Network Models Flashcards
What does OSI stand for?
Open Systems Interconnection
What does TCP/IP stand for?
Transmission Control Protocol/Internet Protocol
What is a model?
Simplified representation of the real thing
Who created the OSI seven-layer model?
International Organization for Standardization
What are sets of clearly defined rules, regulations, standards, and procedures that enable hardware and software developers to make devices and applications that function properly at a particular layer?
Protocols
How many layers does the OSI model have?
7
What is Layer 1 of the OSI model?
Physical
What is Layer 2 of the OSI model?
Data Link
What is Layer 3 of the OSI model?
Network
What is Layer 4 of the OSI model?
Transport
What is Layer 5 of the OSI model?
Session
What is Layer 6 of the OSI model?
Presentation
What is Layer 7 of the OSI model?
Application
What is a good acronym to use to remember the seven-layers of the OSI model?
Please do not throw sausage pizza away
Describe an unshielded twisted pair cable.
Usually contains 4 pairs of wires that can transmit and receive data
Anything that moves data from one system to another, such as copper cabling, fiber optics and radio waves is part of what layer of the OSI model?
Layer 1 - Physical
What serves as the interface between the PC and the network?
Network interface card (NIC)
Where do you commonly find a NIC?
Built into the motherboard
What is a MAC address?
Media Access Control address - special firmware containing a unique identifier with a 48-bit value
MAC addresses are always written in ____.
12 hex characters
How many bits does a hex character represent?
4 bits
What does OUI stand for?
Organizationally Unique Identifier
What does EUI stand for?
Extended Unique Identifier
What is a powerful tool that enables you to see electrical pulses?
Oscilloscope
What is a container for a chunk of data moving across a network called?
Frame
What is the unit of data specified by a protocol at each layer of the OSI seven-layer model?
Protocol Data Unit (PDU)
What is the most common wired network technology called?
Ethernet
What indicates what is encapsulated in the frame?
Type field
What devices filter traffic by MAC address?
Switches
Any frame addressed specifically to another device’s MAC address is called a _______.
Unicast frame
What aspect of the NIC talks to the systems operating system( usually via device drivers), handles multiple network protocols and provides flow control?
Logical Link Control (LLC)
What is the only layer of the OSI that has sub-layers?
Layer 2 - Data Link
What aspect of the NIC creates and addresses the frame, adds the NIC’s own MAC address, attaches MAC addresses to the frames, adds or checks the FCS, and ensure that frames are sent along the network cabling?
Media Access Control (MAC)
What layer(s) of the OSI model does a network card work at?
Layer 1 and 2
What type of network is defined as one in which all the computers connect to one switch?
Simple network
What acts like a postal code or telephone numbering scheme for large networks?
Logical addressing
Logical addressing allows you to break up the entire large network into smaller networks called _____.
Subnets
MAC addresses are also known as _____.
Physical addresses
What are several network protocols designed to work together referred to as?
Protocol suite
What is the primary logical addressing protocol for TCP/IP and makes sure that a piece of data gets to where it needs to go on the network?
The Internet Protocol
A _____ is a unique numeric identifier given to every device on a network.
IP address
An IP address is also known as a _____ to distinguish it from the physical address(MAC address).
Logical address
What is a “magic” box that connects each of the subnets and use the IP address to forward data?
Router
Where is an IP address stored?
Systems software
What is a group of bits of fixed maximum size and well-defined format that is switched and transmitted as a complete whole through a network?
Packet
What is the process of chopping requested data into chunks that will fit into a packet, organizing the packets for the benefit of the receiving system, and handing them to the NIC for sending?
Segmentation
What is the process where a receiving system verified and puts together packets into coherent data?
Reassembly
What is a connection less transfer unit designed for quick transfers over a packet-switched network?
Datagram
Data grams are created with the _______.
User Datagram Protocol
What layer of the OSI model deals with segmentation/reassembly softwares and initializes requests for packets that weren’t received in good order?
Layer 4 - Transport
What handles the process of differentiating among various types of connections on a PC?
Session software
What layer of the OSI model handles all the sessions for a system, initiates sessions, accepts incoming sessions, and opens and closes existing sessions?
Layer 5 - Session
What layer of the OSI model translates data from lower layers into a format usable by the Application layer, and vice versa?
Layer 6 - Presentation
What layer of the OSI model refers to the code built into all operating systems that enables network-aware applications and is the most visible part of any network?
Layer 7 - Application
What can programmers use to make their programs network aware and enhance or extend an applications capabilities?
Application Programming Interfaces (API’s)
What is the process of putting packets from one protocol inside the packets of another protocol?
Encapsulation
What is the process of stripping all the extra header information from a packet as the data moves up a protocol stack?
De-encapsulation
What are the four layers of the TCP/IP model?
- Application
- Transport
- Internet
- Link/Network Interface
What layer of the TCP/IP model is any part of the network that deals with complete frames?
Link/Network Interface
What layer of the TCP/IP model deals with the Internet Protocol, including IP addressing and routers?
Internet
What layer of the TCP/IP model combines features or the OSI Transport and Session layers with a dash of Application layer?
Transport
What protocol is used for sending e-mail messages and requires that the e-mail client and server verify that they have a good connection before a message is sent?
Internet Message Access Protocol (IMAP)
What is a protocol used by some older applications, most prominently TFTP(Trivial FTP), to transfer files?
User Datagram Protocol(UDP)
What works on the Transport layer and is the connection-oriented payload of an IP packet?
TCP segment
What are 16-but numbers between 0 and 65535 assigned to a particular TCP/IP process or application?
Port (logical connection)
What is a connection less networking container used in UDP communication?
UDP Datagram
What layer of the TCP/IP model combines features of the top three layers of the OSI model?
Application
Where does a hub send data?
To all the systems connected to the hub.
What uniquely identifies every NIC?
Media access control(MAC) address
What Windows utility do you use to find the MAC address for a system?
ipconfig /all
A NIC sends data in discrete chunks called ____.
Frames
A MAC address is known as a _____ address.
Physical
Which MAC address begins a frame?
A. Receiving system
B. Sending system
C. Network
D. Router
A. Receiving system
What is a special bit at the end of a frame that verifies the data arrived correctly?
Frame Check Sequence (FCS)
Which of the following is an example of a MAC address?
A. 0-255
B. 00-50-56-A3-04-0C
C. SBY3M7
D. 192.168.4.13
B. 00-50-56-A3-04-0C
Which layer of the TCP/IP model controls the segmentation and reassembly of data?
Transport layer
Which layer of the OSI seven-layer model keeps track of a systems connections to send the right response to the right computer?
Session layer