Network topology is the study of the arrangement or mapping of the elements (links, nodes, etc.) of a network, especially the physical (real) and logical (virtual) interconnections between nodes..
Defines the way in which computers, printers, and other devices are connected, physically and logically. A network topology describes the layout of the wire and devices as well as the paths used by data transmissions.
2.Examples of Network Topology, their Definition and post example picture.
Star topology
Also known as a star network, a star topology is one of the most common network setups where each of the devices and computers on a network connect to a central hub. A major disadvantage of this type of network topology is that if the central hub fails, all computers connected to that hub would be disconnected. Below is a visual example of a simple computer setup on a network using the star topology.
Ring topology
Also known as a ring network, the ring topology is a type of computer network configuration where each network computer and device are connected to each other forming a large circle (or similar shape). Each packet is sent around the ring until it reaches its final destination. Today, the ring topology is seldom used. Below is a visual example of a simple computer setup on a network using a ring topology.
Mesh topology
The value of fully meshed networks is proportional to the exponent of the number of subscribers, assuming that communicating groups of any two endpoints, up to and including all the endpoints, is approximated by Reed's Law.2 kinds of mesh topology:
A. FULLY CONNECTED NETWORK
A fully connected network is a mesh network in which each of the nodes is connected to each other. A fully connected network doesn't need to use switching nor broadcasting. However, its major disadvantage is that the number of connections grows quadratically with the number of nodes, per formula
and so it is extremely impractical for large networks. A two-node network, one of the most common network types, is technically a fully connected network.
The type of network topology in which some of the nodes of the network are connected to more than one other node in the network with a point-to-point link – this makes it possible to take advantage of some of the redundancy that is provided by a physical fully connected mesh topology without the expense and complexity required for a connection between every node in the network.
Bus topology
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Tree topology
Also known as a star bus topology, tree topology is one of the most common types of network setups that is similar to a bus topology and a star topology. A tree topology connects multiple star networks to other star networks. Below is a visual example of a simple computer setup on a network using the star topology.
3.What is OSI Layer?
Short for Open System Interconnection, OSI is a network model developed by ISO in 1978 where peer-to-peer communications are divided into seven layers. Each layer performs a specific task or tasks, and builds upon the preceding layer until the communications are complete. Below are the purposes of each of the seven layers.
4. Examples of OSI Layer, their definition in order.
1 - Physical layer - responsible for the electrical, mechanical and timing across the link.
2 - Data link layer (also known as the link layer) - responsible for transmitting data across a link.
3 - Network layer - responsible for routing information through the network and allowing systems to communicate.
4 - Transport layer - responsible for transferring information between endpoints on the network and deals with errors such as lost or duplicate packets.
5 - Session layer - responsible for managing a session between two applications.
6 - Presentation layer - responsible for the data formatting and display, allowing for compatibility.
7 - Application layer - responsible for user interaction. An example of an OSI application is the FTAM.5. What is Networking?
NETWORKING-Is a group of computers that are connected to each other for the purpose of communication. Networks may be classified according to a wide variety of characteristics. This article provides a general overview of types and categories and also presents the basic components of a network.
6. Example of Networking, Post at least 5 examples with picture.
Local area network
A local area network (LAN) is a network that connects computers and devices in a limited geographical area such as home, school, computer laboratory, office building, or closely positioned group of buildings. Each computer or device on the network is a node. Current wired LANs are most likely to be based on Ethernet technology, although new standards like ITU-T G.hn also provide a way to create a wired LAN using existing home wires (coaxial cables, phone lines and power lines)
Home area network
A home area network (HAN) or home hetwork is a residential local area network. It is used for communication between digital devices typically deployed in the home, usually a small number of personal computers and accessories, such as printers and mobile computing devices. An important function is the sharing of Internet access, often a broadband service through a CATV or Digital Subscriber Line (DSL) provider.
Storage area network
A storage area network is an network architecture to attach remote computer storage devices (such as disk arrays, tape libraries, and optical jukeboxes) to servers in such a way that the devices appear as locally attached to the operating system. A SAN typically is its own network of storage devices that are generally not accessible through the regular network by regular devices. The cost and complexity of SANs has dropped in recent years, resulting in much wider adoption across both enterprise and small to medium sized business environments.
Campus area network
A campus area network (CAN) is a computer network made up of an interconnection of local area networks (LANs) within a limited geographical area. It can be considered one form of a metropolitan area network, specific to an academic setting.
In the case of a university campus-based campus area network, the network is likely to link a variety of campus buildings including; academic departments, the university library and student residence halls. A campus area network is larger than a local area network but smaller than a wide area network (WAN) (in some cases).\
Metropolitan area network
A metropolitan area network (MAN) is a network that connects two or more local area networks or campus area networks together but does not extend beyond the boundaries of the immediate town/city. Routers, switches and hubs are connected to create a metropolitan area network.
NIC Cards
The Network Interface Card (NIC) is a circuit board that is physically installed within an active network node, such as a computer, server, or printer. The NIC is an adapter that controls the exchange of information between the network and the user. Newer NICs are increasingly pre-installed and have the ability to automatically configure to match the speed of the network to which they are connected. For example, if a workstation is attached to a switch on a dedicated connection, the adapter may configure itself to run full-duplex (both talking and listening at the same time) without fear of collisions.
Network repeaters regenerate incoming electrical, wireless or optical signals. With physical media like Ethernet or Wi-Fi(wireless media), data transmissions can only span a limited distance before the quality of the signal degrades. Repeaters attempt to preserve signal integrity and extend the distance over which data can safely travel.
| Cable/DSL |
Typically DSL and Cable Modems connect to the carrier on one side and a modem on the other. Essentially you must discover the type of system your school uses to decide how to hook-up from there. This is the only type of system going into the home and thus will be of interest to you for that reason. The cable and the DSL lines are probably going to be 10Megabit since that is faster than any of the providers of this service are at this time.
The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed.
| Firewalls |
Basic security to control the flow of data in and out of a network. For our purposes this is controlled by the server that brings all connectivity to computers outside of the classroom. If this were a home cable or DSL line then you would want to install a firewall (software) that would control what other people on the internet can see in your personal computer.
Hubs
A hub is a small, simple network device that allows multiple connected computers to communicate. A hub may contain multiple ports that can connect a group of computers in a peer-to-peer fashion, accepting and repeating signals from each node. A slightly more sophisticated hub may contain multiple ports for devices and one port that connects to a network’s backbone. On Ethernet networks, hubs typically serve as the central connection point for branches of a star or star-based hybrid topology.
Switches
A network switch is a small hardware device that joins multiple computers together within one local area network (LAN). Technically, network switches operate at layer two (Data Link Layer) of the OSI model.
Bridges
A bridge device filters data traffic at a network boundary.Bridges have a single input and a single output port.They differ from repeaters in that they can interpret the data they retransmit.
Gateways
A network gateway is an internetworking system, a system that joins two networks together. A network gateway can be implemented completely in software, completely in hardware, or as a combination of the two. Depending on their implementation, network gateways can operate at any level of the OSI model from application protocols to low-level signaling.
Routers
A router is a multiport connectivity device that can integrate LANs and WANs running at different transmission speeds and using a variety of protocols. Routers operate at the Network layer (Layer 3) of the OSI Model. Routers have been slower than switches or bridges because they pay attention to information in Layers 3 and higher, such as protocols and logical addresses. Consequently, unlike bridges and Layer 2 switches, routers are protocol-dependent.They must be designed or configured to recognize a certain protocol before they can forward data transmitted using that protocol.
8. Example of networking cables and their functions, post at least 10 w/ picture.
Patch cable-
A patch cable is an electrical or optical cable, used to connect one electronic or optical device to another for signal routing. Devices of different types (ie: a switch connected to a computer, or switch to router) are connected with patch cords. It is a very fast connection speed. Patch cords are usually produced in many different colors so as to be easily distinguishable[2], and are relatively short, perhaps no longer than two Ethernet crossover cable.
Ethernet crossover cable
is a type of Ethernet cable used to connect computing devices together directly where they would normally be connected via a network switch, hub or router, such as directly connecting two personal computers via their network adapters.
Power lines
Although power wires are not designed for networking applications, new technologies like Power line communication allows these wires to also be used to interconnect home computers, peripherals or other networked consumer products. On December 2008, the ITU-T adopted Recommendation G.hn/G.9960 as the first worldwide standard for high-speed powerline communications also specifies communications over phonelines and coaxial wiring.
Plenum cable
is cable that is laid in the plenum spaces of buildings. The plenum (pronounced /ˈplɛnəm/) is the space that can facilitate air circulation for heating and air conditioning systems, by providing pathways for either heated/conditioned or return airflows. Space between the structural ceiling and the dropped ceiling or under a raised floor is typically considered plenum; however, some drop ceiling designs create a tight seal that does not allow for airflow and therefore may not be considered a plenum air-handling space.
Audio multi-core cable
A multicore cable "snake" helps sound engineers to route a number of signals without having to have a tangled mess of individual cables
Used in the audio recording and sound reinforcement fields, an audio multicore cable (most commonly known as a snake cable or just a snake) is a compact cable, typically about the diameter of a coin, which contains from 4 to 56 individual shielded pair microphone cables all housed by one rugged, heavy-duty common outer jacket. Each end of the multicore cable terminates in a "tail", which contains either a patchbay for female XLR or 1/4" jacks or male plugs.
Twisted pair cabling-is a type of wiring in which two conductors (the forward and
return conductors of a single circuit) are twisted together for the purposes of canceling
out electromagnetic interference (EMI) from external sources; for instance,
electromagnetic radiation from Unshielded Twisted Pair (UTP) cables, and crosstalk
between neighboring pairs.
Coaxial cable-or coax, is an electrical cable with an inner conductor surrounded by a
tubular insulating layer typically of a flexible material with a high dielectric constant,
all of which are surrounded by a conductive layer called the shield (typically of fine
woven wire for flexibility, or of a thin metallic foil), and finally covered with a thin
insulating layer on the outside. The term coaxial comes from the inner conductor and the
outer shield sharing the same geometric axis.
Fiber-optic-communication is a method of transmitting information from one place to
another by sending pulses of light through an optical fiber. The light forms an
electromagnetic carrier wave that is modulated to carry information. First developed
in the 1970s, fiber-optic communication systems have revolutionized the telecommunications
industry and have played a major role in the advent of the Information Age. Because of its
advantages over electrical transmission, optical fibers have largely replaced copper wire
communications in core networks in the developed world.
Unshielded Twisted Pair (UTP)
UTP cable is a medium that is composed of pairs of wires (see Figure 8-1). UTP cable is used in a variety of networks. Each of the eight individual copper wires in UTP cable \is covered by an insulating material. In addition, the wires in each pair are twisted around each other. UTP cable relies solely on the cancellation effect produced by the twisted wire pairs to limit signal degradation caused by electromagnetic interference (EMI) and radio frequency interference (RFI). To further reduce crosstalk between the pairs in UTP cable, the number of twists in the wire pairs varies. UTP cable must follow precise specifications governing how many twists or braids are permitted per meter (3.28 feet) of cable.
Shielded Twisted-Pair Cable
Shielded twisted-pair (STP) cable combines the techniques of shielding, cancellation, and wire twisting. Each pair of wires is wrapped in a metallic foil. The four pairs of wires then are wrapped in an overall metallic braid or foil, usually 150-ohm cable. As specified for use in Ethernet network installations, STP reduces electrical noise both within the cable (pair-to-pair coupling, or crosstalk) and from outside the cable (EMI and RFI). STP usually is installed with STP data connector, which is created especially for the STP cable. However, STP cabling also can use the same RJ connectors that UTP uses.
