Data Link Layer Protocols Characteristic and Purpose

Data Link Layer Protocols Characteristic and Purpose

In this post we explain the Data Link Layer Protocols of the OSI model (Layer 2) as well as its characteristics, purposes. 

WHAT IS THE DATA LINK LAYER

The OSI data link layer is responsible for the exchange of Ethernet frames between the source and destination nodes through a physical network medium. The data link layer receives packets from a higher layer protocol and directs them to a protocol of the same characteristics (IPv4 or IPv6). This upper layer protocol does not need to know what media the communication uses.

DATA LINK SUB-LAYERS

The data link layer is divided into two sub-layers:

• Logical Link Control: communicates with the network layer, places information in the frame that identifies which network layer protocol is used for the frame. This information allows several Layer 3 protocols, such as IPv4 and IPv6, to use the same network interface and the same means.
• Media Access Control: defines the processes of access to the medium that the hardware performs. It provides data link layer addressing and access to various network technologies.

MEDIA ACCESS CONTROL

The technique used to place and remove the plot of the media is called the method of access control to the media.

PROVISION OF MEDIA ACCESS

During the same communication, different methods of access control to the medium may be necessary. Each network environment that packets encounter when they travel from a local host to a remote host can have different characteristics.

DATA LINK LAYER STANDARDS

Finally, we will see some standards that govern Layer 2. Unlike the protocols of the upper layers of the TCP / IP suite, data link layer protocols are generally not defined by the request for comments (RFC).

DATA LINK LAYER STANDARDS
Standardization body	Network standards
IEEE	802.2: Logical link control (LLC) 802.3: Ethernet 802.4: Token bus 802.5: token pass 802.11: wireless LAN (WLAN) and mesh (Wi-Fi certification) 802.15: Bluetooth 802.16: WiMax
ISO	High level data link control (HDLC) ISO 9314: FDDI media access control (MAC)
ITU-T	G.992: ADSL G.8100 - G.8199: MPLS aspects of transport Q.921: ISDN Q.922: Frame Relay
ANSI	X3T9.5 and X3T12: Fiber Distributed Data Interface (FDDI)