Elementary data link protocols must agree at the most rudimentary level. The data frame must be constructed from this level, and all protocols must agree.
The role is to transfer frames to packets
Network Layer This layer addresses the data. It adds an IP address which allows our data to flow across networks. The protocols involved in this layer are IP and IPX. Data Link Layer This layer provides the functional and procedural means to transfer data. It also corrects any errors that may occur in the Physical layer. The protocols used at this layer are media access control and logical link control.
Damaged frames are discarded. Retransmission - if needed - is handled by higher-layer protocols, like TCP.
Networking protocols, such as TCP/IP, enable computers to exchange data with each other in a meaningful, organized, and efficient way. Computer protocols are similar to human language - if you speak English and you meet someone who speaks German, the protocols (languages) you use to exchange information are incompatible with each other. It is only when you both speak the same language that you can understand each other. Similarly, computers rely on protocols to ensure each computer "understands" what the other computer is sending it. Just as with humans, both computers must use the same protocol if they are to exchange information with each other successfully. Follow the Related Link below to view a Wikipedia article on this topic.
Logical link control manages traffic in the Open Systems Interconnection and identifies line protocols including NetBIOS or NetWare. Medium Access Control is responsible for sharing physical connection to the network amongst numerous computers via Ethernet.
The most common WAN data-link protocols are: 1. HDLC 2. PPP 3. Frame Relay 4. ATM
bit
Here's what you should know: Data link layer protocols must be concerned with the rules for transmitting data across the network media, particularly with encoding and carrying "frames" of data. Although this layer includes providing error detection and notification by adding the Cyclic Redundancy Check (CRC), the Transport Layer is primarily responsible for end-to-end error-free message delivery. WAN Data-Link protocols primarily define how data frames should be packaged for different types of networks. To quote: The data link protocols available for WAN communications define how networks will carry the data frames on a given data link. The data link protocols used for WANs come in three categories: 1. Interface to IBM enterprise data centers: SDLC 2. WAN connections using peer devices: HDLC & PPP 3. Switched or relayed services: X.25/LAPB, Frame Relay, ISDN/LAPD, ATM. Some of these protocols provide functionality as high as in the Network layer of the OSI, and all of these protocols transfer data over a WAN data link.
Protocols are a commonly agreed-upon set of rules for common communication between devices. At the data link layer they have to agree on the rules of how the frame is constructed, otherwise there would be no correct way to deliver frames to the intended systems.
The role is to transfer frames to packets
Atm frame relay
atm and frame-relay
Data link layer protocols like PPP and HDLC define how data is encapsulated for transmission across a WAN link.
TELNET
physical layer.
Distance vector protocols compute their routing tables before sending routing updates; link-state protocols do not.
The X.25 standard specifies protocols at the Physical, Data Link, and Network Layers of the OSI Model.Broadband Cable functions at both the Physical, and Data Link Layers.ISDN functions at the Physical, Data Link, and Transport Layers.DSL, SONET, and T-Carriers function at the Physical Layer.Frame Relay, and ATM function at the Data Link Layer.