Introduction
In the OSI model of computer networking, the data link layer is layer two of seven and corresponds to the host-to-network layer of the TCP/IP reference model. Its main aim is to reliably transfer data between two adjacent machines whilst efficiently detecting and correcting errors in transmission. Packets from the network layer are packed into frames and transferred to the network layer on another machine. Data link layer protocols respond to the network layer and issue requests to the physical layer. The data link layer in LANs can contain Media Access Control and Logical Link Control sub-layers.
Unacknowledged connectionless service can be offered by the data link layer. It is used in LANs and other reliable mediums or real-time traffic situations. No connection is established when the source machine sends individual frames to a machine, frames are not acknowledged.
Acknowledged connectionless service works on the same principles as unacknowledged connectionless service except each individual frame is acknowledged on reception. It is used on unreliable media such as wireless.
Acknowledged connection-oriented service is also provided by the data link layer, data is sent and acknowledged. The data link establishes a connection to send data then releases it once the data has been successfully sent.
Framing
In order to transfer data between layers, a bitstream is split into frames containing the frames source and destination information. Errors can occur during transmission of frames which are rectified using a suitable protocol. Frames are transferred between LAN devices by the data link layer. A frame contains a header which includes the source and destination address of the frame. Frames are delivered using...
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...evel messages into frames. Sent data needs to be checked for errors when using some protocols and the data link layer monitors and corrects errors that occur on lower levels of the network.
Works Cited
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Multiplexing will gather the data from the source host and give that data some header information. This data will be created into segments by demultiplexing and then be sent to the 3rd layer (Network layer). So to summarize multiplexing will gather data and give it header information and demultiplexing will create segments and sent them to the network layer. Now with flow control that will relate with multiplexing, mainly because it can take multiple data streams and combine them into one shared stream, making that a form of data flow control. Now as far as error checking that will relate to the frames of the data. The logical link control will use a frame check sequence (FCS) to check the frame to see if there is any problems with it. If it detects an error during the frame check sequence then the frame will be discarded and the data will be passed on to the network layer. With this all being said this will mainly be used in the OSI model since the logical link control is the sub-layer for the data link layer. (The other sub layer being MAC) Without the logical link control or 802.2 then the data link layer wouldn’t function
MAC Layer Connections: Management connections and data transport connections are two connections in this layer. The management connections have three types: basic, primary, and secondary. A basic connection and primary connection are created for each MS when they join the network. A basic connection is used for short and urgent management message. And a primary connection is used for delay-tolerant management messages. The secondary connection is used for IP summarized management messages such as dynamic host configuration protocol [DHCP], and simple network management protocol [SNMP]. Transport connections can be provisioned or can be recognized on demand. They are used for user traffic flows. Unicast or multicast can be used for transmission.
It also provide MAC addresses. Every MAC address is unique and it belongs to that particular device. The data link layer is responsible for the means to send out data over the physical layer (Tetz, 2011). Without the data link layer of the OSI devices would not have this unique address that identifies them, as well as not having a means to send out data of the physical layer. The Physical and Data Link layer walk hand in hand in the OSI Model and cannot work without the other.
Last phase is data exchange. In data exchange, client and server exchanges the data by creating one or more data channels. In each channel, flow is control using window space available. There are 3 stages of the life of the channel: open channel, data transfer and close channel. One the channel is open by either of the party, data is transferred and then channel is closed by either of the party [3].
Sending data through the internet efficiently has always posed many problems. The two major technologies used, Ethernet and Asynchronous Transfer Mode (ATM), have done an admirable job of porting data, voice and video from one point to another. However, they both fall short in differing areas; neither has been able to present the "complete" package to become the single, dominant player in the internet market. They both have dominant areas they cover. Ethernet has dominated the LAN side, while ATM covers the WAN (backbone). This paper will compare the two technologies and determine which has a hand-up in the data trafficking world.
TCP/IP is a network model which enables the communication across the Internet. The most fundamental protocol on which the Internet is built. This is made up of the 2 common networking protocols, TCP, for Transmission Control Protocol, and IP, for Internet Protocol. TCP maintains and handles packet flow linking the systems and IP protocol has the ability to handle the routing of packets. However The TCP/IP stack consists of 5 layers first being application layer, the transport layer, then the network layer, the link layer and finally the physical layer. The assignment focuses on the three middle layers and is divided into five parts. Firstly explaining how the TCP and UDP the most vital protocols needed to deliver and communicate.
LAN is used to share resources such as files, printers, games and other application between clients and also...
Local Area Networks also called LANs have been a major player in industrialization of computers. In the past 20 or so years the worlds industry has be invaded with new computer technology. It has made such an impact on the way we do business that it has become essential with an ever-growing need for improvement. LANs give an employer the ability to share information between computers with a simple relatively inexpensive system of network cards and software. It also lets the user or users share hardware such as Printers and scanners. The speed of access between the computers is lighting fast because the data has a short distance to cover. In most cases a LAN only occupies one or a group of buildings located next to each other. For larger area need there are several other types of networks such as the Internet.
One of the most basic types of topologies is Point to Point, where a connection between two nodes is established just to communicate between the two. One of most basic examples of this is a two tin can’s on a string; they are connected to each other just so the two can communicate. This relationship can also be observed with two computers connected with a crossover Ethernet cord. This method of connection is also used for communication through telephone, but this is achieved logically. Switched telecommunications systems are used to create a link between two phones to connect them and allow communications between the two and then dropped when the connection is no longer needed. Point to Point communication in modern times is still prevalent, but achieved using more complex networks with the help of logical networking, and can be used to describe many of the connections between individual parts of a network.
A local Area Network (LAN) is a type of network typically used and connected in a small area, for instance, home, office, school or groups of building, in order to communicate with one another and share resource, such as printer or scanner. Those devices could be connected between each other by wired cable or wireless links, which is typically used as a standard LAN technology called IEEE 802.11. Usually, a local area network consists of computers and peripheral devices connected to a local domain server, which are used to share printers and other resources, such as disk storage, games or applications. Each LAN is either independent from any network or connects to other LANs, and, moreover, can additionally connect to Internet called Wide Area Network (WAN). In terms of practical use, a home network is typically individual LANs and multiple LANs, which refers to a home network setting up a guest network. In this paper, I will expound the main components making up a local area network (LAN), as well as technologies used to build a LAN.
Synchronization: The receiver is able to determine when a signal begins to arrive and when it has finished. It must also know the duration of the each signal.
Internet Protocol version 4 is the current standard “IP” protocol used with Transmission Control Protocol/Internet Protocol (TCP/IP), which is the protocol for Internet addressing. Like the Open System Interconnection (OSI) model, TCP/IP has its own model. The TCP/IP network model represents reality in the world, whereas the OSI model represents an ideal. The TCP/IP network model has four basic layers. The first layer, Network interface layer, deals with all physical components of network connectivity between the network and the IP protocol. Next the Internet layer contains all functionality that manages the movement of data between two network devices over a routed network. Then the Transport layer manages the flow of traffic between two hosts or devices, ensuring that data arrives at the application on the host for which it is targeted. And last, the Application layer acts as final endpoints at either end of a communication session between two network hosts (Tetz).
A computer network is a group of interconnected computers that can accomplish many important tasks. To define computer networking you should define networks. A network is composed of two or people or objects, using a common language, and they have something to share. In computer networking the two or more objects are the computer or terminal. This can consist; have an IBM 3270 terminal and accompanying mainframe, to a stand-alone computer. The computer is usually an IBM PC personal computer or clone licensed copy of a PC, usually cheaply made. The common language or protocol is necessary for the communicators to be able to understand each other. We take for granted simple things like who talks first, how long they talk, and how to end a conversation. A protocol addresses these and more. The common protocol is Transmission Control Protocol (TCP/IP). TCP/IP is the protocol of the Internet. Internet is actually the short form of the word Internet work. Internet work means a network of networks. At one time, all of the different networks used different protocols. A user could talk to others on their network, but not to someone on a different network. The protocol TCP/IP solves this problem. It is what allows a person on one network to communicate with a person on a different network.