Explanation:
You should issue the clock rate command on the DCE end for the connection to function. The clock rate is set on the Data Circuit-terminating Equipment (DCE) device. DCE is also known as Data Communications Equipment.

The DCE terminates a physical WAN connection, provides clocking and synchronization of a connection between two locations, and connects to a DTE. The DCE category includes equipment such as CSU/DSUs, NT1s, and modems. In the real world, the clock rate is provided by the CSU/DSU end at the telcom provider. In a lab, you must instruct the DCE end to provide a clock rate.

The DTE is an end user device, such as a router or a PC, which connects to the WAN via the DCE device.

You would not issue the bandwidth command. This command is used to inform the router of the bandwidth of the connection for purposes of calculating best routes to locations where multiple routes exist. It is not necessary for the link described to function.

You should not issue the no clock rate command. This command is used to remove any previous settings implemented with the clock rate command. You would not issue the no bandwidth command. This command is used to remove any previous settings implemented with the bandwidth command

Explanation:
Spanning Tree Protocol (STP) is a Layer 2 protocol used in LANs to maintain a loop-free network topology by recognizing physical redundancy in the network and logically blocking one or more redundant ports.

An example of switch redundancy is shown in the diagram below. The connection from SW4 to SW2, while providing beneficial redundancy, introduces the possibility of a switching loop.

STP probes the network at regular intervals to identify the failure or addition of a link, switch, or bridge. In the case of any topology changes, STP reconfigures switch ports to prevent loops. The end result is one active Layer 2 path through the switch network.

STP is not used for management of Virtual Local Area Networks (VLANs). VLAN Trunking Protocol (VTP) simplifies the management of VLANs by propagating configuration information throughout the switching fabric whenever changes are made. In the absence of VTP, switch VLAN information would have to be configured manually.

STP is not used to load-balance traffic across different redundant paths available in a topology. Load balancing allows a router to use multiple paths to a destination network. Routing protocols, Routing Information Protocol (RIP), RIPv2, Interior Gateway Routing Protocol (IGRP), Enhanced IGRP (EIGRP), and Open Shortest Path First (OSPF) support load balancing. Similarly, multiple links can be combined in a faster single link in switches. This can be achieved with the Fast EtherChannel or Gigabit EtherChannel features of Cisco switches.

STP does not prevent forwarding of unnecessary broadcast traffic on trunk links. This is achieved by manually configuring VLANs allowed on the trunk, or through VTP pruning.

Explanation:
The route with a C next to it is a directly connected route and has an administrative distance of 0, which means it will be preferred over any routes with a larger value for administrative distance. Each routing protocol has a default administrative distance assigned. Administrative distance is used by the router to determine the preferred route when a route is learned from different routing protocols. This process can be manipulated by the administrator by using the distance command to alter the default assignments.

It is significant to note that routers with no static routes and no routing protocols enabled will populate all directly connected routes to the routing table with no action on the part of the administrator. Routes that are NOT directly connected will not be in the routing table unless one of two things occurs:

– A static route is created by the administrator
– A routing protocol is enabled that allows the router to learn about the network and its route from another router running the same routing protocol

For example, in the diagram below, R3 will have routes to the 192.168.3.0/24 ,192.168.1.0/24 and the 192.168.0.0/24 networks in its routing table by default. It will only have routes to the 192.168.2.0/24, 192.168.5.0/24, and 192.168.6.0/24 networks if a routing protocol is used or if an administrator creates static routes for each network.

When a packet is received by a router interface, the router de-encapsulates the frame or removes the layer two information (MAC data for Ethernet or DLCIs for frame relay) and then performs a lookup for the network ID of the network in which the destination IP address resides. When multiple routes exist, it will choose the one with the lowest administrative distance. The router only places the route with the lowest distance in the table.

The route with an R next to it is a route learned from Routing Information Protocol (RIP). It has a default administrative distance of 120, so it will not prefer over a directly connected route.

The route with an S next to it is a static route or one configured manually. It has an administrative distance of 1, so it will not be preferred over a directly connected route.

The route with an I next to it is a route learned from Internal Gateway Routing Protocol (IGRP). It has an administrative distance of 100, so it will not be preferred over a directly connected route.

Explanation:
The command show standby can be used to display the virtual MAC address for HSRP groups of which a switch is a member. This command displays information about HSRP on all configured interfaces and for all HSRP groups. It also displays hello timer information and the expiration timer for the standby switch. The standby switch will take over as the active switch if the timer expires before it hears a heartbeat from the active switch.

The command show standby brief can be used to view summary information about HSRP groups of which the switch is a member. This information includes the group number, priority, state, active device address, standby address, and group address. It does not include the virtual MAC address.

The commands show standby mac and show hsrp mac are invalid due to incorrect syntax.

Explanation:
The upper half of the output provides information about the root bridge. It indicates that the root bridge has a bridge priority of 24586 and a MAC address of
0015.63f6.b700. The bottom half of the output pertains to the current switch, and indicates that this switch has a bridge priority of 32778 and a MAC address of 000f.f794.3d00.

The value of the switch bridge priority is arrived at by adding the configured priority of 32768, which is indicated by the line priority 32768 sys-id-ext 10, to the VLAN ID of 10. Because 32768 is the default bridge priority for STP, this switch is set to the default priority for STP.

The priority of this switch is 32778. The bridge priority is arrived at by adding the configured priority of 32768 to the VLAN ID of 10.

This switch is not the root bridge, as indicated by the differences in priorities and MAC addresses between the root ID and the bridge ID output. If this were the root bridge, the MAC addresses and priority values would be the same in both the Root ID and the Bridge ID sections.

Finally, when a switch is using RSTP, as indicated by the output Spanning tree enabled protocol rstp, all ports will be in a state of discarding, learning, or forwarding, with all designated ports in a forwarding state. When RSTP has converged, all ports will be in either the discarding or forwarding states.

Explanation:
When two routes have been learned by OSPF to same network, the best route will be chosen based on lowest cost. Cost is the metric used in OSPF to choose the best route from all candidate routes learned through OSPF.

Administrative distance is a measure of the trustworthiness of the routing information source. It is a value used by a router to choose between multiple known routes that have been learned from different routing sources, such as different routing protocols. When routes are learned from the same routing protocol, their administrative distance will be equal, and the router will then choose the route with the lowest metric value of the routing protocol. In this case, that metric is the OSPF cost.

The composite metric is the metric used by EIGRP to choose a route when multiple routes have been learned by EIGRP. Hop count is the metric used by RIP to choose a route when multiple routes have been learned by RIP.

Explanation:
OSPF will perform an election for a designated router (DR) and backup designated router (BDR) on every multi-access network segment. Multi-access segments are defined as segments where more than two hosts can reach each other directly, such as a shared Ethernet segment (broadcast multi-access) or Frame Relay (non-broadcast multi-access, or NBMA).

DR and BDR elections do not occur on point-to-point or point-to-multipoint segments. Point-to-point and point-to-multipoint segments are not considered multi- access segments. OSPF routers on these network types will establish an adjacency without a DR/BDR election.

Explanation:
The extended ping Cisco IOS utility, which is issued with no address specified, can be issued on a router to test connectivity between two remote routers. The ping utility uses Internet Control Messaging Protocol (ICMP) packets. An ICMP echo request is sent to the destination host. Upon its receipt, the destination host responds to the sending host with an ICMP echo reply. When the echo reply is received, the connectivity is verified.

The ping command with an address specified is incorrect because you when you issue this command you will either receive a reply from the destination or a destination unreachable message. It will not prompt for additional information as shown which is what allows you to specify the endpoints for the ping.

The traceroute command is not correct for this scenario because this command traces the path between the host issuing the command and the target network. The tracert command is not a Cisco IOS command, but a Microsoft command.