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34 Cards in this Set
- Front
- Back
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OSI |
Open Systems Interconnection model |
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Seven Layers of OSI |
PDNTSPA Data Link Network Transport Session Presentation Application
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Physical Layer |
Moves bits between computer memory and the physical communication link. Implemented by network interface hardware, network interface card drivers, and the OS. |
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Data Link Layer |
Moves data between directly connected nodes.
Data link technologies: Wifi and Ethernet
All members of a LAN are considered directly connected. |
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Network Layer |
Handles communication between nodes that may not be directly connected.
(1) Addressing - addresses on different networks may not match
(2) Routing - figuring out the path |
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Transport Layer |
Provides process to process communication. TCP/IP has two main protocols at the transport layer: TCP and UDP. |
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Session Layer |
Keeps track of sessions. So a person can log in to Amazon and doesn't have to send their username and password with each request. |
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Presentation Layer |
Prepares data for network transmission. Data compression, encryption, byte order. |
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Application Layer |
Concerned with carrying task for end users. Uses text based protocols and binary protocols. |
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How does the TCP/IP stack differ from the OSI protocol stack? |
TCP / IP has the Session Layer, Presentation Layer, and Application Layer all rolled into the Application Layer. If someone wants to use Session or Presentation, then they're responsible for the implementation. |
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End Systems
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The systems that users interact with
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Hosts |
A computer or other device connected to a network with a network layer host address. |
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Network addresses |
An identifier for a node or network interface. |
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Network interfaces |
System's interface between two pieces of equipment or protocol layers in a computer network. |
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Data packet |
A formatted unit of data carried by the network. |
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Data frame |
the unit of transmission in a data link layer protocol, and consists of a link-layer header followed by a packet |
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Router |
A device (usually hardware) that forwards data packets between computer networks. |
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Packet switch |
A device that directs data packets to destinations on a network and associates addresses w/ segments based on packets being sent. Learning switch. |
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Ethernet |
LAN technology. Currently uses switches. Star topology. Guided. |
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WiFi |
LAN Technology. Broadcast. Wireless. |
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Ethernet switch |
Used on a LAN to direct packets. Learns to associate addresses w/ segments based on packets sent / received. |
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Ethernet hub |
Hubs broadcast received packets to every other segment. |
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Communication link |
Connecting one location to another for the purpose of sending a receiving digital information. |
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Guided and unguided transmission media
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Guided fiber optic, coax, twisted pair.
Unguided wireless |
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Broadcast link
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More than one device is linked to the media |
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Point to point link |
Two stations connected by link. Transmission is directed at specific node. Only that node receives.
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Internetwork |
A network of computer networks - interconnection of computer networks
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Transmission delay |
The amount of time required to push all of a packets bits into a wire. |
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Propagation delay |
The amount of time it takes for a signal to travel from one destination to another. |
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Queueing delay |
Delay caused when packets arrive faster than they can be processed, leading to the router queueing them for processing. |
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Processing delay |
The time it takes for routers to process packet headers. |
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Circuit switching |
A dedicated communications channel is established for the duration of the transmission. |
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Packet switching |
Divides communications into packets that are transmitted individually, in contrast to circuit switching. |
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Routing |
Determining the best path from one node to another on a network. |
