DOC

CCNA 3 and 4 Companion Guide, 3rd Edition (CNAP)

By Eugene Williams,2014-06-17 08:09
10 views 0
CCNA 3 and 4 Companion Guide, 3rd Edition (CNAP) ...

    rdCCNA 3 and 4 Companion Guide, 3 Edition

    ISBN: 1-58713-113-7

    Cisco Press

    Errata

CCNA 3 (Chapters 2 through 10)

Chapter 2

    Introduction to Classless Routing

    Page 66 In Figure 2-12, the commands in the figure should be applied in two portions:

    First enter “router rip” and that will put the router into router configuration

    mode. Then, on the second line, enter the “version 2” command.

Page 66 In Example 2-4, highlight:

    Sending updates every 30 seconds, next due in 12 seconds

    Invalid after 180 seconds, hold down 180, flushed after 240

Page 67 In the second paragraph, delete the second sentence, ―In Example 2-4, 18 seconds

    have passed since Router A received an update from Router B.‖

    Page 71 In Figure 2-13, Default Routing w/RIP, the following destination IP address

    should replace the destination IP address between Hong Kong 1 and the Internet

    cloud in the graphic:

    192.168.20.2

    Page 72 In Example 2-9, Default Route, change the IP address to:

    HongKong1 (config )#ip route 0.0.0.0 0.0.0.0 192.168.20.2

    Page 72 In the third paragraph, the third sentence should read, ―In the diagram, Hong

    Kong 1 has only one way out to the Internet through the interface 192.168.20.2.‖

Chapter 3 (p. 77)

    Single-Area OSPF

    Page 79 In the second paragraph, the second and third sentences should read, ―Every

    router in the OSPF area, as in Figure 3-4, has the same link-state database.

    Therefore, every router has the same information about the state of the links and

    every other router’s neighbors.‖

Page 80 In the first paragraph, the first sentence should read, “Each router keeps a list of

    adjacent neighbors, called the adjacency database. The adjacency database is a

    list of all the neighbor routers to which a router has established bidirectional

    communication. This is unique to each router.”

    Page 83 Figure 3-7 should be replaced with the following figure:

Page 85 In the sixth paragraph, the first sentence should read, ―OSPF uses the shortest-

    path first algorithm to determine the best path to a destination.‖

Page 85 In the sixth paragraph, the third sentence should read, ―Edsger Wybe Dijkstra, a

    Dutch computer scientist, formulated the shortest path-algorithm, also

    known as Dijkstra’s algorithm.

Page 86 In the first paragraph, the first four sentences should read, ―A router will try to

    become adjacent, or neighbor, to at least one other router on each IP

    network to which it is connected. OSPF routers determine which routers to

    become adjacent to based on the type of network they are connected to. Some

    routers may try to become adjacent to all neighbor routers. Other routers may

    try to become adjacent to only one or two neighbor routers.

Page 87 In the first paragraph, delete the fifth sentence, ―Using the preceding example

    numbers, only 5 and 10 sets of link states need be sent, respectively.‖

Page 90 The next to the last paragraph should refer to Figure 3-13.

Page 93 The third paragraph should read, ―In Figure 3-15, after the DR acknowledges

    receipt of the LSU, it floods the LSU to all OSPF routers on the network

    using the multicast address 224.0.0.5. Each router acknowledges receipt of

    the LSU with an LSAck.

    Page 97 The first paragraph should read, ―OSPF uses cost as the metric for determining

    the best route. A cost is associated with the output side of each router

    interface. Costs are also associated with extremely derived routing data. In

    general, the path cost is calculated using the formula 10^8/bandwidth, where

    bandwidth is expressed in bps. The system administrator can also configure

    cost by other methods. The lower the cost, the more likely the interface is to

    be used to forward data traffic. The Cisco IOS automatically determines cost

    based on the bandwidth of the interface.

Page 98 In Table 3-4, the title at the top of the first column should read, ―Link Type and

    Bandwidth.‖

Page 99 Add spaces in the second command so it reads:

    router (config-router) # area area-number authentication

Chapter 4 (p. 115)

    Enhanced Interior Gateway Routing Protocol

     Page 121 In the first paragraph, the first bullet should read:

    ; Feasible distance (FD) The feasible distance (FD) is the lowest

    calculated metric to each destination. For example, the feasible distance to

    32.0.0.0 is 2195456 as indicated in Example 4-2.

     Page 122 At the top of the page, the second bullet should read:

    Route statusRoutes are identified as being either passive, which means that the

    route is stable and ready for use, or active, which means that the route is in the

    process of being recomputed by DUAL.

Chapter 5 (p. 147)

    Switching Concepts and LAN Design

    Page 148 In the third paragraph, the fifth sentence should read, ―A hub does not make

    decisions when receiving data signals; it simply regenerates the data signals that

    it receives to all devices connected, except for the device that originally sent

    the signal.”

Page 151 In the second paragraph, the second sentence should read, “Routers do not

    forward broadcasts unless they are programmed to do so.”

    Page 153 In the ―Elements of Ethernet/802.3 Networks‖ section, in the first paragraph, the

    first and second sentences should be replaced with, “Ethernet is a broadcast

    transmission technology. Therefore network devices such as computers,

    printers, and file servers communicate with one another over a shared

    network medium. The performance of a shared medium Ethernet/802.3 LAN

    can be negatively affected by several factors.”

    Page 153 In Figure 5-6, the text under the last bar in the graph should read, ―Desktop Video

    Conferencing.

    Page 159 In Figure 5-12, Segments 1 and 2 should look like Segments 3 and 4. Segments

    1 and 2 should show the three hosts connecting to three ports on the hub, like

    in Segments 3 and 4.

Page 163 The first sentence should read, ―Switching is a technology that decreases

    congestion in Ethernet, Token Ring, and Fiber Distributed Data Interface (FDDI)

    LANs by reducing traffic on each segment, which increases bandwidth for

    each host.”

    Page 163 In the second paragraph, the two bulleted statements should read:

    ; Switching data framesThe process of receiving a frame on a switch interface,

    selecting the correct forwarding switch port(s), and forwarding the frame.

    ; Maintaining switching operationsSwitches build and maintain forwarding

    tables. Switches also construct and maintain a loop-free topology across the

    LAN.