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| | Data link layer - Wikipedia, the free encyclopedia |
 | | The data link layer is often implemented in software as a "network card driver". | | | The data link layer provides the functional and procedural means to transfer data between network entities and might provide the means to detect and possibly correct errors that may occur in the Physical layer. | | | Other data link layer protocols, such as HDLC, are specified to include both sublayers, although some other protocols, such as Cisco HDLC, use HDLC's low-level framing as a MAC layer in combination with a different LLC layer. |
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http://en.wikipedia.org/wiki/Data_link_layer
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| | NOAAPORT Data Link Layer Protocol |
| | The NBS encodes the data using nonreturn-to-zero (NRZ) encoding. | | | With this encoding method, only a minimal amount of clocking information is available in the data stream in the form of transitions on bit-cell boundaries, which do not allow for self-clocking. | | | This field contains the data packet that is further defined in the SBN protocol. |
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http://www.nws.noaa.gov/noaaport/html/datalink.shtml
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| | CCNA Study Notes - OSI - Data Link Layer |
| | The Data Link layer uses a calculated value called the CRC (Cyclic Redundancy Check) that's placed into the Data Link trailer that's added to the message frame before it's sent to the Physical layer. | | | The transport layer adds a header indicating that an HTTP process is requested. | | | Packets and datagrams are converted into frames and the Data Link header is added. |
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http://defoenet.com/ccna/osi_l2.html
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| | Data Link Layer |
| | Data link layer algorithms may be embedded in the network hardware (rather than running as software process on a machine). | | | Assume a single link from A to B. Assume service provided by physical layer is that it will deliver bits to B in the order in which they are sent. | | | Data link layer sends frames - small fixed (or max) length pieces of data. |
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http://www.compapp.dcu.ie/~humphrys/Notes/Networks/data.link.html
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| | The Data Link Layer Protocols |
| | The purpose of the data link layer is to transfer blocks of data without error between two adjacent devices. | | | The primary station is responsible for the organisation of data flow and for the link level error recovery procedures. | | | The physical link has no inherent storage capacity, therefore the delay involved is the propagation delay over the link. |
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http://www.dsi.unive.it/~franz/reti/dll/Protocolli.html
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| | Data Link Layer Processing © AA VERSTRAETE |
| | The data link is the last layer in the protocol suite that treats the data as a logical data string held in the computer's main memory and processed by the communication's software. | | | The data link layer takes posession of the protocol data unit that has been received by the data communications equipment [DCE] operating at the physical layer. | | | Peer-to-peer dialogue (dotted line): The sending and receiving data link layers confirm any transmission protocol conventions that may be required to transfer the message to the next network node. |
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http://www.smeal.psu.edu/misweb/datacomm/ID/OSI_RDL.HTM
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| | The DataLink Layer |
| | Example data structures and library routines required for data link layer | | | The overall task of the data link layer is to make the physical line appear error free to the higher layers (this is usually called a virtual circuit). | | | The host computers past data to/from the IMPS (interface message processors) which handle the communications over the physical communications link. |
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http://www.cse.dmu.ac.uk/~cfi/Networks/DataLink/DataLink0.htm
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| | The Data Link Layer |
| | Layer 2, the Data Link layer, is where Ethernet lives. | | | Abbreviated STP, a link management protocol that is part of the IEEE 802.1 standard for media access control bridges. | | | The capability to send data to only the correct host was a huge advance in switching because collisions became much less likely. |
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http://www.webopedia.com/DidYouKnow/Computer_Science/2006/data_link_layer.asp
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| | Data-Link Layer |
| | The data-link layer provides error-free transfer of data frames from one computer to another over the physical layer. | | | Establishment and termination of logical links (virtual-circuit connection) between two computers identified by their unique network adapter addresses. | | | Instead, reliable data delivery is provided by protocols operating at the transport layer. |
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http://www.microsoft.com/resources/documentation/Windows/2000/server/reskit/en-us/cnet/cnfh_osi_ltkh.asp?frame=true
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| | The Data Link Layer |
| | The main task of the data link layer is to take a raw transmission facility and transform it into a line that appears free of transmission errors in the network layer. | | | Since the physical layer merely accepts and transmits a stream of bits without any regard to meaning of structure, it is up to the data link layer to create and recognize frame boundaries. | | | Another issue that arises in the data link layer (and most of the higher layers as well) is how to keep a fast transmitter from drowning a slow receiver in data. |
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http://www2.rad.com/networks/1994/osi/datalink.htm
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| | Data Link Layer |
| | SAP’s are defined in headers that identify the logical port assigned to the protocol | | | All encapsulated data plus the data link information | | | SAP’s move data from one layer to the next and to the correct application |
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http://www.brazosport.cc.tx.us/~slannen/netess/chap6
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| | Chapter 6: Data Link Layer |
| | The data link layer manages point to point communication and frames data for the physical layer to send over the media. | | | The Media Access Control (MAC) sublayer handles coordination of and contention for use of the media (particularly important in shared media situations), while the Logical Link Control (LLC) layer is an interface between MAC and the network layer (layer 3). | | | Error detection is performed by adding additional information to the data which might allow the receiver to recognize an error. |
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http://telecomm.boisestate.edu/is380.f97/datalink.htm
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| | Data Link Layer Components |
| | The data link layer consists of drivers that directly handle communication with the physical medium. | | | The PPP link can serve as an additional network interface apart from the existing default network interface, or it can be the default network interface on the target, causing PPP to serve as a network back end for the target server on the host. | | | Once a link is established, an ID/password pair is sent repeatedly by the peer to the authenticator until authentication is acknowledged or the connection is terminated. |
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http://www.ia.agh.edu.pl/personal/pszwed/kss-lab/wind-docs/vxworks/netguide/c-dll.html
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| | Data-Link Layer - 2 |
| | Builds on the transmission facility provided by the physical layer to transform it into a link that appears to the network layer above to be free of transmission errors. | | | There are a number of ways of trying to remove the errors introduced by the physical layer. | | | Concerned with the transmission of data between two directly connected devices across a single link. |
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http://www.eeng.dcu.ie/~murphyj/tc2/dc2000/tsld018.htm
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| | Chapter 7: The OSI Data-Link Layer |
| | Identify the characteristics of the three transmission synchronization techniques that can be used at the Data Link layer. | | | This layer tells us how the network is physically accessed, how some errors are handled, how data flow is handled and how entities on the network are addressed. | | | Error Control allows the receiver to use the frame numbers in a window to let the sender know when a frame was not received or when the CRC check does not match. |
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http://home.att.net/~s.k.vincent/250_7.htm
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| | NETBOOK - Q & A on Data Link Layer in OSI |
| | Q: The Data Link layer of the OSI model is sometimes subdivided into a media access control (MAC) and a logical link control (LLC) layer. | | | For example, in X.25, a link layer frame includes a sequence number, and the receiver must acknowledge each frame. | | | A network analyzer can tell from the values in the type field (small values are lengths, which mean an LLC/SNAP header is located in the first octets of the data area; large values are types, which mean no LLC/SNAP header is included). |
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http://www.netbook.cs.purdue.edu/othrpags/qanda114.htm
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| | Data Link Layer Protocols |
| | The remote Network Layer peer should receive the identical message generated by the sender (e.g., if the data link layer adds control information, the header information must be removed before the message is passed to the Network Layer). | | | Nonetheless, the ISO reference model suggests that the data link layer provide such a service, and we now examine the protocols that provide such a service. | | | Important: TC sublayer must know about header information above it. |
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http://www.cs.wpi.edu/~cs4514/b98/week3-dllprot/week3-dllprot.html
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| | Webopedia: The 7 Layers of the OSI Model |
| | This layer provides switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. | | | The data link layer is divided into two sublayers: The Media Access Control (MAC) layer and the Logical Link Control (LLC) layer. | | | This layer provides transparent transfer of data between end systems, or hosts, and is responsible for end-to-end error recovery and flow control. |
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http://www.webopedia.com/quick_ref/OSI_Layers.asp
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| | ISA General Information |
| | This technical report acts as a tutorial addressing those who are not familiar with ISA's Fieldbus Data Link Layer (DLL) documents. | | | links separate parts of the ISA DLL documents relevant to either the same subject or to correlated items; and | | | presents the specific reasons why certain features in ISA's DLL documents are included; |
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http://www.isa.org/?template=Ecommerce/ProductDisplay.cfm&ProductID=2613
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| | Data link layer |
| | When the frame arrives the destination machine, it computes the check sum again if the newly computed checksum is different from the old one an error has been occured and the data link layer takes necessary steps to deal with it. | | | Data link layer has several functions to perform they are providing a well defined service to the network layer, determining how the bits of the physical layer are grouped into frames, dealing with transmission errors, regulating the flow of frames so that slow receivers are not swamped by fast senders, and general link management. | | | The principal service provided by the data link layer to the network layer is the transmission of data from the source network layer to destination network layer. |
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http://homepages.uel.ac.uk/u0214590/data.html
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| | Role of the Data-link layer |
| | The Data-link layer in the receiver extracts the data and passes the data to its Network layer. | | | An important function of the Data-link layer is the establishment of reliable and efficient communication with another Data-link layer peer. | | | We have seen that the Physical layer is responsible for actually transmitting bits over a transmission medium and in general a bit stream given from the higher layer is coded and modulated to do this. |
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http://www.cs.mu.oz.au/353/notes/node53.html
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| | Data Link Layer and IEEE |
| | RFC 1042 defines the IP to link layer data encapsulation for networks using the IEEE 802 standards. | | | The 802 standards define the two lowest levels of the seven layer network model and primarily deal with the control of access to the network media. | | | The network media is the physical means of carrying the data such as network cable. |
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http://www.comptechdoc.org/independent/networking/guide/netieee.html
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| | OSI Model - Data Link Layer |
| | The data link layer performs various functions depending upon the hardware protocol used, but has four primary functions: | | | The CSMA/CD protocol that Ethernet uses to control access to the common network bus could be said to occur at the data link layer of the OSI model or could also be called a data link function. | | | The data link Layer is the second layer of the OSI model. |
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http://www.inetdaemon.com/tutorials/theory/osi/data_link.shtml
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| | Define data link layer - a definition from Whatis.com |
| | The Data-Link Layer is the protocol layer in a program that handles the moving of data in and out across a physical link in a network. | | | The Data-Link Layer is layer 2 in the Open Systems Interconnect (OSI) model for a set of telecommunication protocols. | | | The Data-Link Layer assures that an initial connection has been set up, divides output data into data frames, and handles the acknowledgements from a receiver that the data arrived successfully. |
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http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci211971,00.html
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| | Configuring Data Link Layer Interfaces |
| | Figure 1-13 shows the structure of the Frame Relay protocols with the physical layer as the foundation. | | | The HDLC layer is on top of the physical layer and can support flexible assignment of physical resources. | | | For Frame Relay, the physical layer can be CE1, E3, CT1, T3, or a fractional service, as supported by the different line module ports. |
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http://www.juniper.net/techpubs/software/erx/erx403/swconfig-system-basics/html/network-planning10.html
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| | Networking Technology - Questy's study guide |
| | The lower sub-layer of the Data Link layer, the Media Access Control (MAC), performs Data Link layer functions related to the Physical layer, such as controlling access and encoding data into a valid signaling format. | | | The Data Link layer deals with issues on a single segment of the network, the Network layer deals with issues spanning networks. | | | The upper sub-layer of the Data Link layer, the Logical Link Control (LLC), performs Data Link layer functions related to the Network layer, such as providing and maintaining the link to the network. |
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http://www.computerguru.net/tech/netw31.htm
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| | Data Link Layer |
| | Layer(DLC--Data Link Control) originates from this) for the connection must be managed | | | Link Control Methods(for Connection-Oriented Services)--A link(the name for OSI second | | | SYN SYN Count(2 bytes) data characters …….. error detect codes |
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http://www.ecst.csuchico.edu/~sim/278/notes/NOTE9_1.htm
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