2B Flashcards
___ ___ are nothing more than classifying how networks distribute their total bandwidth to their connected users.
Bandwidth allocations
There are four types of bandwidth allocations—
Conventional, Demand Assigned, Dynamic, and Time of Day Restriction.
This bandwidth allocation has a fixed amount of bandwidth that is
common to all users.
Conventional
Conventional is the most predictable, but the least efficient, in managing bandwidth because…?
- Each channel is dedicated to a specific user, even if the user is not actively transmitting data. Therefore, when a user’s channel becomes inactive, it is wasted bandwidth.
- Also, if a user decides to use a lesser amount of bandwidth (sends data instead of voice), the remaining bandwidth is also wasted.
This bandwidth allocation is based on the individual bandwidth
needs of the user.
Demand Assigned
Demand Assigned manages the bandwidth more efficiently than conventional. It does not dedicate any of its channels to a specific user. Instead, bandwidth is allocated…?
on an as needed basis in the exact amount needed
The biggest limitation of demand assigned is that…? Thus transmissions from that node will be slower until enough bandwidth becomes available.
available bandwidth may not be enough for the next user
When the combined data rates of the input users exceed the total bandwidth that a network can support, the system is said to be…?
dynamically allocating bandwidth
These restrictions ensure enough bandwidth is set aside for a specific date and time of the day on a priority basis.
Time-of-Day
A ___ is formed when at least two users communicate with each other by exchanging voice, data, or message traffic across some form of transmission line or media.
network
The most popular example of a network is the ___.
Internet
How a node is designed is driven by a set of standards (protocols) developed by the…?
Electronics Industries Association (EIA)
These standards determine how computers communicate with each
other across a network.
EIA
EIA standards are primarily based on ___ between nodes and the data rate at which the node needs to transmit. They also mandate the use of certain cables and connectors as well as modems or line drivers.
distance
If the data travels beyond the minimum distance set forth by each
EIA standard, then a ___ is required.
modem
___ will maintain the integrity of the transmitted data by converting it to an analog signal before transmission to prevent signal deterioration.
Modems
Developed in 1962, the ___ is the oldest standard developed for serial communications between modems and terminals.
EIA-232
Formerly known as RS-232C, it provides compatibility between
various communications devices such as modems and computers and specific serial connections between the computers and their peripheral devices like printers and displays.
EIA-232C
The military equivalent of EIA–232C is…?
Military Standard (MIL- STD) 188C.
The EIA–232C specification limits direct wire connections to __ feet for data transmission rates of 56 Kbps.
50
The EIA-232C specifications for data rates of 9.6 Kbps, the direct wire limit is ___ feet.
500 to 5,000 ft
What do line drivers/receivers do?
Extend the distances the data can travel.
RS232C connections are seldom used to connect ___ which are separated by a great distance.
terminals
___was created alongside the EIA–232 standard and is considered by the EIA as the computer or user node on both sides of a network.
Data Terminal Equipment (DTE)
It is the source and destination of the data that is sent across a transmission medium to the distant end node.
DTE
DTE is any device that exists at…?
the end of a data chain
What are some examples of DTE?
Printers, servers, and gaming consoles.
___ was also created alongside the EIA–232 standard.
Data Communications Equipment (DCE)
It is referred to by the EIA as the modem on both sides of a network.
DCE
___ is any device that connects two DTE devices together using serial cables.
DCE
What are some examples of DCE?
Channel Service Units (CSU) and Digital Services Units (DSU)
It establishes, maintains, and terminates a data transfer. Thus, ___ also includes the
specific transmission medium that the data travels across. ___ also converts, or codes, signals for communications between DTE and data circuits.
DCE