Lesson 1 Explaining the OSI and TCP/IP Models Flashcards
In this lesson, you will: • Describe the functions of the layers of the OSI model. • Describe the functions of the layers of the TCP/IP model.
What Are The 7 Layers of OSI Model ?
Layer 1 Physical Layer, Layer 2 Data-Link Layer, Layer 3 Network Layer, Layer 4 Transport Layer, Layer 5 Session Layer, Layer 6 Presentation Layer, Layer 7 Application Layer,
OSI Stands For What?
Open System Interconnection
TCP/IP Top Layer Is Called Application & Is Combined of What 3 OSI Model Layers?
Layer 5 Session Layer,
Layer 6 Presentation,
& Layer 7 Application Layer
TCP/IP Host-To-Host Transport Layer Is the Same as Which OSI Layer?
Layer 4 Transport Layer
TCP/IP Internet Layer Is the Same as Which OSI Layer?
Layer 3 Network Layer
TCP/IP Network Interface Layer is a combination of Which Two OSI Layers?
Layer 2 Data-Link Layer & Layer 1 Physical Layer
What Is a Network Boundary?
Two or more computer systems linked together by some form of transmission medium that enables them to share information
What Are Nodes?
Nodes are the devices that communicate on the network
What Are Links?
Links are the communications pathways that are found between Nodes
PDU Stands for What?
Protocol Data Units
What are Two of The Most important functions of Protocols?
Addressing and Encapsulation
What Function Direct Data to what path it will take?
Addressing
Which Devices Can Be Found at Layer 1 Physical Layer?
Transceiver, Media Converter, Hub/Repeaters & Modem
MAC Addresses & Switches are found at which Layer?
Layer 2 Data-Link Layer
Which device is used to amplifies an electronic signal so as to extend the maximum allowable distance for a media?
A Repeater
Bits Encoding/ Transmission takes place at which Layer?
Layer 1 Physical Layer
Switches found at Layer 2 the Data Link Layer forward frames from one port to another port based off what?
The Mac Address plugged into the switch port
Routers found in the 3rd layer Network Layer sends what to other routers by moving data between networks?
Packets
A NIC, Bridge, Switches & Wireless Access Point (WAP) are devices found at which Layer?
Layer 2 Data-Link Layer
IP Address, ICMP, IGMP, ARP, IPsec describe devices found at which layer?
Layer 3 Network Layer
A method of grouping data into packets that are transmitted over a digital network
Packet Switching
A method of implementing a telecommunications network in which two network nodes establish a dedicated communications channel through the network before the nodes may communicate.
Circuit Switching
A form of switching in which data is broken into packets but with the add ability of being stored or forwarded (i.e., like email) goes by what name?
Message switching
OSPF is short for?
Open Shortest Path First
Router Information Protocol Is also called what?
RIP
A request to find the best available route to the destination, when sending a message.
Route Discovery
Flow Control prevents what from occurring?
It prevents a sender from sending data faster than the receiver can get it
Allowing packets to be sent over more than one link & routes for faster service is named what?
Packet Reordering
Layer 4 is named what?
Transport Layer
UDP (User Datagram Protocol) is connectionless protocol that defined by RFC 768
that is used for?
Used for performance but can be unreliable
The Network Layer identify each application by assigning what to it?
It identifies applications by assigning port numbers to them
TCP (Transmission Control Protocol) ensures reliable data delivery through a process that is named?
Three-Way Handshake in which normally a client device would initiate a connection with a server. The client sends a sequence number packet (with the SYN bit set) to the server. The packet contains the random sequence number (e.g., 5432) which marks the beginning of the sequence numbers for data that the server will transmit.
The Layer that represents the dialog control functions that administer the process of establishing the dialog, managing data transfer, and then ending (or tearing down) would be which layer?
Layer 5 The Session Layer
What is happening at the Session Layer?
The management of a session between two devices and also firewalls protections
One-way/simplex—Only one system is allowed to send messages; the other only receives.
Two-way alternate (TWA)/half-duplex—The hosts establish some system for taking turns to send messages, such as exchanging a token.
Two-way simultaneous (TWS)/duplex—Either host can send messages at any time.
Are the 3 modes of which layer?
Layer 5 The Session Layer
Compression, Encryption and Formatting all take place during which layer in the OSI process?
Layer 6 The Presentation layer
The Presentation Layer does what?
Transforms data between the format required for the network and the format required for the application
What is the main purpose of layer 7 (Application Layer) within the OSI Model?
To provide an interface for software programs on network hosts that have established a communications channel through the lower-level protocols to exchange data.
Network card driver (Layer 2), Sockets/Winsock (Layer 5) & Web Browsing (Layer 7) are all examples of what?
They are examples of API’s (Application Programming Interface) software.
A dedicated path established between two locations, such as two routers or two modems.
A Circuit
The ability for one host to forward information to another using any available path
Packet Switching
A packet switching protocol is described as ?
Robust because it can automatically recover from communications link failures. It re-routes data packets around an internetwork of available paths. If transmission lines are damaged or if a router fails to respond, it can use any available network path that remains.
The process for adopting Internet standards revolves around the production of documents called ?
Requests for Comments (RFCs)
