CAB240 Lecture Notes - Lecture 11: Osi Model, Network Interface Controller, Internet Protocol Suite
Document Summary
Data transmission: electronic data is binary digits (bits) 0 and 1, group into bytes: 8 bits. Sent as packets: packet header: has control information (source and destination addresses, sequencing info, packet body: payload - binary data to be transmitted. Essentially, a set of rules defining format for messages exchanged between entities. Communication protocol stacks: network communications use multiple protocols, think of these protocols arranged in a layered structure, each layer performs different types of activities required to enable communications between devices, two well-known models: Iso open systems interconnection (osi) model: 7-layer model. Ietf internet protocol suite: 4-layer model, application, prepares user messages, each application protocol has unique message format, transport, converts messages to packets, use ports for different applications on same host. Internet: converts packets to datagrams, hosts have unique ip addresses (ipv4: Link (network access: physical layer associated with hardware, transmission of communication as bits, commonly known as tcp/ip - includes two well-known protocols, transmission control protocol.
