CCNA 4 Module 2 v.4

Which two statements are true regarding time-division multiplexing (TDM)? (Choose two.)
	It allows information from multiple channels to be allocated bandwidth on a multiple wires.
	Multiple sources can transmit over a single channel.
	Original data streams must be reconstructed at the destination.
	TDM relies on Layer 3 protocols to operate.
	TDM methods vary depending on the Layer 2 protocol used.

What does the demarcation point represent in data communication physical circuits?
	DTE/DCE interface on the device connecting to the Internet
	location of the firewall or router
	physical point at which the public network ends and the private customer network begins
	tag assigned to the physical block where a cross-connect occurs

Which serial communications DTE/DCE interface standard is used to provide high-speed connectivity of up to 52 Mbps between LANs and is found on many high-end Cisco routers?
	EIA/TIA 232 (RS-232)
	ITU V.35
	HSSI
	EIA/TIA 422 (RS-422)
	EIA/TIA 423 (RS-423)

What is the reason why parallel data communications is not feasible over long transmission lengths?
	crosstalk between wires and clock skew
	error checking not possible
	transmission rate is too low
	too much attenuation

What would show interface s0/0/0 indicate if show controllers s0/0/0 indicated a cable type of unknown?
	serial 0/0/0 is down, line protocol is down
	serial 0/0/0 is up, line protocol is down
	serial 0/0/0 is up, line protocol is up (looped)
	serial 0/0/0 is up, line protocol is down (disabled)
	serial 0/0/0 is administratively down, line protocol is down

Which three statements are correct about HDLC encapsulation? (Choose three.)
	HDLC supports PAP and CHAP authentication.
	HDLC implementation in Cisco routers is proprietary.
	HDLC specifies a data encapsulation method on synchronous serial links using frame characters and checksums
	HDLC is the default serial interface encapsulation on Cisco routers.
	HDLC and PPP are compatible.
	HDLC does not support CDP.

Refer to the exhibit. Which series of statements accurately describes the PPP link establishment process for these routers?
	LCP negotiates the authentication option LCP tests link quality PAP authentication NCP negotiates Layer 3 protocol options
	LCP negotiates the compression and authentication options LCP tests link quality CHAP authentication NCP negotiates Layer 3 protocol options
	LCP tests the link quality LCP negotiates compression and authentication options CHAP authentication NCP negotiates Layer 3 protocol options
	CHAP authentication LCP tests link quality LCP negotiates compression options NCP negotiates Layer 3 protocol options
	LCP negotiates the compression and authentication options NCP negotiates Layer 3 protocol options LCP tests link quality CHAP authentication

Which three statements are true regarding LCP? (Choose three.)
	It is responsible for negotiating link establishment.
	It negotiates options for Layer 3 protocols running over PPP.
	It uses MD5 encryption while negotiating link establishment parameters.
	It terminates the link upon user request or the expiration of an inactivity timer.
	It can test the link to determine if link quality is sufficient to bring up the link.
	It monitors the link for congestion and dynamically adjusts the acceptable window size.

Which two options can LCP negotiate? (Choose two.)
	link quality
	authentication
	dynamic flow control
	compression and network layer address for IP
	connection-oriented or connectionless communication methods

Which advantage does the multilink option provide when using PPP?
	Data transmission has load balancing possibilities.
	Interfaces can be configured using both HDLC and PPP.
	More than one authentication method can be used.
	More than one compression protocol can be configured.

What function do Network Control Protocols provide for a PPP connection?
	to establish and terminate data links
	error detection
	to manage network congestion and to allow quality testing of the link
	to allow multiple Layer 3 protocols to operate over the same physical link
	to provide authentication capabilities to PPP

Refer to the exhibit. On the basis of the show interface Serial0/0/0 output, how many NCP sessions have been established?
	one
	two
	three
	four

Refer to the exhibit. According to the the provided router output, which statement is true regarding PPP operation?
	Only the link-establishment phase completed successfully.
	Only the network-layer phase completed successfully.
	Neither the link-establishment phase nor the the network-layer phase completed successfully.
	Both the link-establishment and network-layer phase completed successfully.

Refer to the exhibit. Which two items were negotiated during the PPP session shown in the debug output? (Choose two.)
	Challenge Handshake Authentication Protocol
	Password Authentication Protocol
	compression
	link quality
	error detection

Which three statements correctly describe PPP authentication? (Choose three.)
	PAP sends passwords in clear text.
	PAP uses a 3-way handshake to establish a link.
	PAP provides protection from repeated trial-and-error attacks.
	CHAP uses a 2-way handshake to establish a link.
	CHAP uses a challenge/response that is based on the MD5 hash algorithm.
	CHAP uses repeated challenges for verification.

Which authentication protocol can be spoofed to allow playback attacks?
	MD5
	CHAP
	PAP
	NCP

Refer to the exhibit. What statement is true regarding the output shown?
	LCP is in the process of negotiating a link.
	LCP and NCP are waiting for CHAP authentication to complete.
	LCP negotiation has been successful, but NCP negotiation is in progress.
	Data is able to flow across this link.

Refer to the exhibit. What statement is true regarding the output shown?
	NCP has successfully negotiated.
	The PAP passwords did not match, so the routers are trying CHAP authentication.
	One router has suggested PAP authentication, and the other has accepted authentication but suggested CHAP authentication.
	One router can only use PAP authentication while the other router can only use CHAP, so the connection has been rejected.

Refer to the exhibit. Which two statements are true regarding the output shown? (Choose two.)
	LCP negotiation has been successful.
	The router has agreed on IP parameters.
	The router is negotiating IP compression options.
	The router is requesting an IP address from its peer.
	The router has accepted IP but not the suggested IP options.

Refer to the exhibit. Which two statements are true about this configuration? (Choose two.)
	Authentication will fail between these routers.
	Each router authenticates its neighbor against the username and password that are configured in the local database.
	The default encapsulation type is configured on these routers.
	NCP negotiates for IP to use predictor compression.
	If there is more than a 20% error rate on the line, then LCP will take the line down.

Which statement describes parallel data communications?
	Digital data is broken into 8-bit chunks (bytes) and transmitted from one entity to another bit by bit.
	Digital data that is transmitted over a parallel connection is not affected by clock skew or crosstalk.
	Digital data is transmitted from one entity to another via the use of a bus that consists of multiple wires, each carrying one bit of the data sample.
	Digital data is transmitted via the use of two loops of wire, one in each direction.