mcq network .pdf

Networking Technologi es Hansika Mahaadikara Senior Lecturer - FoC Ms. Hansika Mahaadikara Faculty of Computing Department of CSE ICT in The Society Data Communicatio n Smart Devices Smart vehicles Smart Homes Information Security Mobile Communicatio n Module Objectives Module Title: Ne...

Networking Technologi es Hansika Mahaadikara Senior Lecturer - FoC Ms. Hansika Mahaadikara Faculty of Computing Department of CSE ICT in The Society Data Communicatio n Smart Devices Smart vehicles Smart Homes Information Security Mobile Communicatio n Module Objectives Module Title: Networking Today Module Objective: Explain the advances in modern technologies. Topic Title Topic Objective Networks Affect our Lives Explain how networks affect our daily lives. Network Components Explain how host and network devices are used. Network Representations and Explain network representations and how they are used in network topologies. Topologies Common Types of Networks Compare the characteristics of common types of networks. Internet Connections Explain how LANs and WANs interconnect to the internet. Reliable Networks Describe the four basic requirements of a reliable network. Network Trends Explain how trends such as BYOD, online collaboration, video, and cloud computing are changing the way we interact. Network Security Identify some basic security threats and solution for all networks. The IT Professional Explain employment opportunities in the networking field. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 10 1.1 Networks Affect Our Lives © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 11 Networking Today Networks Connect Us Communication is almost as important to us as our reliance on air, water, food, and shelter. In today’s world, through the use of networks, all devices are connected like never before. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 12 Networking Today No Boundaries World without boundaries Global communities Human network © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 13 1.2 Network Components © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 14 Network Components Host Roles Every computer on a network is called a host or end device. Servers are computers that provide information to end devices: email servers web servers Server Description file server Type Clients are computers that send Email Email server runs email server software. requests to the servers to retrieve Clients use client software to access email. information: Web Web server runs web server software. Clients use browser software to access web pages. web page from a web server email from an email server File File server stores corporate and user files. The client devices access these files. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 15 Network Components Peer-to-Peer It is possible to have a device be a client and a server in a Peer-to-Peer Network. This type of network design is only recommended for very small networks. Advantages Disadvantages Easy to set up No centralized administration Less complex Not as secure Lower cost Not scalable Used for simple tasks: transferring files Slower performance and sharing printers © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 16 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 17 Network Components Intermediary Network Devices An intermediary device interconnects end devices. Examples include switches, wireless access points, routers, and firewalls. 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 in the network. Notify other devices of errors and communication failures. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 18 Network Components Network Media Communication across a network is carried through a medium which allows a message to travel from source to destination. Media Types Description Metal wires within Uses electrical impulses cables Glass or plastic fibers Uses pulses of light. within cables (fiber- optic cable) Wireless transmission Uses modulation of specific frequencies of electromagnetic waves. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 19 1.3 Network Representations and Topologies © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 20 Network Representations and Topologies Network Representations Network diagrams, often called topology diagrams, use symbols to represent devices within the network. Important terms to know include: Network Interface Card (NIC) Physical Port Interface Note: Often, the terms port and interface are used interchangeably © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 21 Network Representations and Topologies Topology Diagrams Physical topology diagrams illustrate the Logical topology diagrams illustrate devices, physical location of intermediary devices and ports, and the addressing scheme of the cable installation. network. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 22 1.4 Common Types of Networks © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 23 Common Types of Networks 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 Small Home SOHO 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 Medium/Large World Wide © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 24 Common Types of Networks LANs and WANs Network infrastructures vary greatly in terms of: Size of the area covered Number of users connected Number and types of services available Area of responsibility Two most common types of networks: Local Area Network (LAN) Wide Area Network (WAN). © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 25 Common Types of Networks LANs and WANs (cont.) A LAN is a network infrastructure that spans A WAN is a network infrastructure that spans a small geographical area. a wide geographical area. LAN WAN Interconnect end devices in a limited area. Interconnect LANs over wide geographical areas. Administered by a single organization or Typically administered by one or more service individual. providers. Provide high-speed bandwidth to internal Typically provide slower speed links between LANs. devices. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 26 Common Types of Networks The Internet The internet is a worldwide collection of interconnected LANs and WANs. LANs are connected to each other using WANs. WANs may use copper wires, fiber optic cables, and wireless transmissions. The internet is not owned by any individual or group. The following groups were developed to help maintain structure on the internet: IETF ICANN IAB © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 27 Common Types of Networks Intranets and Extranets An intranet is a private collection of LANs and WANs internal to an organization that is meant to be accessible only to the organizations members or others with authorization. An organization might use an extranet to provide secure access to their network for individuals who work for a different organization that need access to their data on their network. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 28 1.5 Internet Connections © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 29 Internet Connections Internet Access Technologies There are many ways to connect users and organizations to the internet: Popular services for home users and small offices include broadband cable, broadband digital subscriber line (DSL), wireless WANs, and mobile services. Organizations need faster connections to support IP phones, video conferencing and data center storage. Business-class interconnections are usually provided by service providers (SP) and may include: business DSL, leased lines, and Metro Ethernet. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 30 Internet Connections Home and Small Office Internet Connections Connection Description Cable high bandwidth, always on, internet offered by cable television service providers. DSL high bandwidth, always on, internet connection that runs over a telephone line. Cellular uses a cell phone network to connect to the internet. Satellite major benefit to rural areas without Internet Service Providers. Dial-up an inexpensive, low bandwidth telephone option using a modem. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 31 Internet Connections Businesses Internet Connections Corporate business connections may Type of Description require: Connection Dedicated These are reserved circuits within the higher bandwidth Leased Line service provider’s network that connect dedicated connections distant offices with private voice and/or data networking. managed services Ethernet This extends LAN access technology into WAN the WAN. DSL Business DSL is available in various formats including Symmetric Digital Subscriber Lines (SDSL). Satellite This can provide a connection when a wired solution is not available. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 32 Internet Connections The Converging Network Before converged networks, an organization would have been separately cabled for telephone, video, and data. Each of these networks would use different technologies to carry the signal. Each of these technologies would use a different set of rules and standards. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 33 Internet Connections The Converging Network (Cont.) Converged data networks carry multiple services on one link including: data voice video Converged networks can deliver data, voice, and video over the same network infrastructure. The network infrastructure uses the same set of rules and standards. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 34 1.6 Reliable Networks © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 35 Reliable Network Network Architecture Network Architecture refers to the technologies that support the infrastructure that moves data across the network. There are four basic characteristics that the underlying architectures need to address to meet user expectations: Fault Tolerance Scalability Quality of Service (QoS) Security © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 36 Reliable Network Fault Tolerance A fault tolerant network limits the impact of a failure by limiting the number of affected devices. Multiple paths are required for fault tolerance. Reliable networks provide redundancy by implementing a packet switched network: Packet switching splits traffic into packets that are routed over a network. Each packet could theoretically take a different path to the destination. This is not possible with circuit-switched networks which establish dedicated circuits. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 37 Reliable Network Scalability A scalable network can expand quickly and easily to support new users and applications without impacting the performance of services to existing users. Network designers follow accepted standards and protocols in order to make the networks scalable. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 38  Reliable Network Quality of Service Voice and live video transmissions require higher expectations for those services being delivered. Have you ever watched a live video with constant breaks and pauses? This is caused when there is a higher demand for bandwidth than available – and QoS isn’t configured. Quality of Service (QoS) is the primary mechanism used to ensure reliable delivery of content for all users. With a QoS policy in place, the router can more easily manage the flow of data and voice traffic. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 39 Reliable Network There are two main types of network Network Security security that must be addressed: Network infrastructure security Physical security of network devices Preventing unauthorized access to the devices Information Security Protection of the information or data transmitted over the network Three goals of network security: Confidentiality – only intended recipients can read the data Integrity – assurance that the data has not be altered with during transmission Availability – assurance of timely and reliable access to data for authorized users © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 40 1.7 Network Trends © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 41 Network Trends Recent Trends The role of the network must adjust and continually transform in order to be able to keep up with new technologies and end user devices as they constantly come to the market. Several new networking trends that effect organizations and consumers: Bring Your Own Device (BYOD) Online collaboration Video communications Cloud computing © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 42 Network Trends Bring Your Own Device (BYOD) allows Bring Your Own Device users to use their own devices giving them more opportunities and greater flexibility. BYOD allows end users to have the freedom to use personal tools to access information and communicate using their: Laptops Netbooks Tablets Smartphones E-readers BYOD means any device, with any ownership, used anywhere. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 43 Network Trends Cloud Computing Cloud computing allows us to store personal files or backup our data on servers over the internet. Applications can also be accessed using the Cloud. Allows businesses to deliver to any device anywhere in the world. Cloud computing is made possible by data centers. Smaller companies that can’t afford their own data centers, lease server and storage services from larger data center organizations in the Cloud. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 44 Network Trends Technology Trends in the Home Smart home technology is a growing trend that allows technology to be integrated into every-day appliances which allows them to interconnect with other devices. Ovens might know what time to cook a meal for you by communicating with your calendar on what time you are scheduled to be home. Smart home technology is currently being developed for all rooms within a house. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 45 Network Trends Powerline networking can Powerline Networking allow devices to connect to a LAN where data network cables or wireless communications are not a viable option. Using a standard powerline adapter, devices can connect to the LAN wherever there is an electrical outlet by sending data on certain frequencies. Powerline networking is especially useful when wireless access points cannot reach all the devices in the home. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 46 Network Trends Wireless Broadband In addition to DSL and cable, wireless is another option used to connect homes and small businesses to the internet. More commonly found in rural environments, a Wireless Internet Service Provider (WISP) is an ISP that connects subscribers to designated access points or hotspots. Wireless broadband is another solution for the home and small businesses. Uses the same cellular technology used by a smart phone. An antenna is installed outside the house providing wireless or wired connectivity for devices in the home. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 47 1.8 Network Security © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 48 Network Security Security Threats Network security is an integral part of networking regardless of the size of the network. The network security that is implemented must take into account the environment while securing the data, but still allowing for quality of service that is expected of the network. Securing a network involves many protocols, technologies, devices, tools, and techniques in order to secure data and mitigate threats. Threat vectors might be external or internal. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 49 Network Security External Threats: Security Threats (Cont.) Viruses, worms, and Trojan horses Spyware and adware Zero-day attacks Threat Actor attacks Denial of service attacks Data interception and theft Identity theft Internal Threats: lost or stolen devices accidental misuse by employees malicious employees © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 50 Network Security Security Solutions Security must be implemented in multiple layers using more than one security solution. Network security components for home or small office network: Antivirus and antispyware software should be installed on end devices. Firewall filtering used to block unauthorized access to the network. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 51 Network Security Security Solutions (Cont.) Larger networks have additional security requirements: Dedicated firewall system Access control lists (ACL) Intrusion prevention systems (IPS) Virtual private networks (VPN) The study of network security starts with a clear understanding of the underlying switching and routing infrastructure. © 2016 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 52