1,According to Cisco:PPP, described in RFC 1661,encapsulates network layer protocol information over point-to-point links. You can configure PPP on the following types of physical interfaces:
Asynchronous serial
HSSI
ISDN
Synchronous serial
By enabling PPP encapsulation on physical interfaces, PPP can also be in effect on calls placed by the dialer interfaces that use the physical interfaces.
2,You want your router to be able to dynamically fluctuate at the rate at which it sends packets, depending on the BECNs it receives. What command will you use for this?
answer:frame-relay adaptive-shaping becn
3,Which of the following are valid functions that chat scripts perform?
answer:modem configuration
dialing and remote login
failure detection
4,When configuring X.25 to use a PVC, you must ensure that no traffic is sent toward a remote terminal server between the time the X.25 map comand is issued and the time that X.25 pvc command is issued. Otherwise, the local system will create an switched virtual circuit(SVC), and then the PVC command will not be allowed. Map entries with the broadcast attribute are particularly likely to get traffic, due to routing protocol traffic. The simplest way to ensure that no traffic is sent whild configuring is to shut down the interface while configuring it for a PVC
5,What command should you use to specify RADIUS as the method of user authentication when no other method list has been defined?
answer:aaa authentication ppp default radius
6,What command should you use to display the current X25 virtual circuit parameters and statistics?
answer:show x25 vc
7,According to Cisco: Cisco's QoS software solutions include two traffic shaping tools-generic traffic shaping(GTS) and Frame Relay traffic shaping(FRTS)-to manage traffic and congestion on the network. GTS provides a mechanism to control the traffic flow on a particular interface. It reduces outbound traffic flow to avoid congestion by constraining specified traffic to a particular bit rate(also known as the token bucket approach), while queuing bursts of the specified traffic. FRTS provides parameters that are useful for managing network traffic congestion.
8,According to Cisco:Two layer 3 specifications are used for ISDN signaling: ITU-T(formerly CCITT)I.450 (also known as ITU-T Q.930) and ITU-T I.451(also known as ITU-T Q.931).Together, these protocols support user-to-user, circuit-switched, and packet-switched connections. A variety of call-establishment, call-termination, information,and miscellaneous messages are specified, including SETUP, CONNECT,RELEASE, USER INFORMATION, CANCEL, STATUS, and DISCONNECT. These messages are functionally similar to those provided by the X.25 protocol
9,According to the technical documentation at CCO:X.21 bis is a physical layer protocol used in X.25 that defines the electrical and mechanical procedures for using the physical medium. X.21 bis handles the activation and deactivation of the physical medium connecting DTE and DCE devices. It supports point-to-point connections, speeds up to 19.2 kbps, and synchronous, full-duplex transmission over four-wire media
10,According to the technical documentation at CCO:
The LAPD Flag and Control fields are identical to those of HDLC. The LAPD Address field can be either 1 or 2 bytes long .If the extended address bit of the first byte is set, the address is 1 byte; if it is not set, the address is 2 bytes. The first Address-field byte contains the service access point identifier(SAPI), which identifies the portal at which LAPD services are provided to Layer 3
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