Cisco 200-105 Free Practice Questions

Answer: A,E

Explanation: Collision Domains

A collision domain is an area of a single LAN where end stations contend for access to the network because all end stations are connected to a shared physical medium. If two connected devices transmit onto the media at the same time, a collision occurs. When a collision occurs, a JAM signal is sent on the network, indicating that a collision has occurred and that devices should ignore any fragmented data associated with the collision. Both sending devices back off sending their data for a random amount and then try again if the medium is free for transmission. Therefore, collisions effectively delay transmission of data, lowering the effective throughput available to a device. The more devices that are attached to a collision domain, the greater the chances of collisions; this results in lower bandwidth and performance for each device attached to the collision domain. Bridges and switches terminate the physical signal path of a collision domain, allowing you to segment separate collision domains, breaking them up into multiple smaller pieces to provide more bandwidth per user within the new collision domains formed.

Answer: C

Explanation:

Common Causes of Slow IntraVLAN and InterVLAN Connectivity

The symptoms of slow connectivity on a VLAN can be caused by multiple factors on different network layers. Commonly the network speed issue may be occurring on a lower level, but symptoms can be observed on a higher level as the problem masks itself under the term "slow VLAN". To clarify, this document defines the following new terms: "slow collision domain", "slow broadcast domain" (in other words, slow VLAN), and "slow interVLAN forwarding". These are defined in the section Three Categories of Causes, below.

In the following scenario (illustrated in the network diagram below), there is a Layer 3 (L3) switch performing interVLAN routing between the server and client VLANs. In this failure scenario, one server is connected to a switch, and the port duplex mode is configured half- duplex on the server side and full-duplex on the switch side. This misconfiguration results in a packet loss and slowness, with increased packet loss when higher traffic rates occur on the link where the server is connected. For the clients who communicate with this server, the problem looks like slow interVLAN forwarding because they do not have a problem communicating to other devices or clients on the same VLAN. The problem occurs only when communicating to the server on a different VLAN. Thus, the problem occurred on a single collision domain, but is seen as slow interVLAN forwarding.

Three Categories of Causes

The causes of slowness can be divided into three categories, as follows:

Slow Collision Domain Connectivity

Collision domain is defined as connected devices configured in a half-duplex port configuration, connected to each other or a hub. If a device is connected to a switch port and full-duplex mode is configured, such a point-to-point connection is collisionless. Slowness on such a segment still can occur for different reasons.

Slow Broadcast Domain Connectivity (Slow VLAN)

Slow broadcast domain connectivity occurs when the whole VLAN (that is, all devices on the same VLAN) experiences slowness.

Slow InterVLAN Connectivity (Slow Forwarding Between VLANs)

Slow interVLAN connectivity (slow forwarding between VLANs) occurs when there is no slowness on the local VLAN, but traffic needs to be forwarded to an alternate VLAN, and it is not forwarded at the expected rate.

Causes for Network Slowness Packet Loss

In most cases, a network is considered slow when higher-layer protocols (applications) require extended time to complete an operation that typically runs faster. That slowness is caused by the loss of some packets on the network, which causes higher-level protocols like TCP or applications to time out and initiate retransmission.

Hardware Forwarding Issues

With another type of slowness, caused by network equipment, forwarding (whether Layer 2 [L2] or L3) is performed slowly. This is due to a deviation from normal (designed) operation and switching to slow path forwarding. An example of this is when Multilayer Switching (MLS) on the switch forwards L3 packets between VLANs in the hardware, but due to misconfiguration, MLS is not functioning properly and forwarding is done by the router in

the software (which drops the interVLAN forwarding rate significantly).

Answer: C

Answer: A,B

Answer: D

Explanation:

Frame-relay map ip 192.168.1.2 202 command statically defines a mapping between a network layer address and a DLCI. The broadcast option allows multicast and broadcast packets to flow across the link.

The command frame-relay map ip 192.168.1.2 202 broadcast means to mapping the distal IP 192.168.1.2 202 to the local DLCI . When the u201cbroadcastu201d keyword is included, it turns Frame Relay network as a broadcast network, which can forward broadcasts. http://www.cisco.com/en/US/docs/ios/wan/command/reference/wan_f2.html#wp1012264

Answer: A

Explanation:

"If an access port receives a packet with an 802.1Q tag in the header other than the access VLAN value, that port drops the packet without learning its MAC source address."

Answer: D

Explanation:

Ping is a tool that helps to verify IP-level connectivity; PathPing is a tool that detects packet loss over multiple-hop trips. When troubleshooting, the ping command is used to send an ICMP Echo Request to a target host name or IP address. Use Ping whenever you want to verify that a host computer can send IP packets to a destination host. You can also use the Ping tool to isolate network hardware problems and incompatible configurations.

If you call ipconfig /all and receive a response, there is no need to ping the loopback address and your own IP address u2014 Ipconfig has already done so in order to generate the report.

It is best to verify that a route exists between the local computer and a network host by first using ping and the IP address of the network host to which you want to connect. The command syntax is:

ping < IP address >

Perform the following steps when using Ping:

u2711 Ping the loopback address to verify that TCP/IP is installed and configured correctly on the local computer.

ping 127.0.0.1

If the loopback step fails, the IP stack is not responding. This might be because the TCP drivers are corrupted, the network adapter might not be working, or another service is interfering with IP.

u2711 Ping the IP address of the local computer to verify that it was added to the network

correctly. Note that if the routing table is correct, this simply forwards the packet to the loopback address of 127.0.0.1.

ping < IP address of local host >

u2711 Ping the IP address of the default gateway to verify that the default gateway is functioning and that you can communicate with a local host on the local network.

ping < IP address of default gateway >

u2711 Ping the IP address of a remote host to verify that you can communicate through a router.

ping < IP address of remote host >

u2711 Ping the host name of a remote host to verify that you can resolve a remote host name.

ping < Host name of remote host >

u2711 Run a PathPing analysis to a remote host to verify that the routers on the way to

the destination are operating correctly. pathping < IP address of remote host >

Answer: D

Explanation:

All the above networks can be summarized to 10.0.0.0 network but the question requires to u201crepresent the LANs in Phoenix but no additional subnetsu201d so we must summarized to

10.4.0.0 network. The Phoenix router has 4 subnets so we need to u201cmove leftu201d 2 bits of u201c/24-> /22 is the best choice - D is correct.

Answer: A

Explanation:

Cisco supports two Frame Relay encapsulation types: the Cisco encapsulation and the

IETF Frame Relay encapsulation, which is in conformance with RFC 1490 and RFC 2427. The former is often used to connect two Cisco routers while the latter is used to connect a Cisco router to a non-Cisco router. You can test with your Cisco router when typing the command Router(config-if)#encapsulation frame-relay ? on a WAN link.

Note: Three LMI options are supported by Cisco routers are ansi, Cisco, and Q933a. They represent the ANSI Annex D, Cisco, and ITU Q933-A (Annex A) LMI types, respectively. HDLC is a WAN protocol same as Frame-Relay and PPP so it is not a Frame Relay encapsulation type.

Answer: B,C,E