Exam (elaborations)
CNIT 240 Final Review Exam Questions And Answers 100% Solved.
- Course
- Institution
CNIT 240 Final Review Exam Questions And Answers 100% Solved.
[Show more]
Content preview
CNIT 240CNIT 240 Final Review Exam Questions
And Answers 100% Solved.
What are the components of communications? - ✔✔✔ - - source
- destination
- message
- transmission medium
What is a layered approach to communications? - ✔✔✔ - - provides a logical breakdown in
functions, operations, responsibilities, maintainance, and management of a system
- each layer performs a specific set of functions or tasks
- layers rely on other layers to perform their specified tasks
- use defined interfaces to communicate between layers
- provides the opportunity to improve, enhance, replace components of the system without
need to replace entire system
List some communication reference models - ✔✔✔ - - Open System Interconnection (OSI)
- TCP/IP
- Input-Process-Output (IPO)
What is the OSI model? - ✔✔✔ - - defines 7 layers in order to describe end-to-end
communications between any two systems
- provides open interconnections between layers (ie. can support multi-vendor environments)
What are some of the OSI model's rules for communication? - ✔✔✔ - - communication
between layers is handled in specified (defined) manner
CNIT 240 Page 1
,CNIT 240
- each layer is only able to communicate with its adjacent layers
- each layer relies on layers below it to perform their specified function
- each layer relies on layers above it to perform their specified function
What are the 7 layers of the OSI model? - ✔✔✔ - "Please do not throw sausage pizza away"
(bottom to top)
- physical layer
- data link layer
- network layer
- transport layer
- session layer
- presentation layer
- application layer
What is the physical layer of the OSI model? - ✔✔✔ - - responsible for transmission and
receipt of bit stream to/from nodes
- solely concerned with signaling techniques (activating, maintaining, terminating physical
circuit)
- electrical, mechanical, and functional control of data communications circuits in networks
- will pass received information up to layer 2
- does NOT include the physical media!!
- passes bit stream to layer 2 for frames/cells construction
- provides buffering for frame fragments
- performs a simple "error-detection" routine (at signal level)
CNIT 240 Page 2
,CNIT 240
What is the data link layer of the OSI model? - ✔✔✔ - - responsible for providing POINT-TO-
POINT validity of the data (via point-to-point checking/correction; CRC is most common
approach)
- not all LAN architectures can support reliable delivery (must verify frame integrity;
acknowledge that each frame was received intact)
- UTILIZES FRAMES!
- converts data to frames
- independent address architecture from other layers
- procedures and protocols for reliably operating communication links
What are the data link sub-layers? - ✔✔✔ - MAC functions
- ensures access to shared medium
- responsible for framing data prior to physical transmission
- transmitting frames between end nodes using functionality of physical-layer devices
LLC functions
-provides reliable delivery of layer 3 PDUs through service access points
- organizing an interface to network layer, which is directly adjacent to it
- ensures reliable frame delivery with predefined reliability level
What is the network layer of the OSI model? - ✔✔✔ - - enables INTERNETWORKING!
- establishes routes between source and destination NETWORKS
- END-TO-END!
- relies on higher layer protocols for error detection and correction
CNIT 240 Page 3
, CNIT 240
- UNRELIABLE!
- not logically required for connectivity on a LAN (layer 3 services are often required by
applications that do interface directly with layer 2)
- utilizes PACKETS (reliable)! or datagrams (unreliable)
- converts DATA TO PACKETS!
- includes routable/routed protocols (routable: IP, IPX, AppleTalk; routed: RIP, OSPF, BGP)
What is the transport layer of the OSI model? - ✔✔✔ - - responsible for HOST-TO-HOST
integrity of transmission
- functionality provided beyond LAN segment
- detects damanged or lost packets and generates retransmit requests (SYN, SYN-ACK, ACK, etc)
- re-sequences packets
- depends on layer 3 protocol being used (TCP, UDP, etc)
- utilizes MESSAGES or SEGMENTS
- converts DATA TO SEGMENTS
What is the session layer of the OSI model? - ✔✔✔ - - establishes, maintains, and terminates
HOST-TO-HOST INTERACTIVE SESSIONS
- used to uniquely identify a service, application, or function on a host via PORTS
- COMMUNICATION COORDINATION!
What is the presentation layer of the OSI model? - ✔✔✔ - - responsible for managing the way
data is presented
- code conversion/translation (ASCII, EBCDIC, Unicode, etc; encryption & text compression)
- data syntax and structure
CNIT 240 Page 4
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Boffin. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $13.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67866 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now
