CNIT 344 Exam 1 Answered 2024
1st Layer of the OSI Model - ANSWER-Physical Layer
2nd Layer of the OSI Model - ANSWER-Data Link Layer
3rd Layer of the OSI Model - ANSWER-Network Layer
4th Layer of the OSI Model - ANSWER-Transport Layer
5th Layer of the OSI Model - ANSWER-Session Layer
6th Layer of the OSI Model - ANSWER-Presentation Layer
7th Layer of the OSI Model - ANSWER-Application Layer
At what clock rate does Ethernet operate? - ANSWER-20 MHz
Components of Communication - ANSWER-Message Source -> Encoder -> Transmitter
-> Transmission Medium "The Channel" -> Receiver -> Decoder -> Message
Destination
Describe a parallel connection. - ANSWER-Able to send data over short distances.
Limited by electrical signal interference and degradation by EMI.
Describe a serial connection. - ANSWER-Able to send data over long distances.
Nearly all LAN/WAN technologies utilize serial communications.
Describe a synchronous transmission mode. - ANSWER-It is time-based. An internal or
external clock provides the synchronization to handle this communication. Timing is
maintained regardless of presence of data.
Describe an asynchronous transmission mode. - ANSWER-There is no timing source to
control when data is sent. It utilizes start and stop bits to indicate the beginning and end
of communication (it may have 1, 1.5, or 2 stop bits for simple RS systems). The
synchronization must be re-established for every communication cycle.
Example of full duplex - ANSWER-Telephone network in which communication is
occurring between two persons who can talk and listen at the same time.
Example of half-duplex - ANSWER-A walkie-talkie sends one message at a time in both
directions.
, Example of simplex - ANSWER-Keyboard can only input, monitor can only output.
Examples of parallel and asynchronous - ANSWER-Not many communications
protocols and standards, reviewed for HPC
Examples of parallel and synchronous - ANSWER-Internal buses, printers and scanners
Examples of serial and asynchronous - ANSWER-Most "terminal" applications,
keyboard, mice, ATM, Firewire
Examples of serial and synchronous - ANSWER-T-Carrier system, SONET, frame relay,
xDSL, ISDN, USB, Firewire
Full duplex - ANSWER-Can transmit and receive simultaneously. It is used when
communication in both directions is required all the time. The capacity of the channel
must be divided in two directions, however.
Half-duplex - ANSWER-Can transmit and receive, but not at the same time. It is used
for when there is no need to communicate in both directions at the same time.
How are VLAN memberships assigned? - ANSWER-- by port
- by MAC addresses
- by network protocols
- by IP subnets (L3)
- by higher layers, such as network services (L4-L7)
How do re-transmit requests work? - ANSWER-By sequence # and ACK.
How does addressing the frame work? - ANSWER-It allows data to be sent to an
appropriate destination and responses are returned.
How does continuous ARQ work? - ANSWER-It requires the retransmission of
everything in the window from the error forward. It slides the window and sequence
numbers.
How does CSMA/CA work? - ANSWER-The devices on a WLAN must sense the
medium for energy and wait until the medium is free before sending.
How does discrete ARQ work? - ANSWER-Stop and wait
How does selective ARQ work? - ANSWER-It requires the retransmission of only the
error frame. It slides the window and sequence numbers.
How many byte is the size of the frame check sequence? - ANSWER-4 bytes
How many bytes in size is the data/pad? - ANSWER-46 - 1500 bytes
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 CLOUND. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.49. You're not tied to anything after your purchase.