Chapter 9 Ethernet

Chapter 9

This chapter focuses the different layers of OSI and TCP/IP and hoe they support networks to communicate. The functional protocol and services for the TCP/IP protocol suite in the upper layer is maintain  by the internet engineering task force. The Ethernet operates across the two layers of OSI model the physical layer and the data link layer. The Ethernet is now the predominant LAN technology in the world. Ethernet at layer 1 involves signals, bit streams that travel on the media physical components that put signals on media and various topologies. The Ethernet at layer two connects to the upper layers via logical link control and uses addressing schemes to identify devices. Ethernet separates the function of the data link layer into two distinct sub layers the logical link control sub layer and the media access control sub layer. The logical link control sub layer handles the communication between the upper layers and the networking software and the lower layer typically the hardware. The media access control sub layer is the lower Ethernet sub layer of the data link layer. MAC is implemented by hardware typically in the computer network. Media Access Control  controls the placement of the frames on the media and the removal of frames from the media. Logical topology of the Ethernet is a multi-access bus. This means that all nodes in the network segment receive all frames transmitted by any node on that segment. Ethernet specifies and implements encoding schemes that enables the frame bits to be carried as signals across media. Ethernet technology was first established in 1970 with the program called ALOHANET a digital radio network design to transmit information over a shared radio frequency between the Hawaiian Islands. The first version of  Ethernet  incorporated a media access method known as carrier sense multiple access with collision and detection. It manages the problems that result when multiple devices attempt to communicate over a shared physical medium. The early version of Ethernet uses coaxial cable to connect computers in a bus topology. The Ethernet frame size gas an standard of minimum frame size as 64 bytes and the maximum as 1518 bytes in 1998 it was extended its maximum allowable frame size to 1522. The frame size was increase to accommodate the virtual local area network. The MAC address was created to assist determining the source and destination address within your computer.