A+ Network Review 2/2
__ WANs are the most fault-tolerant type of WAN because they provide multiple routes for data to follow between any two points.
The __ encompasses the entire telephone system, from the wires that enter homes and businesses to the network centers.
A(n)__ is the place where a telephone company terminates lines and switches calls between different locations.
CO (Central Office)
A__ connection is one in which a user connects her computer, via modem, to a distant network and stays connected for a finite period of time.
The portion of the PSTN that connects any residence or business to the nearest CO is known as the ___.
__means that a telephone company connects residential users to its network with fiber-optic cable.
PON (Passive Optical Network)
__ is an updated, digital version of x.25 that also relies on packet switching.
In a process called__, two 64-kbps ISDN B channels can be combined to achieve an effective throughput of 128 Kbps
A __ converts digital signals into analog signals for use with ISDN phones and other analog devices.
ISDN PRI uses ___ B channels and one 64-Kbps D channel.
The speed of a T-carrier depends on its __ level.
At the customer's demarcation point, either inside or outside the building, RJ-48 connectors terminate in a __.
Broadband cable requires many subscribers to share the same local line, thus raising concerns about __ and actual (versus theoretical) throughput.
What sets ATM apart from Ethernet is its __ size.
SONET's extraordinary__ results from its use of a double-ring topology over fiber-optic cable.
The data rate of a particular SONET ring is indicated by its __ , a rating that is internationally recognized by networking professionals and standards organizations.
OC (Optical Carrier) level
In wireless communication, to exchange information, two antennas must be tuned to the same___.
A directional antenna issues wireless signals along a(n)__ direction.
In__,a wireless signal splits into secondary waves,when it encounters an obstruction.
___is a significant problem for a wireless communications because the atmosphere is saturated with electromagnetic waves.
In __ wireless systems, the transmitting antenna focuses its energy directly toward the receiving antenna which results in a point to point link.
In the case of connecting two WLANs, access points could be as far as__feet apart.
In__scanning, the station transmits a special frame, known as a probe, on all available channels within its frequency range.
A unique characteristic of the 802.11 data frame is its __ field.
The average geographic range for an 802.11 a antenna is __meters.
___may use either the 2.4-GHz or 5-GHz frequency range.
__is an 802.11n feature that allows two adjacent 20-MHz channels to be combined to make a 40-MHz channel.
__is an 802.11n network feature allowing the combination of multiple frames into one larger frame.
__is a command-line function for viewing and setting wireless interface parameters and it is common to nearly all versions of Linux and Unix.
If intermittent and difficult to diagnose wireless communication errors occur, __ might be the culprit.
Most satellites circle the Earth __ miles above the equator in a geosynchronous orbit.
__satellites are the type used by the most popular satellites data service providers.
Geosynchronous earth orbiting
Clients are able to exchange signals with satellites as long as they have a ___path.
To establish a satellite internet connection, each subscriber must have a __.