| Question 1 | Which things are required when successfully testing a router configured to use a modem? (Choose all that apply.) |
| A1: | Answers B and C are correct. To attach a modem to a router, you must have an asynchronous serial interface. The modem is a DCE device and must be present. Answer A is incorrect; you can manually configure the modem, thereby bypassing the modemcap database. Answer D is incorrect; a modem must be attached to an asynchronous serial interface. |
| Question 2 | Which command do you use to create a new entry in the modemcap database? A. modemcap entry B. modemcap new C. modemcap edit D. modemcap copy
|
| A2: | Answer C is correct; modemcap edit new_entry_id is the correct syntax to create a new entry in the modemcap database. Answers A, B, and D are incorrect because there are no such commands in the Cisco IOS. |
| Question 3 | How does a modem indicate that it can be used to place a call? A. RTS B. CTS C. CD D. DSR E. DTR
|
| A3: | Answer D is correct; the modem indicates that it can place a call by sending DSR to the DTE device. Answers A and B are incorrect; DTE/DCE devices use RTS and CTS to indicate they can store data for transmission after a call is placed. Answer C is incorrect; CD indicates that a connection has been established with the other DCE device. Answer E is incorrect; DTR is sent by the DTE device (the router or computer) to indicate that it can receive any incoming calls. |
| Question 4 | Which command will set a serial interface into asynchronous mode? A. interface async B. physical-layer async C. async mode D. physical layer async
|
| A4: | Answer B is correct; the correct syntax, in interface configuration mode, to enable asynchronous communications is physical-layer async. Answer A is incorrect; interface async is the command used to enter configuration mode for a line that is already in asynchronous mode. Answer C is incorrect; there is no such IOS command. Answer D is incorrect; the correct command to place an interface in asynchronous mode requires a hyphen between physical and layer. |
| Question 5 | Which command displays the current status of all asynchronous interfaces on the system? A. show interface B. show async interface C. show line D. show interface async
|
| A5: | Answer C is correct; the show line command displays status information for all interfaces that have been placed in asynchronous mode and all other lines, such as console, aux, and Telnet. Answer A is incorrect; the show interface command displays physical characteristics of serial interfaces but does not show any information about VTY, console, or aux lines. Answers B and D are incorrect; there is no command with either syntax. |
| Question 6 | Which two of the following are error detection/correction standards for modems? (Choose two.) A. MNP 4 B. MNP 5 C. V.42bis D. LAP-M
|
| A6: | Answers A and D are correct. MNP 2-4 are public domain error detection/correction standards created by Microcom. LAP-M is an error detection/correction mechanism designed by the CCITT, which later became the ITU-T. Answer B is incorrect; MNP 5 defines data compression at a ratio of 2:1. Answer C is incorrect; V.42bis defines data compression at a ratio of 4:1. |
| Question 7 | Which of the following is the connection made by the administrator configuring the modem? |
| A7: | Answer C is correct; to configure a modem, you reverse Telnet into the modem from the router that will be controlling it. Answer A is incorrect; a forward connection happens through the modem from router to router. Answers B and D are incorrect; there are no such types of connections. |
| Question 8 | Which mode must you be in to configure the physical settings that allow a router to communicate with a modem attached to a serial interface? A. Router# B. Router(config-async)# C. Router(config-if)# D. Router(config-line)#
|
| A8: | Answer D is correct; to configure a modem, you must be in line configuration mode. Answer A is incorrect; you cannot configure the modem without being in config mode. Answer C is incorrect; interface configuration mode allows you to configure the router but not the modem. Answer B is incorrect; there is no such mode on a router. |
| Question 9 | What debug command do you issue to display the process of automatic detection of an attached modem? A. debug confmodem B. debug modemconf C. debug modemcap D. debug modem detect
|
| A9: | Answer A is correct; the only correct debug statement listed is debug confmodem. Answers B, C, and D are incorrect; there are no such debug commands. |
| Question 10 | What should happen to the router with no or low DTR signals? A. The modem should initiate a call. B. The modem should hang up. C. The modem should redial to get a cleaner line. D. The modem should answer busy.
|
| A10: | Answer B is correct; low or no DTR indicates that the DTE device cannot accept data and therefore cannot continue to participate in the call. The modem should hang up. Answer A is incorrect; of all the signals, RTS comes closest to asking the modem to initiate a call but is still not quite accurate. Answer C is incorrect; the modem will only hang up and try again if CD is low or is lost completely. Lost CD indicates that there is no longer an active connection to the other side. Redial also only happens if the router is configured to do so. Answer D is incorrect; there is no signal that can be sent to the modem to reply busy. The busy signal is generated by the phone company, not the modem. |
