CCNA_ITN_Chapter 1-1.pptx

Chapter 1: Introduction to Networks Dr. Nadhir Ben Halima Public Chapter 1 - Sections & Objectives  1.1 Globally Connected  1.3 The Network as a Platform Explain how multiple networks are used Explain the basic chara...

Chapter 1: Introduction to Networks Dr. Nadhir Ben Halima Public Chapter 1 - Sections & Objectives  1.1 Globally Connected  1.3 The Network as a Platform Explain how multiple networks are used Explain the basic characteristics of a network in every day life. that supports communication in a small to Explain how networks affect the way we medium-sized business. interact, learn, work and play. Explain the concept of a converged network. Explain how host devices can be used as Describe the four basic requirements of a reliable clients, servers, or both. network.  1.2 LANs, WANs, and the Internet Explain how topologies and devices are connected in a small to medium-sized business network. Explain the use of network devices.. Compare the devices and topologies of a LAN to the devices and topologies of a WAN. Describe the basic structure of the Internet. Explain how LANs and WANs interconnect to the Internet. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 2 Public Chapter 1 - Sections & Objectives (Cont.)  1.4 The Changing Network Environment Explain trends in networking that will affect the use of networks in small to medium-sized businesses. Explain how trends such as BYOD, online collaboration, video, and cloud computing are changing the way we interact. Explain how networking technologies are changing the home environment. Identify some basic security threats and solutions for both small and large networks. Explain why it is important to understand the switching and routing infrastructure of a network. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 3 Public 1.1 Globally Connected © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 4 Public Networking Today Technology Then and Now  We live in a world we barely imagined 20 years ago.  What wouldn’t we have without the Internet?  What will be possible in the future using the network as the platform? © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 5 Public Providing Resources in a Network Networks of Many Sizes  Small Home Networks – connect a few computers to each other and the Internet  Small Office/Home Office – enables computer within a home or remote office to connect to a corporate network  Medium to Large Networks – many locations with hundreds or thousands of interconnected computers  World Wide Networks – connects hundreds of millions of computers world- wide – such as the Internet © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 6 Public Providing Resources in a Network Clients and Servers  Every computer connected to a network is called a host or end device.  Servers are computers that provide information to end devices on the network. For example, email servers, web servers, or file server  Clients are computers that send requests to the servers to retrieve information such as a web page from a web server or email from an email server. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 7 Public Providing Resources in a Network Peer-to-Peer  Client and server software usually run on separate computers.  However, in small businesses or homes, it is typical for a client to also function as the server. These networks are called peer-to-peer networks.  Peer-to-peer networking advantages: easy to set up, less complex, and lower cost.  Disadvantages: no centralized administration, not as secure, not scalable, and slower performance. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 8 Public 1.2 LANs, WANs, and the Internet © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 9 Public Network Components Overview of Network Components  A network can be as simple as a single cable connecting two computers or as complex as a collection of networks that span the globe.  Network infrastructure contains three broad categories of network components: Devices Media Services © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 10 Public LANs, WANs, and the Internet Network Components  End Devices An end device is where a message originates from or where it is received. Data originates with an end device, flows through the network, and arrives at an end device © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 11 Public Network Components Intermediary Network Devices  An intermediary device interconnects end devices in a network. Examples include: switches, wireless access points, routers, and firewalls.  The management of data as it flows through a network is also the role of an intermediary device including: Regenerate and retransmit data signals. Maintain information about what pathways exist through the network and internetwork. Notify other devices of errors and communication failures. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 12 Public Network Components Network Media  Communication across a network is carried through a medium which allows a message to travel from source to destination.  Networks typically use three types of media: Metallic wires within cables, such as copper Glass, such as fiber optic cables Wireless transmission © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 13 Public Network Components Network Representations  Network diagrams, often called topology diagrams, use symbols to represent devices within the network.  In addition to the device representations on the right, it is important to remember and understand the following terms: Network Interface Card (NIC) Physical Port Interface © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 14 Public Network Components Topology Diagrams  Note the key differences between the two topology diagrams (physical location of devices vs. ports and network addressing schemes) © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 15 Public LANs and WANs Types of Networks  Two most common types of networks: Local Area Network (LAN) – spans a small geographic area owned or operated by an individual or IT department. Wide Area Network (WAN) – spans a large geographic area typically involving a telecommunications service provider. Other types of networks: Metropolitan Area Network (MAN) Wireless LAN (WLAN) Storage Area Network (SAN) © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 16 Public LANs and WANs Local Area Networks  Three characteristics of LANs: Spans a small geographic area such as a home, school, office building, or campus. Usually administered by a single organization or individual. Provides high speed bandwidth to end and intermediary devices within the network. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 17 Public LANs and WANs Wide Area Networks  Three characteristics of WANs: WANs interconnect LANs over wide geographical areas such as between cities, states, or countries. Usually administered by multiple service providers. WANs typically provide slower speed links between LANs. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 18 Public The Internet, Intranets, and Extranets The Internet  The Internet is a worldwide collection of interconnected LANs and WANs.  LANs are connected to each other using WANs.  WANs are then connected to each other using copper wires, fiber optic cables, and wireless transmissions.  The Internet is not owned by any individual or group, however, the following groups were developed to help maintain structure: IETF ICANN IAB © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 19 Public