Lesson 2: The OSI and TCP/IP Models Flashcards
The top layer of the OSI model. This layer is the closest to the end user. I synchronizes software applications and end-user processes.
Application Layer
The basic unit of information storage; a single binary digit that is either 0 or 1. The term ____ is also used to describe the encapsulation component when data reaches the Physical layer of the OSI model.
Bits
A method for compacting data by removing redundant information, so that systems can send more data along the network in a given amount of time without making any changes to the hardware.
Compression
A network communications protocol that does not ask for verification that a data packet has successfully reached it’s destination.
Connectionless Protocol
A type of network communications prorocol that asks for verification that a packet has successfully reached it’s destination before sending another packet out.
Connection-Oriented Protocol
The infornation that a computer program, software application or networking device operates on. In the top 3 levels of the OSI model (Application, Presentation, and Session layers), the encapsulation unit is referred to as data. In all other OSI levels, the encapsulation unit goes by other names. (See also “Bits,” “Frame,” “Packet,” and “Segment.”)
Data
The second layer of the OSI model, concerned with the protocols and transferring data frames between network nodes. This layer is divided into 2 sublayers: the Logical Link Control (LLC) sublayer and the Media Access Control (MAC) layer.
Data Link Layer
The reverse process of capsulation.
De-Encapsulation
True 2-way communications between 2 devices that can transmit or receive at the same time.
Duplex
The process of taking data from a previous layer of the OSI model and carrying it forward into the next layer.
Encapsulation
A process which allows either the header or the entire data packet to be encoded using a predetermined algorithm in such a way that if an eaves-dropper on the network can intercept the data as it’s transmitted, he still can’t understand it without knowing how to decode it.
Encryption
What a data packet becomes known as when it reaches the Data Link layer of the OSI model (See also “bits,” “data,” and “segment.”)
Frame
A method that a specific frame type or protocol uses to delineate, or define, to the computer the beginning and end of any given frame.
Frame Synchronization
A category of communication in which both devices can send and receive communication at the same time.
Full-Duplex
A category of communication in which a device can either send communication or receive communication, but cannot do both at the same time.
Half-Duplex
A series of data fields added by a protocol at a given OSI model layer to data received from a protocol at the layer above. These data fields contain information which describes what the corresponding layer at the destination system should do with the data.
Header
A layer that occupies more or less the same area on the TCP/IP model as the Network layer does on the OSI model and performs pretty much the same job. The _____ layer also performs many of the functions of the Logical Link Control (LLC) sublayer of the OSI model’s Data Link layer.
Internet Layer
A network address used as kind of a placeholder as data is moved across different computers and logically assigned depending on the Network layer protocol in use.
Logical Address
A sublayer of the OSI model’s Data Link layer that in some ways resulted in the creation of the IEEE 802.2 standard.
Logical Link Control (LLC) Sublayer
A sublayer of the OSI model’s Data Link layer that provides access to the media.
Media Access Control (MAC) Sublayer
The last layer of the TCP/IP model that does much of the job of the Media Access Control (MAC) sublayer of the Data Link layer and the Physical layer of the OSI model.
Network Interface Layer
The layer of the OSI model responsible for moving data packets from one end of the network to the other.
Network Layer
A reference framework designed to explain how different networking technologies work together and interact.
OSI Model
What a data segment becomes when it reaches the Network layer of the OSI model (See also “bits,” “data,” and “frame.”)
Packet
The binary address that every network device is given when it is created by it’s manufacturer. (See also “MAC Address.)
Physical Address
The bottom level of the OSI model that deals with all aspects of physically moving data from one computer to the next. This layer covers the network’s cables and equipment.
Physical Layer
A unique address inside the computer that is associated with a specific protocol, service or application.
Port Address
The layer of the OSI model concerned with how data is presented to the network.
Presentation Layer
A predefined and widely accepted set of rules used to describe exactly how a specific task is to work in a network environment.
Protocol
A group of networking protocols designed to work together to carry out all functions needed for data to be communicated across a network.
Protocol Suite
The ability of various network devices and their related software to move data packets successfully from their source location to their destination locations no matter how far apart they are.
Routing
What data is called after it centers the Transport layer of the OSI Model. (See also “bits,” “frame,” and “packet.”)
Segment
The layer in the OSI model that’s responsible for managing the dialog between network devices.
Session Layer
A category of communication in which a device can either broadcast or receive but cannot do both.
Simplex
Contains additional information added by the Data Link layer that deals with error correction
Tailer
A networking reference framework based on the TCP/IP protocol suite and offered as an alternative to the OSI model.
TCP/IP Model
The ability to take data transmitted by one type of computer and change it so that another type of computer can understand it.
Translation
The layer of the OSI model that is concerned with taking data from the higher layers and breaking it down into smaller pieces, called segments that can be sent along to lower layers for actual transmission.
Transport Layer
