The document provides an overview of local area networks (LANs), including common network topologies, components, and wireless LAN standards. It discusses LAN, WAN, CAN, and MAN network types and topologies like star, ring, and bus structures. Components like hubs, switches, routers, and access points are defined. Introduction to TCP/IP protocols includes definitions of IP and TCP. Finally, it covers IEEE 802.11 wireless LAN standards including 802.11, 802.11a, 802.11b, and 802.11g.
World Economic Forum : The Global Risks Report 2024
LAN and Network Topology Overview: Types, Components, Standards
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3. Network topology (# relevant for Ecolog-Net) -high wiring expenditure -net failure in case of failure or overloading of the hubs -simple cross-linking -simple extension -high reliability Star structure -complex error tracing -high wiring expenditure - when disturbances net failure -large net expansion Ring structure -net expansion limits -by cable interrupt the net precipitates -complicated access methods -easy to install -simply expandable -short cable lengths Bus structure Disadvantages Advantages Topology/structure
4. LAN – local area network Simple network: A simple network consists of at least two computers, which are connected by a direct connection (crossover cable) or with a Hub or Switch .
5. LAN – local area network Hub: A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. Switch: In networks, a device that filters and forwards packets between LAN segments.
6. LAN – local area network Network with Internet entrance and print server Router: A device that forwards data packets along networks. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP’s network (Internet Service Provider). Routers are located at gateways, the places where two or more networks connect.
7. LAN – local area network Radio network - Wireless LAN - WLAN Instead of cable-based connections; A simple Wireless LAN is a local network with an ACCESS POINT for WLAN adapter (network interface cards with antenna), which is attached to the computer or inserted.
8. LAN – local area network Access point: AP Short for Access Point , a hardware device or a computer's software that acts as a communication hub for users of a wireless device to connect to a wired LAN. APs are important for providing heightened wireless security and for extending the physical range of service a wireless user has access to. Network interface card: Often abbreviated as NIC , an expansion board you insert into a computer so the computer can be connected to a network. Most NICs are designed for a particular type of network, protocol, and media, although some can serve multiple networks.
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10. Introduction to TCP/IP IP: Abbreviation of I nternet P rotocol . IP specifies the format of packets, also called datagrams, and the addressing scheme. IP is responsible for moving packet of data from node to node (a processing location). IP forwards each packet based on a four byte destination address (the IP number).
11. Introduction to TCP/IP TCP: Abbreviation of Transmission Control Protocol . TCP is one of the main protocols in TCP/IP networks. Whereas the IP protocol deals only with packets, TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered in the same order in which they were sent. TCP - is responsible for verifying the correct delivery of data from client to server. Data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received.
12. IEEE-802.11 / Wireless LAN IEEE: Abbreviation of Institute of Electrical and Electronics Engineers. The IEEE is best known for developing standards for the computer and electronics industry. In particular, the IEEE 802 standards for local-area networks are widely followed. 802.11: 802.11 refers to a family of specifications developed by the IEEE for wireless LAN technology. 802.11 specifies an over-the-air interface between a wireless client and a base station or between two wireless clients.
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14. the datalogger company Joachim Gau ELPRO-BUCHS AG - Langäulistrasse 62 - CH-9471 Buchs SG – Switzerland Tel: +41 (0)81 750 03 11 - Fax.: +41 (0)81 750 03 17 Mail: swiss@elpro.com, ~ Internet: www.elpro.com,
Editor's Notes
Good morning to everyone. I first want to introduce myself: My name is Joachim Gau and I am in the sales department. I will give you in the next half hour a short overview about the network techniques. But it is really only a summary because we can’t become experts in half a hour. It could be useful to you, if you have already heard about some expressions: So first we want to see the types of networks and the network topology. What is LAN? An Introduction to TCP/IP and to IEEE-802.11
What is a network? Easy said: It is a group of computers and peripheral equipment which are linked together to use there common resources. (data’s, printer, fax, scanner, programs, modem and of course memory. The relevant type for the Ecolog-Net is the LAN
Network topology, that means the placing and the arrangement about computers and cables. They determine the hardware which can be used, as well as the access methods. These again have influence on transmission rate and the throughput of the data. The table is to give an overview of the pro and cons of the 3 basic topologies: The star structure is the relevant structure for our Ecolog-Net, also the today’s standard, It is very simple to add more computers or dataloggers, Main server at the ground floor or in the cellar, at each floor there is a router or a switch One disadvantage is the high wiring because for each node there must be a separate cable to the next switch. The company I worked before sells computer cable. More than 100 km in one buliding
Difference: the HUB copy the packets to the other ports, so that all segments of the LAN can see all packets! A SWITCH switches direct connections between the attached devices. So a switch is an intelligent HUB, who recognise over which port which device is connected.
Schnittstelle = interface between the wired LAN and the wireless LAN
IP by itself is something like the postal system. It allows you to address a package and drop it in the system, but there's no direct link between you and the recipient. TCP/IP, on the other hand, establishes a connection between two hosts so that they can send messages back and forth for a period of time.