1. Which of the following describes the roles of devices in a WAN? (Choose
• A CSU/DSU terminates a digital local loop.
A modem terminates a digital local loop.
A CSU/DSU terminates an analog local loop.
• A modem terminates an analog local loop.
• A router is commonly considered a DTE device.
A router is commonly considered a DCE device.
2. What value in the address field of a Frame Relay header identifies the
destination of the frame?
3. The serial PPP link between the Left and Right routers is configured as shown
in the diagram. Which configuration issue explains why the link is unable to
establish a PPP session?
The IP addresses must be on different subnets.
• The usernames are misconfigured.
The passwords must be different for the CHAP authentication.
The clock rate must be 56000.
The clock rate is configured on the wrong end of the link.
Interface serial 0/0 on Left must connect to interface serial 0/1 on Right.
4. The output of the show interfaces serial 0/0 command for a frame-relay
connection indicates that the serial line is up but the line protocol is down. What
are possible causes for this? (Choose two.)
• There is an LMI-type mismatch between the Frame Relay switch and the
There is no clock present on the serial interface.
The interface is shut down.
RARP is not functioning on the router.
• The cable is disconnected.
5. Which statements are correct about the point in the network where the
responsibility of the service provider ends? (Choose three.)
• The International point is on the customer side of the network terminating
• The United States point is at the interface of the customer-provided equipment
and the local loop.
The responsibility for this point is controlled by IANA.
• The point is called the demarcation point.
The point is typically located at the service provider's central office.
The point is located between the customer's local area netw