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Practical TCP/IP and Ethernet Networking- P11

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Practical TCP/IP and Ethernet Networking- P11: The transmitter encodes the information into a suitable form to be transmitted over the communications channel. The communications channel moves this signal as electromagnetic energy from the source to one or more destination receivers. The channel may convert this energy from one form to another, such as electrical to optical signals, whilst maintaining the integrity of the information so the recipient can understand the message sent by the transmitter | 32 Practical TCP IP and Ethernet Networking 802.1E System load protocol 802.1F Guidelines for layer management standards 802.1G Remote MAC bridges 802.1I MAC bridges FDDI supplement IEEE 802.2 Logical link control This is the interface between the network layer and the specific network environments at the physical layer. The IEEE has divided the data link layer in the OSI model into two sub layers - the media access MAC sub layer and the logical link layer LLC. The logical link control protocol is common for all IEEE 802 standard network types. This provides a common interface to the network layer of the protocol stack. The protocol used at this sub layer is based on IBM s SDLC protocol and can be used in three modes or types. These are Type 1 Unacknowledged connectionless link service Type 2 Connection oriented link service Type 3 Acknowledged connectionless link service used in real time applications such as manufacturing control IEEE 802.3 CSMA CD The carrier sense multiple accesses with collision detection type LAN is commonly - but strictly speaking incorrectly - known as an Ethernet LAN. Ethernet refers to the original DEC INTEL XEROX product known as Version II or Bluebook Ethernet. Subsequent to ratification this system has been known as IEEE 802.3. IEEE 802.3 is virtually identical but not absolutely identical to Bluebook Ethernet in that they differ in two bytes within the frame. The following chapter will deal with this anomaly. Subsequently two additional specifications have been approved viz. IEEE 802.3u 100 Mbps or fast Ethernet and IEEE 8023z 1000 Mbps or gigabit Ethernet . IEEE 802.4 Token bus The other major access method for a shared medium is the use of a token. This is a type of data frame that a station must possess before it can transmit messages. The stations are connected to a passive bus although the token logically passes around in a cyclic manner. This standard is the ratification of the Token Bus LAN developed by General Motors for its .