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EGH208 IoMT Connectivity Technology Dr. Niu Jing (R.209, 65500767) The objective of this part Understand local area networks (LANS) Understand network topologies and access methods Recognize network devices and accessories Data Node Client Serv...

EGH208 IoMT Connectivity Technology Dr. Niu Jing (R.209, 65500767) The objective of this part Understand local area networks (LANS) Understand network topologies and access methods Recognize network devices and accessories Data Node Client Server Peer Network adapter Hub Switch Router Transport Media protocol Networks are used to exchange data Reasons for networks include Sharing information (eg. pictures, videos, documents…) Communication (eg. Email, WhatsApp…) Organizing data A Local Area Network (LAN) is a group of computers confined to a small geographic area, such as a single building A LAN is a group of computers or devise that share a common communication medium, such as cabled or wireless connections.  Hub A Hub is the most basic central connecting device Hubs enable computers on a network to communicate A host sends data to the hub. The hub sends the data to all devices connected to the hub Hubs cannot allow devices to send and receive data at the same time  Switch Switches work the same way as a hub, but they can identify (through MAC address) the intended recipient of the data. Switches allow devices to send and receive data at the same time.  Router Routers enable computers to communicate and allow communication between two networks - such as your home network and the internet. This communications link between the one network and the other is where the LAN ends.  Wireless Access Point The wireless access point (WAP) acts as the central connecting device for the network. It allows your wireless device to connect to the wired network. Wireless networks can consist of many types of devices other than traditional PCs: Smart phones Tablets PCs and laptops equipped with wireless network adapters And the smart Things  Network Adaptor and RJ45 Patch Cable A network adapter, also know as RJ45 (ethernet cable)- is a network interface card (NIC), is the type of network the hardware device enables you adapter connection to send and receive data from Transmit data in the form your computer. of electrical pulses  Serial Data Transfer Serial data transfer is the transfer of one bit at a time – transfer in a single-bit stream. On the network cable, data travels in a single bit stream. Data can travel in both directions-depends on type of connection  Data Transfer Rate Data transfer rate defines the maximum bits per second (bps) that can be transmitted over a network Rated in bits, and signified with a lowercase b (eg. 10Mbps) The lowercase b differentiates this unit from data that is stored on a hard drive, which uses an upper case B that stands for bytes (eg. 10MB)  IP address Computer and many other devices have an Internet Protocol (IP) address An IP address uniquely identifies your device and the associated network and allows each device to send and receive information A typical example of an IPv4 address would be 192.168.1.1 Every IP address is broken down into two parts by a subnet address Network ID 192.168.1 Host ID 1 Computers and other devices are connected using copper-based twisted-pair cables or wireless equipment A virtual LAN (VLAN) is a group of hosts with a common set of requirements that communicate as if they were connected together in a normal fashion on one switch, regardless of their physical location. A network topology defines the physical connections of hosts in a computer network There are several types of physical topologies including: Bus Star Ring Mesh Tree  Bus Topology All devices are connected via copper cable in a line  Star Topology Most common topology Each computer is individually wired to a central connecting device (hub, switch or SOHO router) Two star topologies can be connected via their central connecting devices to form a star-bus topology  Ring Topology In a LAN environment, each computer is connected to the network using a closed loop. Each device is connected to two other devices.  Mesh Topology Every computer connects to every other computer; no central connecting device is needed Setup is fault-tolerant: allows data to be sent via multiple pathways if one path fails Partial Mesh Full Mesh  Ethernet A standard that defines how data is sent and received between adapters, hubs, switches, and other network devices Most widely used standard on the internet today Standardized by the Institute of Electrical and Electronics Engineers (IEEE) as 802.3 802.3u or Fast ethernet that funs at 100Mbps 802.3ab or Gigabit Ethernet  IEEE 802.3 standard 802.3 Version Data Transfer Rate Cable Standard Cabling Used 802.3 10 Mbps 10BASE5 Thick coaxial 802.3a 10 Mbps 10BASE2 Thick coaxial 802.3i 10 Mbps 10BASE-T Twisted pair (TP) 802.3j 10 Mbps 10BASE-F Fiber optic 802.3u 100 Mbps 10BASE-TX TP using 2 pairs 100BASE-T4 TP using 4 pairs 100BASE-FX Fiber optics 802.3ab 1000 Mbps or 1000BASE-T Twisted pair 1 Gbps 802.3z 1000 Mbps or 1 Gbps 1000BASE-X Fiber optic 802.3ae 10 Gbps 10GBASE-SR, 10GBASE- Fiber optic LR,10GBASE-ER,and so on 802.3an 10Gbps 10BASE-T Twisted pair Computers on Ethernet networks communicate via frames A frame is a sequence of bits containing a detectable beginning and end of a packet in the stream of bits Include physical address information that helps switches determine where to send data Preamble crc (Frame check sequence) data Computing is done at a central location using terminals that are attached to this main system Mainframes are a powerful computer and the rest of the devices connected to the computer are known as terminals (or dumb terminals). Each terminal consisted solely of a keyboard and display with no processing power Dumb Dumb Client B Client C Mainframe Dumb Computer/Server Dumb Client A Client D Peers are both service providers and service requestors Peer-to-peer networking distributes application or workloads between computers The client/server model is an architecture that distributes applications between servers and client computers Server: System that provides services such as Windows Server 2016 Client: Device that requests services such as Windows 10 More powerful computers that provide centralized services: File Print Database Network controller Messaging/Email Web In a distributed computing system, multiple client computers work together to solve a task. Every device or workstation has its own processing power It is scalable and offer no single point of failure. P2P can also refer to file sharing networks Examples of file sharing networks Napster Gnutella G2 Other technologies also take advantage of P2P file sharing Skype VoIP