Data Communications And Computer Networks – Flashcards
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means that users can specify telephone numbers that are allowed to get through
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Call filtering
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means that a user calling into a company telephone system provides some form of data by speaking into the telephone, and a database query is performed using this spoken information.
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Integrated voice recognition and response
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After the 1984's Modified Final Judgment, the long-distance telephone companies became known as
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interexchange carriers (IECs or IXCs)
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The local loop commonly consists of either four or ____ wires
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eight
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Because DSL is an always-on connection, it uses a ____ circuit instead of a switched circuit
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permanent
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means that users utilize a single desktop application to send and receive e-mail, voice mail, and fax
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Unified messaging
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is a packet-switched network that was designed for transmitting data over fixed lines
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Frame relay
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means that users have the ability to control a call—for example, set up a conference call—without being a part of it
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Third-party call control
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is capable of sending traffic that may experience bursts of data, but there are no promises as to when the data may be sent
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Unspecified bit rate (UBR)
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The telephone network consists of two basic types of telephone lines: a subscriber loop, or standard telephone line, and a
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trunk
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is the most expensive ATM class of service
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Constant bit rate (CBR)
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As long as a telephone call remains within a LATA (a(n) ____ call), the telephone call is local and is handled by a local telephone company
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intraLATA
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The Telecommunications Act of 1996 mandated that the existing local telephone companies, now called ____, must give CLECs access to their telephone lines
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incumbent local exchange carriers (ILECs)
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handles all in-house calls and places calls onto outside telephone lines
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private branch exchange (PBXs)
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MPLS and VPNs continue to replace which long-distance data services?
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frame relay and ATM
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The designation layer ____ protocol means that frame relay technology is only one part of a network application and resides at the data link layer
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2
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The ____ standard is a 56,000-bps dial-up modem standard approved by a standards-making organization rather than a single company
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V.90
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is the earliest form of DSL.
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High bit-rate DSL (HDSL)
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A ____ service is an all-digital connection that can transfer either voice or data at speeds up to 1.544 Mbps
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T-1
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A(n) ____ is a service from local telephone companies in which up-to-date telephone facilities at the telephone company's central (local) office are offered to business users, so that they don't need to purchase their own facilities.
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central office exchange service
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On the other end of the local loop is the local telephone company's
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central office
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are permanent direct connections between two specified points
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Tie lines
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is a packet-switched network that was designed for transmitting data over fixed lines
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Frame relay
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Digital subscriber line comes in a variety of formats. Often collectively referred to as
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xDS
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Before ATM can transfer any data, you must first create a logical connection called a
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virtual channel connection (VCC)
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A(n) ____ connection has a faster downstream transmission speed than its upstream speed
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asymmetric
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is a format in which the transfer rate can vary, depending on noise levels within the telephone line's local loop
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Rate-adaptive DSL (RADSL)
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means that different icons on a computer screen represent common PBX functions such as call hold, call transfer, and call conferencing, making the system easier for operators to use.
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PBX graphic user interface
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The ____ allows the customer to exceed the committed information rate by a fixed amount for brief moments of time
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burst rate
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A(n) ____ connection is one in which the transfer speeds in both directions are equal
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symmetric
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When a VCC transmits network management and routing signals, it is called the
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network-network interface
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is a popular format that transmits the downstream data at a faster rate than the upstream rate
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Asymmetric digital subscriber line (ADSL)
