Week 01 - Basic Concepts 2024 PDF

Week 01: Basic Concepts Learning Goals: By the end of class you should be able to… List the 5 components of data communication Distinguish between simplex, half duplex, and full duplex Define a network and identify some of the key componen...

Week 01: Basic Concepts Learning Goals: By the end of class you should be able to… List the 5 components of data communication Distinguish between simplex, half duplex, and full duplex Define a network and identify some of the key components of a network Define LAN, WAN, MAN, PAN Identify mesh, star, ring, hybrid topologies and advantages/disadvantages of each Distinguish between point to point and point to multipoint Distinguish between packet switched and network switch networks Identify major standardizations bodies (ANSI, IEEE, etc…)  Data Flow Simplex (computer monitor) Half-duplex (walkie talkie) Full-duplex ( telephone)  What are the necessary components of communication?  Components of Data Communication 5 Components of Data Communication 1. Sender 2. Receiver 3. Message 4. Transmission media 5. Protocol  Network A network is the interconnection of a set of devices capable of communication Made up of: – Nodes – Links – Interfaces  Network: Nodes Nodes – End nodes: PC, servers, smart phones – Connecting (networking) nodes: Modems, Switches, Access Points, Routers  Features of Network Network criteria – Performance Throughput Delay – Reliability – Security Physical structure Physical Topology Types of Connection Network Types  Network Types What is the difference between each of the following? – Local Area Network (LAN) – Wide Area Network (WAN) – Metropolitan Area Network (MAN) – Personal Area Network (PAN)  LAN A Local Area Network (LAN) is usually privately owned and connects some hosts in a single office, building, or campus Depending on the needs of an organization, – A LAN can be as simple as two PCs and a printer in someone’s home office, or – It can extend throughout a company and include audio and video devices  LAN Each host in a LAN has an identifier, an address, that uniquely defines the host in the LAN A packet sent by a host to another host carries both the source host’s and the destination host’s addresses  Comparison Table LAN MAN WAN PAN 1. LAN stands for Local 1. MAN stands for 1. WAN stands for 1. PAN stands for Area Network. Metropolitan Area Wide Area Network. Personal Area Network. Network 2. Limited in Size 2. A MAN is optimized 2. Its long distance 2. Covers small for a large geographical communications. distances area than LAN. (usually a Usually wider than a usually a room few blocks) MAN (ambiguous) (Bluetooth, e.g. The Internet USB) 3. Privately owned and 3. Owned by businesses operated leased by customers 4. Point to point or 4. Usually only point to point to multipoint point 5. Connects host like 5. Usually connects PCs and Servers networking devices like switches and routers  WAN Links Point-to-point WAN link Switched WAN  A Practical Examples of Interconnection An internetwork made of two LANs and one WAN Heterogeneous Network Made of WANs and LANs  Point to Point/ Point to Multi-point Connections Examples of each? Point to Point  Multipoint Multipoint (point-to-multipoint) link, shared links Network Topology  Physical Topology Physical Topology refers to the way in which a network is laid out physically Four basic topologies – Mesh – Star – Bus – Ring  Mesh Topology Full mesh – Each node is connected to every other node – Very reliable, but – Quite expensive If there are n nodes in the network, we need: (i) n(n-1)/2 links (ii) n(n-1) interfaces n=5 Partial mesh # of links = # of interfaces =  Star Topology Each end node is connected to a central controller (hub) node with – Point-to-point links – No connection between end nodes  Bus Topology Each end-node is connected to – A backbone cable – Using multipoint links Not used in modern networks  Ring Topology Networking nodes daisy-chained connection using – Point-to-point link End nodes are connected to networking nodes get the data on the ring Used in Optical Fibre network in WANs  Hybrid Topology Combination of more than one basic topology More practical Hybrid topology is always an extended star  Switching An internet is a switched network in which a switch connects at least two links together A switch needs to forward data from a network to another network when required The two most common types of switched networks are: – Circuit-Switched (CS) network – Packet Switched (PS) network  Difference between Circuit and Packet Switched Network Circuit switch maintain a connection, all data follows the same path throughout the communication (can waste bandwidth – even if no data being sent there is an established connection) - telephone call Packet switching data can follow any path it wants to go from source to destination (field trip to the CN tower) Circuit-Switched (CS) Network Packet-Switched (PS) Network Networking Standards Standardization Bodies  Internet Standards An Internet standard is a thoroughly tested specification that is useful to and adhered to by those who work with the Internet – It is a formalized regulation that must be followed Internet Engineering Task Force (IETF) makes the internet standard, and they are one of two sub- organizations of the Internet Society Internet draft – Initial document RFC- Request for Comment – Working protocols are already there Standard – Formal ‘Standard’ status Internet Internet RFC Draft Standard  Standardization Bodies International – International Organization for Standardization (ISO) – International Telecommunication Union (ITU) – International Electrotechnical Commission (IEC) – … Regional – ETSI (Europe) Country – Standards Council of Canada (SCC) – American National Standards Institute (ANSI) Other – IEEE, IETF, W3C  ISO International Organization for Standardization Collection of organization standards representing 146+ countries Goal is to establish international technological standards to facilitate global exchange of information and barrier-free trade Fewer than 300 of ISO’s more than 14,250 standards apply to computer-related products and functions Most famous for developing the Open Standard Interconnect Model (OSI)  ITU International Telecommunication Union Regulates international telecommunications: – Radio and TV frequencies – Satellite and telephony specifications – Networking infrastructure – Tariffs applied to global communications Typically, documents pertain more to global telecommunications issues than to industry technical specifications  IEEE Institute of Electrical and Electronics Engineers International society composed of engineering professionals Goals are to promote development and education in electrical engineering and computer science IEEE technical papers and standards (Project 802) are highly respected in the networking profession – Can purchase IEEE documents online from IEEE’s Web site (www.ieee.org)  Standards Council of Canada (SCC) Federal Crown corporation Promote efficient and effective voluntary standardization in Canada, where standardization is not expressly provided for by law Does not develop standards directly – Helps other organizations to develop or participate in international standards Represents Canada in international standardization – E.g in ISO and IEC Web: http://www.scc.ca/  ANSI American National Standards Institute (ANSI) – Composed of more than a thousand representatives from industry and government – Represents United States in setting international standards ANSI standards documents available: – ANSI’s Web site (www.ansi.org) – At university or public libraries  EIA and TIA Electronic Industries Alliance (EIA): – Trade organization composed of representatives from electronics manufacturing firms across US – Sets standards for its members – Helps write ANSI standards – Lobbies for legislation favorable to growth of computer and electronics industries Telecommunications Industry Association (TIA): – Focuses on standards for information technology (IT), wireless, satellite, fiber optics, and telephone equipment  ISOC Internet Society Professional membership society that helps to establish technical standards for the Internet Oversees groups with specific missions: – Internet Architecture Board (IAB): Technical advisory group of researchers and professionals Interested in overseeing Internet’s design and management – Internet Engineering Task Force (IETF): Sets standards for how systems communicate over the Internet How protocols operate and interact  IANA and ICANN Internet Protocol (IP) addresses – Addresses used to identify computers on the Internet and other TCP/IP-based networks Internet Assigned Numbers Authority (IANA): Used to keep records of available and reserved IP addresses – In 1997, coordinated efforts with three Regional Internet Registries (RIRs) Not-for-profit agency that manages distribution of IP addresses to private and public entities – In late 1990s U.S. Department of Commerce (DOC) overhauled IP addressing and domain name management Internet Corporation for Assigned Names and Numbers (ICANN): Ultimately responsible for IP addressing and domain name management – IANA still performs system administration – Individuals and businesses lease addresses from Internet Service Provider (ISP) Business providing access to Internet and other services  World Wide Web Consortium (W3C) Develop web related standards World-wide membership and offices Main standards – HTML – CSS – XML – DOM