For Dummies CCNA Certification All-In-One 978-0-470-48962-8 Manual De Usuario
Los códigos de productos
978-0-470-48962-8
Wide-Area Networking Basics
Answers
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D, E. DCE and CSU/DSU. Data communications equipment (DCE), also referred
to as a channel service unit/data service unit (CSU/DSU), controls the timing
synchronization for WAN devices. Review “Data terminal equipment (DTE) and
data communications equipment (DCE).”
to as a channel service unit/data service unit (CSU/DSU), controls the timing
synchronization for WAN devices. Review “Data terminal equipment (DTE) and
data communications equipment (DCE).”
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B. A 60-pin DCE-to-DTE crossover cable is used to establish a simulated DCE-to-
DTE environment using the serial interface between Cisco routers. See “Cisco
serial interfaces” and “Introducing Cable Connections.”
DTE environment using the serial interface between Cisco routers. See “Cisco
serial interfaces” and “Introducing Cable Connections.”
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D. Customer premises equipment (CPE) connects to equipment provided by
the telephone company at the demarcation point. Refer to “Data terminal
equipment (DTE) and data communications equipment (DCE).”
the telephone company at the demarcation point. Refer to “Data terminal
equipment (DTE) and data communications equipment (DCE).”
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C. PPPoE. Many Internet service providers use PPPoE to authenticate customers
using a username and password over dialup connections. Take a look at
“Encapsulation Types.”
using a username and password over dialup connections. Take a look at
“Encapsulation Types.”
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A. ISDN. ISDN BRI (Basic Rate Interface) is a service using two 64-Kbps bearer
channels (2B) plus one 16-Kbps data channel (D) used for clocking, and is called
“out-of-band” signaling. Read “Introducing Cable Connections.”
channels (2B) plus one 16-Kbps data channel (D) used for clocking, and is called
“out-of-band” signaling. Read “Introducing Cable Connections.”
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C. SLIP. Serial Line Internet Protocol is a very simplistic, nonstandard protocol
used to frame and transmit IP datagrams over serial connections. See
“Encapsulation Types.”
used to frame and transmit IP datagrams over serial connections. See
“Encapsulation Types.”
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B. HSSI. High-Speed Serial Interface (HSSI) is a proprietary smart-serial DTE/
DCE interface that uses a male, subminiature 50-pin connector with a maximum
cable length of 50 feet. Examine “Cisco serial interfaces.”
DCE interface that uses a male, subminiature 50-pin connector with a maximum
cable length of 50 feet. Examine “Cisco serial interfaces.”
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B, E. POTS and ISDN. The two types of serial circuit-switched connections are
asynchronous plain old telephone system (POTS) dialup and synchronous
Integrated Services Digital Network (ISDN). Look over “Connection Types.”
asynchronous plain old telephone system (POTS) dialup and synchronous
Integrated Services Digital Network (ISDN). Look over “Connection Types.”
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B, D. Frame Relay and X.25 are known as packet-switched technologies and
provide higher bandwidth and cost compared to ISDN and dialup alternatives.
Check out “Connection Types.”
provide higher bandwidth and cost compared to ISDN and dialup alternatives.
Check out “Connection Types.”
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D. Dedicated leased line. A dedicated leased line establishes a permanent link
using a point-to-point serial connection, which provides guaranteed bandwidth
to remote networks. Review “Connection Types.”
using a point-to-point serial connection, which provides guaranteed bandwidth
to remote networks. Review “Connection Types.”
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C. ATM. Asynchronous Transfer Mode establishes a point-to-point cell-switched
WAN that transmits 53-byte packets called cells. Refer to “Connection Types.”
WAN that transmits 53-byte packets called cells. Refer to “Connection Types.”
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