to every other computer on the network

Peer-to-Peer Networks �Advantages �Simple configuration �Inexpensive to set up �Disadvantages �Not flexible �Not necessarily secure �Not practical for large installations

Client/Server Networks Resource sharing on a client/server network

Client/Server Networks �Central computer (server) �Facilitates communication and resource sharing �Clients (other computers) �Personal computers � Known as workstations �Central resource sharing controlled by server �Data sharing, data storage space, devices �No direct sharing of client resources

Client/Server Networks �Server requirement �Network operating system � Manages client data, resources � Ensures authorized user access � Controls user file access � Restricts user network access � Dictates computer communication rules � Supplies application to clients �Server examples �UNIX, Linux, Microsoft Server 2003 and 2008. . .

Client/Server Networks �Server features relative to clients �More memory, processing, storage capacity �Equipped with special hardware � Provides network management functions �Disadvantages relative to peer-to-peer networks �Complex in design and maintenance

Client/Server Networks �Advantages relative to peer-to-peer networks �User credential assigned from one place �Multiple shared resource access centrally controlled �Central problem monitoring, diagnostics, correction capabilities �Efficient processing on large networks �Scalability �Popular in medium- and large-scale organizations