Virtual of ccna routing and switching icnd2 200 105 official cert guide free question materials and pdf for Cisco certification for IT examinee, Real Success Guaranteed with Updated 200 105 icnd2 pdf dumps vce Materials. 100% PASS Interconnecting Cisco Networking Devices Part 2 (ICND2 v3.0) exam Today!

Q21. - (Topic 3) 

What can be done to Frame Relay to resolve split-horizon issues?(Choose two.) 

A. Disable Inverse ARP. 

B. Create a full-mesh topology. 

C. Develop multipoint subinterfaces. 

D. Configure point-to-point subinterfaces. 

E. Remove the broadcast keyword from the frame-relay map command. 

Answer: B,D 

Explanation: 

IP split horizon checking is disabled by default for Frame Relay encapsulation to allow routing updates to go in and out of the same interface. An exception is the Enhanced Interior Gateway Routing Protocol (EIGRP) for which split horizon must be explicitly disabled. Certain protocols such as AppleTalk, transparent bridging, and Internetwork Packet Exchange (IPX) cannot be supported on partially meshed networks because they require split horizon to be enabled (a packet received on an interface cannot be transmitted over the same interface, even if the packet is received and transmitted on different virtual circuits). Configuring Frame Relay subinterfaces ensures that a single physical interface is treated as multiple virtual interfaces. This capability allows you to overcome split horizon rules so packets received on one virtual interface can be forwarded to another virtual interface, even if they are configured on the same physical interface. 


Q22. - (Topic 3) 

Which Layer 2 protocol encapsulation type supports synchronous and asynchronous circuits and has built-in security mechanisms? 

A. HDLC 

B. PPP 

C. X.25 

D. Frame Relay 

Answer:

Explanation: 

High-Level Data Link Control (HDLC) - HDLC is the default encapsulation type on point-to-point, dedicated links, and circuit-switched connections. It is used typically when communicating between two Cisco devices. It is a bit-oriented synchronous data link layer protocol. Point-to-Point Protocol (PPP) - Provides router-to-router and host-to network connections over synchronous and asynchronous circuits. PPP was designed to work with several network layer protocols, such as IP, and IPX. PPP also has built in security mechanisms such as PAP and CHAP X.25/Link Access Procedure, Balanced (LAPB) - ITU-T standard that defines how connections between DTE and DCE are maintained for remote terminal access and computer communications in public data networks. X.25 specifies LAPB, a data line layer protocol. X.25 is a predecessor to Frame Relay. Frame Relay - Industry standard, switched data link layer protocol that handles multiple virtual circuits. It is a next-generation to X.25 that is streamlined to eliminate some of the time-consuming processes (such as error correction and flow control) that were employed in X.25. 


Q23. - (Topic 3) 

Users have been complaining that their Frame Relay connection to the corporate site is very slow. The network administrator suspects that the link is overloaded. Based on the partial output of the Router # show frame relay pvc command shown in the graphic, which output value indicates to the local router that traffic sent to the corporate site is experiencing congestion? 

A. DLCI=100 

B. last time PVC status changed 00:25:40 

C. in BECN packets 192 

D. in FECN packets 147 

E. in DF packets 0 

Answer:

Explanation: 

First we should grasp the concept of BECN & FECN through an example: 

Suppose Router A wants to send data to Router B through a Frame Relay network. If the network is congested, Switch 1 (a DCE device) will set the FECN bit value of that frame to 1, indicating that frame experienced congestion in the path from source to destination. This frame is forwarded to Switch 2 and to Router B (with the FECN bit = 1). Switch 1 knows that the network is congesting so it also sends frames back to Router A with BECN bit set to 1 to inform that path through the network is congested. 

In general, BECN is used on frames traveling away from the congested area to warn source devices that congestion has occurred on that path while FECN is used to alert receiving devices if the frame experiences congestion. 

BECN also informs the transmitting devices to slow down the traffic a bit until the network returns to normal state. The question asks “which output value indicates to the local router that traffic sent to the corporate site is experiencing congestion” which means it asks about the returned parameter which indicates congestion ->BECN. 


Q24. - (Topic 2) 

Refer to the exhibit. 

The Lakeside Company has the internetwork in the exhibit. The administrator would like to reduce the size of the routing table on the Central router. Which partial routing table entry in the Central router represents a route summary that represents the LANs in Phoenix but no additional subnets? 

A. 10.0.0.0/22 is subnetted, 1 subnets D 10.0.0.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1 

B. 10.0.0.0/28 is subnetted, 1 subnets D 10.2.0.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1 

C. 10.0.0.0/30 is subnetted, 1 subnets D 10.2.2.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1 

D. 10.0.0.0/22 is subnetted, 1 subnets D 10.4.0.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1 

E. 10.0.0.0/28 is subnetted, 1 subnets D 10.4.4.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1 

F. 10.0.0.0/30 is subnetted, 1 subnets D 10.4.4.4 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1 

Answer:

Explanation: 

All the above networks can be summarized to 10.0.0.0 network but the question requires to “represent the LANs in Phoenix but no additional subnets” so we must summarized to 

10.4.0.0 network. The Phoenix router has 4 subnets so we need to “move left” 2 bits of “/24-> /22 is the best choice - D is correct. 


Q25. - (Topic 3) 

What occurs on a Frame Relay network when the CIR is exceeded? 

A. All TCP traffic is marked discard eligible. 

B. All UDP traffic is marked discard eligible and a BECN is sent. 

C. All TCP traffic is marked discard eligible and a BECN is sent. 

D. All traffic exceeding the CIR is marked discard eligible. 

Answer:

Explanation: 

Committed information rate (CIR): The minimum guaranteed data transfer rate agreed to by the Frame Relay switch. Frames that are sent in excess of the CIR are marked as discard eligible (DE) which means they can be dropped if the congestion occurs within the Frame Relay network. Note: In the Frame Relay frame format, there is a bit called Discard eligible (DE) bit that is used to identify frames that are first to be dropped when the CIR is exceeded. 


Q26. - (Topic 3) 

A network administrator needs to configure a serial link between the main office and a remote location. The router at the remote office is a non-Cisco router. How should the network administrator configure the serial interface of the main office router to make the connection? 

A. Main(config)# interface serial 0/0 Main(config-if)# ip address 172.16.1.1 255.255.255.252 Main(config-if)# no shut 

B. Main(config)# interface serial 0/0 Main(config-if)# ip address 172.16.1.1 255.255.255.252 Main(config-if)# encapsulation ppp Main(config-if)# no shut 

C. Main(config)# interface serial 0/0 Main(config-if)# ip address 172.16.1.1 255.255.255.252 Main(config-if)# encapsulation frame-relay Main(config-if)# authentication chap Main(config-if)# no shut 

D. Main(config)# interface serial 0/0 Main(config-if)#ip address 172.16.1.1 255.255.255.252 Main(config-if)#encapsulation ietf Main(config-if)# no shut 

Answer:

Explanation: 

Cisco High-Level Data Link Controller (HDLC) is the Cisco proprietary protocol for sending data over synchronous serial links using HDLC. So HDLC runs only in Cisco router. PPP is not proprietary protocol it's a open source every cisco router and non-cisco router understand the PPP protocol.So we need to configure the PPP protocol if connection is between cisco and non-cisco router. 


Q27. - (Topic 1) 

Which two of these statements regarding RSTP are correct? (Choose two.) 

A. RSTP cannot operate with PVST+. 

B. RSTP defines new port roles. 

C. RSTP defines no new port states. 

D. RSTP is a proprietary implementation of IEEE 802.1D STP. 

E. RSTP is compatible with the original IEEE 802.1D STP. 

Answer: B,E 

Explanation: 

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cf a.shtml 

Port Roles The role is now a variable assigned to a given port. The root port and designated port roles remain, while the blocking port role is split into the backup and alternate port roles. The Spanning Tree Algorithm (STA) determines the role of a port based on Bridge Protocol Data Units (BPDUs). In order to simplify matters, the thing to remember about a BPDU is there is always a method to compare any two of them and decide whether one is more useful than the other. This is based on the value stored in the BPDU and occasionally on the port on which they are received. This considered, the information in this section explains practical approaches to port roles. 

Compatibility with 802.1D RSTP is able to interoperate with legacy STP protocols. However, it is important to note that the inherent fast convergence benefits of 802.1w are lost when it interacts with legacy bridges. 


Q28. - (Topic 2) 

Which statement is true, as relates to classful or classless routing? 

A. Classful routing protocols send the subnet mask in routing updates. 

B. RIPv1 and OSPF are classless routing protocols. 

C. Automatic summarization at classful boundaries can cause problems on discontiguous subnets. 

D. EIGRP and OSPF are classful routing protocols and summarize routes by default. 

Answer:

Explanation: http://www.ciscopress.com/articles/article.asp?p=174107&seqNum=3 

RIPv1, RIPv2, IGRP, and EIGRP all auto-summarize classful boundaries by default (OSPF does not).To make discontiguous networks work, meaning you don't want classful boundries to summarize, you need to turn off auto-summary. 


Q29. - (Topic 2) 

Which two are advantages of static routing when compared to dynamic routing? (Choose two.) 

A. Configuration complexity decreases as network size increases. 

B. Security increases because only the network administrator may change the routing table. 

C. Route summarization is computed automatically by the router. 

D. Routing tables adapt automatically to topology changes. 

E. An efficient algorithm is used to build routing tables, using automatic updates. 

F. Routing updates are automatically sent to neighbors. 

G. Routing traffic load is reduced when used in stub network links. 

Answer: B,G 

Explanation: 

When reading (or being lectured about) all the glorious details of dynamic routing protocols, it's hard not to come away with the impression that dynamic routing is always better than static routing. It's important to keep in mind that the primary duty of a dynamic routing protocol is to automatically detect and adapt to topological changes in the internetwork. The price of this "automation" is paid in bandwidth, security, and maybe queue space, in memory, and in processing time. A frequent objection to static routing is that it is hard to administer. This criticism may be true of medium to large topologies with many alternative routes, but it is certainly not true of small internetworks with few or no alternative routes. References: http://www.ciscopress.com/articles/article.asp?p=24090&seqNum=6 http://www.ciscopress.com/articles/article.asp?p=24090 


Q30. - (Topic 3) 

What is the advantage of using a multipoint interface instead of point-to-point subinterfaces when configuring a Frame Relay hub in a hub-and-spoke topology? 

A. It avoids split-horizon issues with distance vector routing protocols. 

B. IP addresses can be conserved if VLSM is not being used for subnetting. 

C. A multipoint interface offers greater security compared to point-to-point subinterface configurations. 

D. The multiple IP network addresses required for a multipoint interface provide greater addressing flexibility over point-to-point configurations. 

Answer:

Explanation: 

You do not have to assign a separate subnet per sub-interface .if you're using a Class A network (10.x.x.x/8), you blow the whole network on a few connections (if you used VLSM, you could use a better mask, limit the addresses used). if you used 10.0.0.0/8, you would not be assigning the entire /8 to a single network. You would select a subnet mask for the network and then, you would have to use that mask with all subnets of the network. So if you chose a /24 mask, that would mean that you would have to use a /24 mask for even point-to-point links.