Networking Fundamentals Flashcards
OSI Layer 1
The physical layer
OSI Layer 2
The data link layer
OSI Layer 3
The network layer
OSI Layer 4
The transport layer
OSI Layer 5
The session layer
OSI Layer 6
The presentation layer
OSI Layer 7
The application layer
This layer uses binary expressions to represent data
Layer 1: The physical layer
Groups of binary bits grouped together is called
A Protocol Data Unit (PDU)
The word ‘Packet’ is used in lieu of
Protocol Data Unit (PDU)
This layer uses frames to represent data
Layer 2: The data link layer
This layer uses packets to represent data
Layer 3: The network layer
This layer uses segments to represent data
Layer 4: The transport layer
The name of the approach that uses voltage on a copper wire or the presence/absence of light on a fiber-optic cable to render a 1 or a 0 is
Current State Modulation
Bus, Ring and Star topologies are associate with which layer of the OSI model?
Layer 1: The physical layer
This approach synchronizes the internal clocks of both the sender and the receiver to ensure that they agree on when bits begin and end. A common approach to make this synchronization happen is to use an external clock (for example, a clock given by a service provider). The sender and receiver then reference this external clock.
Synchronous
With this approach, a sender states that it is about to
start transmitting by sending a start bit to the receiver. When the receiver sees this, it starts its own internal clock to measure the next bits. After
the sender transmits its data, it sends a stop bit to say that it has finished
its transmission
Asynchronous
Divide the bandwidth available on a medium (for example, copper or fiber-optic cabling) into different channels.
Broadband
Uses all the available frequencies on a medium to send data. i.e. Ethernet
Baseband
Allows multiple communications sessions to share the same physical medium. i.e. Cable TV
Multiplexing strategy
Supports different communication sessions on the same physical medium by causing the sessions to take turns as a time slot.
Time-division multiplexing (TDM)
To make a more efficient use of available bandwidth, this protocol dynamically assigns time slots to communication sessions on an as-needed basis.
Statistical time-division multiplexing (StatTDM)
Divides a medium’s frequency range into channels, and different communication sessions send their data over different channels. This approach to bandwidth usage is called broadband.
Frequency-division multiplexing (FDM)
Packaging data into frames and transmitting those frames occurs on what OSI layer?
Layer 2: The data link layer
Which OSI layer uniquely finds network devices with an address
Layer 2: The data link layer
