Ccent/ccna Icnd1 100-101 (Cis337)

Explanation: Answer option B is correct.

SW2 would advertise its root cost as the sum of the root cost in the BPDU it received plus the cost of the interface it received it on. A 100-Mbps interface has a default cost of 19, which would make a total of 57 (38 + 19 = 57) as its own root cost, which it would advertise in BPDUs being sent by SW2.

As shown in the explanation, 57 is the correct answer. All the other choices are incorrect.

Objective: Spanning Tree Protocol (IEEE 802.1D)

Answer option C is correct.

The ip address command is syntactically correct, and the mask 255.255.255.128 is a valid mask, so the router will accept the command. The router will add a connected route for the subnet in which 10.101.101.101 255.255.255.128 resides, because the interface is up, and the show ip route command will list the mask in prefix notation. Of the answers, /25 is equal to 255.255.255.128, because 255.255.255.128 represents a total of 25 binary 1s.

The other incorrect masks represent different DDN masks:

/22: 255.255.252.0

/23: 255.255.254.0

/26: 255.255.255.192

Answer options D, E , and C are correct.

Routers focus on Layer 3, and LAN switches focus on Layer 2, when forwarding data. However, both devices must support the lower layers to be able to send and receive the data (Layer 1) and to interpret the data received on each interface by using framing (Layer 2). Routers do not need to examine the UDP or TCP header to forward packets, although the router can do so when implementing some functions, including Access Control Lists (ACL). Switches do not need to think about IP to forward frames. (Note that this question's concepts are covered in many chapters of the ICND1 book; however, Chapter 16 contains an example that shows the underlying concepts.)

d

Answer option D is correct.

If port security is configured on a switch port, and there is a violation of those port security parameters (such as more than the allowed number of source MAC addresses), the default behavior is to place the port into an err-disable state.

All the other answers would not cause this err-disable state. Administratively shut down would show the state of disabled. Incorrect or bad cabling will likely show a state of nonconnect. An access-port assigned to a VLAN that doesn’t exist wouldn’t show a status of err-disable.

Answer options B and C are correct.

Web browsers use HTTP, which in turn uses TCP. The web browser connects to the server with a TCP connection and issues a get request to get the first file in the web page. That object may include instructions to load additional files (objects), again with HTTP get requests. The hostname that identifies the server is located between the double slash (//) and the single slash (/) in the URL; the text after the single slash identifies the web page on that particular server.

a The Cisco 2960 switch comes with all the interfaces ready to go out of the box. There is no need to purchase any power supplies or to activate any products.

a The clock rate command sets the clock rate on the router with the DCE cable, with the units in bits per second. The bandwidth command sets an administrative value that is used for many purposes, but it does not affect the speeds at which the bits are encoded on the link. The csu-speedcommand does not exist on a router.

Answer options B and E are correct.

Because the desirable side will request the trunk, and the auto side will agree, dynamic desirable and dynamic auto will end up in a trunk being formed. Trunk and dynamic auto will end up in a trunk being formed. When configured as a trunk, DTP is still enabled and will request a trunk to the other side, which is configured as auto and will agree to the trunk.

If one side is configured as a trunk and the other is configured as an access port, a trunk will not be negotiated on both sides, and there will be limited connectivity. If both sides are dynamic auto, a trunk will not be negotiated. If both switches are configured as access ports for a specific VLAN, that VLAN will be supported on that link.

Answer option D is correct.

Only nonroot switches have root ports.

The root switch does not have any root ports for the VLAN it is the root of. A root switch has all forwarding ports (as could a nonroot switch if there were no redundant links). A root switch does not have blocking ports, but because it is the root it also does not have any root ports on it. Root switches and nonroot switches both could have designated ports, and the root switch would not have any root ports.

Chapter: Spanning Tree Protocol Concepts

Explanation: Answer option C is correct.

Commands on Cisco routers take effect after Enter is pressed. Remember to save configurations after you have configured your router.

c
The show mac address-table dynamic address 0010.DC56.EC96 command will show what port that MAC address is plugged into on the switch

ab

DA

Segmenting Ethernet networks with a bridge or switch reduces collisions. In addition, each port of a bridge or switch is its own Ethernet segment and does not share bandwidth with the other segments, increasing the bandwidth available across the network.

Answer options E, B , and A are correct.

The RFC 1918 private network numbers are 10.0.0.0, Class Bs between 172.16.0.0 and 172.31.0.0 (inclusive), and all Class C networks that begin with 192.168. All addresses beginning with 127 are reserved, but not as valid private IP addresses.

c) Accounting

Explanation: Answer option B is correct.

When switchport nonegotiate is used, if a connected switch is using dynamic desirable or dynamic auto, it will not form a trunk.

Even with switchport nonegotiate being used, an interface can still be hard coded to become a trunk port. The command is used on a switch, not a router. The command causes DTP message to not be sent. The default is that DTP messages are sent, and the switchport nonegotiate command disables these from being sent.

Explanation: Answer option D is correct.

The FCS field is used for error detection and is included as a trailer in the HDLC frame.

The address field in the HDLC header indicates the Layer 2 destination address. The HDLC header and trailer information doesn’t include the Layer 3 IP destination address (that is in the Layer 3 header information). The Type field in the HDLC header identifies the type of Layer 3 payload that is being encapsulated. A preamble is the concept of a recognizable bit pattern so that the receiving node will realize that a new frame is arriving. In HDLC, this is a field named Flagu

b

a Network layer

The Session layer is responsible for starting, controlling, and ending sessions.

The Transport layer deals with error recovery, segmentation of large application data blocks for transport, and the reassembly of segmented application data.

The OSI Network layer defines the end-to-end routing of data. The similarly-named TCP/IP Network Interface layer, also called the Network Access layer, defines the lowest layer of the TCP/IP model when it is shown as a 4-layer model. (The TCP/IP Link layer, also sometimes called the Network Interface or Network Access layer, may be broken into the Data Link and Physical layers to match the terms used by OSI.)
The Ozone layer is a protective shield designed to protect against various forms of radiation.

Explanation: Answer options B and E are correct.

MAC addresses are 48 bits (6 bytes) long, usually written as 12 hexadecimal digits. In Cisco products, MAC addresses are often displayed 4 hex digits (2 bytes) at a time, separated by periods, for example, 0200.1234.BEEF.

Answer option B is correct.

The FCS field is used for error detection and is included as a trailer in the HDLC frame.

The address field in the HDLC header indicates the Layer 2 destination address. The HDLC header and trailer information doesn’t include the Layer 3 IP destination address (that is in the Layer 3 header information). The Type field in the HDLC header identifies the type of Layer 3 payload that is being encapsulated. A preamble is the concept of a recognizable bit pattern so that the receiving node will realize that a new frame is arriving. In HDLC, this is a field named Flag.

Explanation: Answer option C is correct.

PC1 will use an Ethernet header, the first router will use an HDLC header, and the second router will use an Ethernet header, for a total of three.

HDLC uses HDLC Layer 2 headers for any HDLC next-hop routers in the path. The HDLC would contribute to one of the headers being used in the path between PC1 and PC2.

Explanation: Answer option D is correct.

In the HDLC header, the Type field indicates the type of Layer 3 packet encapsulated within the HDLC Layer 2 frame.

HDLC can encapsulate many different types of protocols, not just IPv4. The FCS field is used for error detection. The Flag field is similar to an Ethernet preamble, which is a specific bit pattern that allows a receiving device to realize that a new frame is arriving. The IP address is in the L3 header, not in the HDLC header.

Answer options A, C , and D are correct.

Leased lines, DSL, and cable are all examples of common Internet access links.

HDLC and PPP are Layer 2 encapsulation methods, not link types.

b

Explanation: Answer option A is correct.

TCP uses a three-way connection establishment flow that must be completed before data transfer can begin. SYN means synchronize the sequence numbers, and ACK means that the acknowledgment field is valid in this header.

Answer options A, C , D , E , and F are correct.

Explanation: Answer option D is correct.

Web browsers connect to web servers by referencing the URL of the web server. The client must find the hostname part of the URL and then find the IP address (not the MAC address) used by that host, typically by using a DNS request. The browser then uses HTTP to get the contents of the web page, with HTTP using TCP. The browser must initiate a TCP connection to the server, which requires a three-way initialization handshake, with two of those messages going from the user's PC to the server.

Explanation: Answer options A and B are correct.

VoIP traffic typically requires low bandwidth but requires low delay and low jitter (variation in delay) and prefers little or no packet loss. Two-way video has the same requirements, but it generates much more traffic. Web applications use HTTP, which uses TCP, which in turn can recover from lost packets.

Answer options A and D are correct.

Web browsers use HTTP, which in turn uses TCP. The web browser connects to the server with a TCP connection and issues a get request to get the first file in the web page. That object may include instructions to load additional files (objects), again with HTTP get requests. The hostname that identifies the server is located between the double slash (//) and the single slash (/) in the URL; the text after the single slash identifies the web page on that particular server.

Explanation: Answer option C is correct.

The switch first creates an entry in its MAC table for the new address; then it forwards the frame appropriately.

Answer option A is correct.

Fragment-free switching checks the first 64 bytes of a frame. It has slightly more latency than cut-through switching.

Answer options A and B are correct.

b

Answer option B is correct.

IOS starts using the commands entered in configuration mode as soon as the user presses Enter at the end of the command. The user does not have to exit configuration mode, issue a command to enable or save the commands, or save the configuration to NVRAM to use the configuration.

Explanation: Answer option A is correct.

The banner motd command displays a banner when you log into the router. The character that follows the motd tells the router that you are done entering the message. Always select a character that you will not use in your message.

Answer option C is correct.

By default, two Cisco 2960 switches that have a crossover cable connected will not automatically form an 802.1Q trunk because of the default trunking setting of dynamic auto. To create a trunk, one of the two switches can be configured to trunk (switchport mode trunk) or to initiate the negotiation of trunking (switchport mode dynamic desirable).

Explanation: Answer options B, C, E , and F are correct.

802.1Q inserts a header after the address and type fields of a normal Ethernet frame.

b

Cisco Discovery Protocol (CDP) can be used to either confirm or fix the documentation shown in a network diagram. Confirming that the network is actually cabled to match the network diagram is a good idea before troubleshooting.

LLDP is similar in function to CDP and is supported by Cisco and other vendors but is not on by default, and therefore is likely not to be available for verifying the topology diagram. PING is a good tool for connectivity testing, but from user mode (without recording options), it doesn’t allow verification of the logical path between devices in the network. Telnet is used for remote connectivity but doesn’t verify the interconnections in the network. 802.1q is a protocol used for trunks and wouldn’t be useful in verifying all the devices in a topology diagram (especially those connections that didn’t involve any type of trunk).

Answer options C and D are correct.

The commands listed in the two correct answers list the same roughly 15 lines of information about a neighbor. The show cdp neighbors command lists only a single line of summary information. The other three answers list commands that list information about the operation of CDP, as opposed to the information learned by CDP.

Explanation: Answer option A is correct.

The show frame signaling command is invalid. LMI is automatically determined, so it will not show in the configuration. The show frame-relay map command shows mapping information, but not LMI information.

Explanation: Answer option B is correct.

You can find a list of devices that have exchanged routing information under Routing Information Sources; only one gateway is listed in the command output. These gateways (remember, the term gateway is just another term for router) are the neighbors known by this router.

Explanation: Answer options D and E are correct.

For 12.150.146.96/27, the number is the subnet number, with a range of valid IP addresses 12.150.146.97 through 12.150.146.126. For 225.16.102.232, the first octet means that the address is a multicast (Class D) address and cannot be assigned to an interface as a unicast IP address. For address 0.102.62.1, the first octet is 0, which is a reserved value. 150.159.216.202/24 is a valid address, with its subnet having a range of valid addresses 150.159.216.1 through 150.159.216.254. 214.122.127.76/26 is also a valid address, in subnet 214.122.127.64, whose range of valid addresses is 214.122.127.65 through 214.122.127.126.
Chapter: Analyzing Existing Subnets
Objective: Practice Analyzing Existing Subnets

Explanation: Answer options B and C are correct.

Since care was taken during the design phase, it is possible to simply add a new subnet to the branch office by adding a secondary IP address to the LAN interface of the router at the branch office. Also, a larger subnet could be assigned, which may or may not be difficult, depending on whether any static IP addresses are configured.

Answer options A and B are correct.

When using the ip route command, you can specify an IP address as the next hop, or an interface out which to send the packet.

Answer option A is correct.

The correct command to apply an ACL to VTY interfaces is access-class under the VTY interfaces.

Answer options B and C are correct.

The term inside refers to a host inside the Enterprise network, which often uses a private (RFC 1918) address inside the Enterprise. The term localrefers to an address used for that host in the local, or Enterprise, network.

Explanation: Answer option A is correct.

You accomplish 1:1 static mapping with the ip nat inside source command, with the first IP address being the inside local address, and the second being the inside global address.

Explanation: Answer option D is correct.

Neighbor Discovery Protocol (NDP) acts as a replacement for several IPv4 protocols, including ARP, as well as providing several new functions for IPv6. ARP does not exist in IPv6.

Answer option A is correct.

The show mac address-table dynamic address 0010.DC56.EC96 command will show what port that MAC address is plugged into on the switch

Explanation: Answer options A, C, and E are correct.

By blocking on specific ports that would otherwise be parallel Layer 2 paths, STP prevents Layer 2 loops, thus preventing broadcast storms, preventing MAC table instability due to the a single-source Layer 2 address showing up on multiple different ports, and preventing multiple copies of a single frame from being forwarded (because spanning tree is blocking on enough ports to stop the forwarding of frames on parallel paths).

STP does not use any TTL mechanism in a frame header (there is not one there); that is why it must do blocking on Layer 2 ports where an otherwise parallel path would be. STP performs blocking on Layer 2 ports, not Layer 3 ports.

Answer option C is correct.

The device with the lowest root cost becomes the designated port for a segment, and the other switch then moves to blocking state for that link.

The lowest cost to root is the leading factor in determining who will be designated and who will block. If the costs were equal, the lowest BID between the two nonroot switches would be used to determine who would be designated for that link.

Answer options A, C, and E are correct.

Without spanning tree, and if parallel Layer 2 paths exist, there would be loops. As a result, broadcast storms, duplicate frames, and MAC table flapping (where the switch is relearning the same MAC address but on different ports back and forth over and over again) would all be symptoms.

There are no TTL mechanisms at Layer 2. IP addresses are a Layer 3 function and would not be caused from a Layer 2 loop.

Answer options A and C are correct.

STP would not be needed if there were no redundant parallel Layer 2 paths in the network. One way of removing parallel paths is to make them into a single logical link, as with EtherChannel.

If there were only two switches, and they had parallel paths, STP would be needed to prevent the Layer 2 loop. Rapid Spanning Tree is still spanning tree, and that alone would not remove the need for it. Parallel paths can be created over access or trunk ports, and that alone would not remove the need for spanning tree.

Answer options A, B, C, and D are correct.

Speed, duplex, allowed VLANS on trunk ports, and the same access VLAN on access ports should all match for interfaces belonging to the EtherChannel bundle.

The MAC addresses for the ports do not have to match, but all the other listed parameters must match.

Explanation: Answer option E is correct.

Ping uses the Internet Control Message Protocol (ICMP).

Ping uses ICMP, not TCP, UDP, ARP, or HTTP.

Answer option D is correct.

Autosummarization has been a feature of IP routing protocols for a long time, since the original classful routing protocols. As such, it was a feature of routing protocols that existed on older, less powerful routers, that had less memory, so by today's standards, it uses little memory, and little processing. However, like those early classful routing protocols, autosummarization assumes that networks are contiguous.

Answer option C is correct.

The STP cost between the switch that is advertising the STP BPDU and the root of STP is the sender’s root cost.

Bridge IDs are just identifiers of devices in STP and by themselves do not represent cost. The hello timer is used in spanning tree and is controlled by the root switch, as is the forward delay timer.

Answer option A is correct.

BPDU Guard will shutdown a port that receives a BPDU packet from another switch. Remember that BPDU Guard is a Cisco Proprietary protocol.

Answer option D is correct.

The bandwidth command affects the default metric calculation for both OSPF and EIGRP. It also affects the utilization statistics on serial interfaces. It has other uses as well. The clock rate interface subcommand can affect the link's speed when building a back-to-back serial link.

Answer option E is correct.

None of the provided orders are correct.

The correct order is as follows:

D: Elect a root bridge.
B: Elect a root port for each nonroot bridge.
A: Elect a designated port for each segment.
C: Root ports and designated ports transition to the forwarding state.

Answer options B, C, D, and E are correct.

Legacy STP is 802.1D. PVST+ is the Cisco implementation of that protocol. 802.1w is Rapid Spanning Tree, and Rapid PVST+ is Cisco’s implementation of that protocol.

802.1Q is a trunking protocol.

Explanation: Answer option A is correct.

The switchport port-security mac-address 0010.DC56.EC96 command will limit only the MAC address listed on the port. This port will be shutdown if a different MAC address appears on the port.

Answer option E is correct.

BPDU Guard shuts down a port if a BPDU is seen on that port and does not allow forwarding of further traffic until that port is enabled again.

You can configure BPDU Guard on ports that are enabled with PortFast. PortFast is usually used on access ports, not ports facing other switches. PortFast does not shut down ports based on seeing a BPDU (which is what BPDU Guard does). BPDU Guard shuts down the port for all traffic.

Answer options B, C, and D are correct.

Root ports (on nonroot switches) are in a forwarding state, as are designated ports. All the ports on the root switch are designated ports, and as a result are all forwarding.

Root switches do not have any root ports; they are all designated ports. Blocking ports are not in a forwarding state.

Explanation: Answer options D and E are correct.

Active and passive are the two mode choices for LACP.

Auto and desirable are two modes for PAgP, and the on option indicates that neither LACP nor PAgP messages will be sent.

Explanation: Answer options B and E are correct.

Trunks carry traffic for multiple VLANs only if those VLANs exist on the switch and are allowed on the trunked interfaces. EtherChannel allows the bonding of multiple interfaces together for one larger logical interface.

A VLAN is a Layer 2 broadcast domain, although normally a single IP (Layer 3) subnet is associated with each Layer 2 VLAN. DTP is dangerous because it could allow an attacker to dynamically negotiate a trunk with a switch, and as therefore it is recommended that it be turned off. A VLAN mismatch is not automatically adjusted by DTP and should be the same on both ends of a trunk.

Explanation: Answer options A, B, and D are correct.

Most high-speed Internet connections from the home include a router and either a cable or DSL modem, often contained in a single device. Most connections use Network Address Translation and a LAN switch to allow multiple devices to connect to the home network. Most home office Internet connections do not use a router with a serial interface; these interfaces typically connect Enterprise routers to serial links or Frame Relay access links.

fd

ag

b

b

a

d

c

a

ce

TCP/IP application layer protocols provide services to the application software running on a computer. The application layer does not define the application itself, but it defines services that applications need.

HTTP did not exist until Tim Berners-Lee created the first web browser and web server in the early 1990s

TCP/IP transport layer includes a smaller number of protocols. The two most commonly used transport layer protocols are the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP).

Transport layer protocols provide services to the application layer protocols that reside one layer higher in the TCP/IP model

Application

Transport

Network

Data Link

Physical

the two computers use a protocol (an agreed-to set of rules) to communicate with the same layer on another computer. The protocol defined by each layer uses a header that is transmitted between the computers to communicate what each computer wants to do. Header information added by a layer of the sending computer is processed by the same layer of the receiving computer

On a single computer, one layer provides a service to a higher layer. The software or hardware that implements the higher later requests that the next lower layer perform the needed function.

Active Virtual Gateway (AVG)

GLBP elects one AVG (Active Virtual Gateway) for each group.

Neighbor Discovery Protocol (NDP)

acts as a replacement for several IPv4 protocols, including ARP, as well as providing several new functions for IPv6. ARP does not exist in IPv6.

The application layer includes many protocols. The transport layer includes fewer, most notably, TCP and UDP. The TCP/IP network layer includes a small number of protocols, but only one major protocol: the Internet Protocol (IP). In fact, the name TCP/IP is simply the names of the two most common protocols (TCP and IP) separated by a /.

IP provides several features, most importantly, addressing and routing. This section begins by comparing IP’s addressing and routing with another commonly known system that uses addressing and routing: the postal service.

The TCP/IP model’s original link layer defines the protocols and hardware required to deliver data across some physical network. The term link refers to the physical connections, or links, between two devices and the protocols used to control those links.

Host or router then uses link-layer details to send that packet to the next host/router.

segment for the transport layer,

packet for the network layer,

and frame for the data link layer

OSI

7.Application

6.Presentation

5.Session

4.Transport

3.Network

2.Data Link

1.Physical

TCP/IP

5-7.Application

4.Transport

3.Internet

1-2 Link (Data Link & Physical)

b

a

c

Layer 3 of the OSI model deals primarily with IP addressing and routing.

cbe

Routers, wireless access point Ethernet ports, and PC NICs all send using pins 1 and 2, whereas hubs and LAN switches transmit on pins 3 and 6. Straight-through cables connect devices that use opposite pin pairs for sending, because the cable does not need to cross the pairs.

c

B

b

d

Answer options D and A are correct.

The network layer defines logical addressing, in contrast to physical addressing. The logical address structure allows easy grouping of addresses, which makes routing more efficient. Path selection refers to the process of choosing the best routes to use in the network. Physical addressing and arbitration typically are data link layer functions, and error recovery typically is a transport layer function.

Explanation: Answer option B is correct.

PC1 will send an Ethernet frame to Router1, with PC1’s MAC address as the source address and Router1’s MAC address as the destination address. Router1 will remove the encapsulated IP packet from that Ethernet frame, discarding the frame header and trailer. Router1 will forward the IP packet by first encapsulating it inside an HDLC frame, but Router1 will not encapsulate the Ethernet frame in the HDLC frame, but rather the IP packet. Router2 will deencapsulate the IP packet from the HDLC frame and forward it onto the Ethernet LAN, adding a new Ethernet header and trailer, but this header will differ. It will list Router2’s MAC address as the source address and PC2’s MAC address as the destination address.

Answer options A and E are correct.

Without any subnetting in use, all addresses in the same network as 10.1.1.1—all addresses in Class A network 10.0.0.0—must be on the same LAN. Addresses separated from that network by some router cannot be in network 10.0.0.0. So, the two correct answers are the only two answers that list a valid unicast IP address that is not in network 10.0.0.0.

b

Explanation: Answer options B, C, D, and A are correct.

These are the steps to routing logic.

Answer option A is correct.

POP3 uses TCP.

Answer option B is correct.
The URL is composed of the protocol, host name, and name of the web page

Explanation: Answer options D and A are correct.
SYN means "Synchronize the sequence numbers," which is one necessary component in initialization for TCP. FIN is short for "Finished."

BC

SSH requires the use of usernames in addition to a password. Using the username global command would be one way to define usernames (and matching passwords) to support SSH. The vty lines would also need to be configured to require the use of usernames, with the login local vty subcommand being one such option. The transport input ssh command could be part of a meaningful configuration, but it is not a global configuration command (as claimed in one wrong answer). Likewise, one answer refers to theusername command as a command in vty config mode, which is also the wrong mode.

ADF

To allow access through Telnet, the switch must have password security enabled, at a minimum using the password vty line configuration subcommand. Additionally, the switch needs an IP address (configured under one VLAN interface) and a default gateway when the switch needs to communicate with hosts in a different subnet.

Answer option F is correct.

Cisco switches do not have a command to disable autonegotiation of speed and duplex. Instead, a switch port that has both speed andduplex configured disables autonegotiation.

10BASE-T and 100BASE-T use two pair of wires in a UTP cable. A straight-through cable works correctly when the nodes use opposite pairs for transmitting.

1 to 1

2 to 2

3 to 3

6 to 6

The crossover cable pinout crosses the pair at the transmit pins on each device to the receive pins on the opposite device.

1 to 3

2 to 6

3 to 1

6 to 2

Crossover cable: If the endpoints transmit on the same pin pair
Straight-through cable: If the endpoints transmit on different pin pairs

1,2

3,6

cable crosses

1 to 3

2 to 6

but it also crosses

4 to 7

5 to 8

Preamble - 7 (synchronization)

SFD - 1 (signifies that the next byte begins the destination MAC address field)

Destination - 6

Source - 6

Type - 2 - (defines the type of protocol listed inside the frame)

Data and Pad - 46/1500 - (holds L3PDU)

FCS - 4 - (provide a method for the receiving NIC to determine whether the frame experienced transmission error)

HDLC - Ethernet equivalent

Flag - Preamble

Address - Destination Address

Type - Type

FCS - FCS

100 Meters

d)

a

Cut-through switching

One of three options for internal processing on some models of Cisco LAN switches in which the frame is forwarded as soon as enough of the Ethernet header has been received for the switch to make a forwarding decision, including forwarding the first bits of the frame before the whole frame is received.

Fragment-free switching

One of three internal processing options on some Cisco LAN switches in which the first bits of the frame can be forwarded before the entire frame is received, but not until the first 64 bytes of the frame are received, in which case, in a well-designed LAN, collision fragments should not occur as a result of this forwarding logic.

Store-and-forward switching

One of three internal processing options on some Cisco LAN switches in which the Ethernet frame must be completely received before the switch can begin forwarding the first bit of the frame.

ABD

c

c

B
A switch floods broadcast frames, multicast frames (if no multicast optimizations are enabled), and unknown unicast destination frames (frames whose destination MAC address is not in the MAC address table).

D
Switches need to learn the location of each MAC address used in the LAN relative to that local switch. When a switch sends a frame, the source MAC identifies the sender. The interface in which the frame arrives identifies the local switch interface closest to that node in the LAN topology.

B
A switch compares the destination address to the MAC address table. If a matching entry is found, the switch knows out which interface to forward the frame. If no matching entry is found, the switch floods the frame.

CD
When the frame sent by PC3 arrives at the switch, the switch has learned a MAC address table entry for only 1111.1111.1111, PC1’s MAC address. PC3’s frame, addressed to 2222.2222.2222, is flooded, which means it is forwarded out all interfaces except for the interface on which the frame arrived.

E

A switch floods broadcast frames, multicast frames (if no multicast optimizations are enabled), and unknown unicast destination frames (frames whose destination MAC address is not in the MAC address table).

Answer options C and A are correct.

The IEEE Ethernet standards support 100-meter links when using UTP cabling. Most standards that use fiber-optic cabling, like the standards in the two correct answers, use lengths longer than 100 meters.

switch can be configure to sue one of three actions when a violation occurs. All 3 cause the switch to discard the offending frame

Protect - discard traffic, no SNMP log, no disabling of interface

Restrict - discard traffic, restrict, sends SNMP log message, no disabling of interface

Shutdown - discard traffic, restrict, sends SNMP log message, disables of interface

switchport mode access

switchport access vlan

switchport trunk native vlan

the interface range FastEthernet
0/11 - 20 command tells IOS that the next subcommand(s) apply to interfaces Fa0/11 through Fa0/20

Emma# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Emma(config)# interface FastEthernet 0/1
Emma(config-if)# duplex full
Emma(config-if)# speed 100
Emma(config-if)# description Server1 connects here
Emma(config-if)# exit
Emma(config)# interface range FastEthernet 0/11 - 20
Emma(config-if-range)# description end-users connect_here

Step 1. Make the switch interface either a static access or trunk interface, using the switchport
mode access or the switchport mode trunk interface subcommands, respectively.
Step 2. Enable port security using the switchport port-security interface subcommand.
Step 3. (Optional) Override the default maximum number of allowed MAC addresses associated with the interface (1) by using the switchport port-security maximum number interface subcommand.
Step 4. (Optional) Override the default action to take upon a security violation (shutdown) using the switchport port-security violation {protect | restrict | shutdown} interface subcommand.
Step 5. (Optional) Predefine any allowed source MAC address(es) for this interface, using the switchport port-security mac-address mac-address command. Use the command multiple times to define more than one MAC address.

Step 6. (Optional) Tell the switch to “sticky learn” dynamically learned MAC addresses with the switchport port-security mac-address sticky interface subcommand.

(Lines omitted for brevity)
interface FastEthernet0/1
switchport mode access
switchport port-security
switchport port-security mac-address 0200.1111.1111
! interface FastEthernet0/2
switchport mode access
switchport port-security
switchport port-security mac-address sticky
! interface FastEthernet0/3
switchport mode access
switchport port-security
! interface FastEthernet0/4
switchport mode access
switchport port-security
switchport port-security maximum 8

Explanation: Run the following set of commands to configure the OSPF protocol on each router:

R1

R1>enable
R1#configure terminal
R1(config)#router ospf 2
R1(config-router)#network 192.168.36.12 0.0.0.3 area 0
R1(config-router)#network 192.168.60.96 0.0.0.7 area 0

R2

R2>enable
R2#configure terminal
R2(config)#router ospf 2
R2(config-router)#network 192.168.36.12 0.0.0.3 area 0
R2(config-router)#network 192.168.60.64 0.0.0.7 area 0

10Base-T - 802.3

100Base-T - 802.3u

1000Base-LX - 802.3an

1000Base-T - 802.3z

10GBase-T - 802.3ab

switchport access vlan 10

switchport mode access

switchport port-security

switchport port-security violation restrict

switchport port-security mac-address 0090.ABCD.EF10

FastEthernet0/1 is administratively down, line protocol is down (disabled)
Hardware is Fast Ethernet, address is 0019.e86a.1181 (bia 0019.e86a.1181)
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, Loopback not set
Keepalive set (10 sec)
Auto-duplex, Auto-speed, media type is 10/100BaseTX
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 01:04:27, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
64660 packets input, 6290547 bytes
Received 56426 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog
0 input packets with dribble condition detected

no ip domain-lookup

The output lists [1/0], where 1 is the administrative distance and 0 is the metric.

ip access-list extended BlockUDP

ab

Answer option C is correct.

On a new switch, creating and assigning existing ports to a new VLAN, results in a single new broadcast domain (VLAN) on that switch.Each VLAN is a separate broadcast domain, so when we add one VLAN, we get one new Layer 2 broadcast domain. The 12 ports already existed on the switch as 12 collision domains before the new VLAN and assignment of any ports to the VLAN.

Explanation: Answer option B is correct.

If the router fails the POST, it will stop the boot process until the cause of failure has been repaired.

Explanation: Answer option B is correct.

The error state can only be resolved by manually shutting the interface down and then bringing it back up again.

Explanation: Answer option C is correct.

By default, a Cisco switch has all its interfaces in the same broadcast domain, known as VLAN 1.

Explanation: Answer option A is correct.

The login banner is designed to be the permanent banner, as opposed to the MOTD (Message of the Day).

FALSE

Switch ports are by default in the autonegotiate state.

TRUE

It provides low-level encryption.

router>enable

router>config terminal

router(config)#interface

router(config-if)#switchport port-security

switch# configure terminal

switch(config)# interface vethernet 1

switch(config-if)# switchport trunk allowed vlan 5-15

switch(config-if)#

If you have the service password-encryption command enabled, the password you enter is encrypted. When you display it with the more system:running-config command, it is displayed in encrypted form.

If you specify an encryption type, you must provide an encrypted password—an encrypted password you copy from another router configuration

The service password-encryption command does not provide a high level of network security

Router(config)# privilege modelevel level command-string

Router(config)# enable secret level level {0 |5} password-string

Router(config)# exit

-------------------------

Configures the specified privilege level to allow access to the specified command

Sets the password for the specified privilege level. This is the password users will enter after entering the enable level command to access the specified level.

•0 indicates an unencrypted password string follows; 5 indicates an encrypted password

string follows.

Exists global configuration mode and returns to EXEC mode.

(Optional) Saves the configuration to the startup configuration file in NVRAM.

Note The do keyword allows execution of EXEC commands in configuration mode.

router>enable

router#configure terminal

router(config)#interface interface

router(config-if)#switchport port-security

1. Enter privileged mode

2. Enter global configuration mode

3. Enter interface configuration mode

4. Enable the switchport security feature

router(config-if)#switchport port-security maximum value

router(config-if)#switchport port-security violation {protect | restrict | shutdown}

router#configure terminal

router(config)#interface interface

router(config-if)#switchport port-security mac-address mac-address

router#configure terminal

router(config)#interface interface

router(config-if)#switchport port-security mac-address sticky

router#configure terminal

router(config)#interface f0/1

router(config-if)#switchport port-security

router(config-if)#switchport port-security mac-address 0000.1111.2222

router(config)#interface f0/2

router(config-if)#switchport port-security

router(config-if)#switchport port-security mac-address sticky

channel-group 1 mode on

spanning-tree vlan 2 cost 1

configure terminal

interface fa0/11

spanning-tree portfas

ip ospf cost 14

Many switches can attach to the same Ethernet segment, but in modern networks, normally two switches connect to each link. The switch with the lowest root cost, as compared with the other switches attached to the same link, is placed in forwarding state. That switch is the designated switch, and that switch’s interface, attached to that segment, is called the designated port (DP).

32768

4

a

4

3

4

4

2

4

2

2

1,4

1,2

1000Base-LX

Single-mode 5km

1000Base-ZX

70 km lengh

Ethernet over MPLS

Multiprotocol Label Switching

DSL Access Multiplexer

this layer provides an interface between the communications software and any application that needs to communicate outside the computer on which the application resides. It also define process for user authentication.

define and negotiate data formats.

Encryption is defined here

defines how to start, control, and end conversations.

Includes control and management of multiple bidirectional messages so that the application can be notified if only some of a series of messages are completed

Multiplexing using ports

Error recovery

Flow control using windowing

Connection establishment and termination

Ordered data transfer and data segmentation

logical addressing

routing

path determination

Defines the rules that determine when a device can send data over a particular medium. Data link protocols also define the format of a header and trailer that allows devices attached to the medium to successfully send and receive data.

Defines standards from otehr organization

1) Starts with a snapshot of the two companies (starts with a snapshot of the publisher)

2) Than continues with triggers to track changes (changes are tracked with triggers)

3) sudden surprise at the subscriber are pushed to view during the merger (Changes at the subscriber are synced to the publisher)

4) yes multi merge is allowed

(Multiple subscribers are allowed)

5) when conflicts occur they must be resolved (conflicts may occur and when they do you need the ability to detect and resolve them)

1) single

(only a single DB snapshot can exist for source DB)

2) total access to all catalogs of people (full text catalogs on the source DB must be dropped and then re-created after the revert completes)

3) yesterday's log is useless

(Because the transaction log is rebuild transaction log chain is broken)

4) unaccessible are all swinger clubs

(Both the source DB and the DB snapshot are offline during the revert)

5) file stream

(The source DB cannot be set up with Filestream)

The switch starts sending the frame out the output port as soon as possible

waits to receive the first 64 bytes of a frame and then sends is forward

4

1)

1

2

1

3

4

1

2

3

6

4,5

The show cdp neighbors cmd lists one line of output per neighbor. However, it does list the platform information of the neighbor, which typically includes the hardware model number.

show cdp entry hannah commands lists a group of messages about the neighboring router, including more detail about the hardware model and the IOS version

show cdp neighbor

this cmd lists one line of output per neighbor. However, it does list the platform information of the neighbor, which typically includes the hardware model number

show cdp entry hannah

this cmd lists a group of messages about the neighboring router, including more detail about the hardware model and the IOS version

1,3

show mac address-table cmd

Lists all entries in the siwtch's MAC address table, including dynamically learned and statically defined addresses.

1,2

1, 6

1

if both line and protocol are up and you still cannot ping, it is probably an IP address issues.

3

Show vlan brief / show vlan

lists each VLAN and all interfaces assigned to that VLAN.

2

Protocol status down is most likely a Layer 2 issue

1,2,4

CDP reveals the interface on the remore router or switch on the other end of the link that sent the CDP advertisement

1

3,4

show interface switchport cmd

lists both the administrative and operational status of each port, When a switch considers a port to be trunking, the cmd lists an operational trunking state of "trunk"

show interface switchport cmd

lists both the administrative and operational status of each port, When a switch considers a port to be trunking, the cmd lists an operational trunking state of "trunk"

show interfaces trunk cmd

This cmd lists a set of interfaces: the interfaces that are currently operating as trunks

1

Each access port of a switch can only be a member of one VLAN. VLAN membership can therefore be reassigned by simply issuing the switchport mode access vlan vlan-id command on the port.

1

if a VLAN with member ports is deleted, those ports are isolated and connected devices cannot communicate until the ports are assigned to an existing VLAN.

1

Routers use VLAN trunking instead of a separate link for each VLAN through the port connected to the switch.

1,3,4

Cisco LAN switches can be configured to server (default), client, or transparent VTP mode. They can also be set to off mode.

4

1)

Both NAT and PAT can support multiple protocols for each of their translations. PAT translates multiple inside local addresses into a single global address. PAT is also used with pools when there are more inside devices than addresses in the pool and the keyword overload has been used in the configuration.

NAT is a one-to-one translation of IP to IP

5

The show ip cache flow cmd displays a summary of NetFlow statistics, including which protocols are in use

1,4

Digital signatures can be used for authenticating the VPN peer on the other side of the tunnel, and 3DES is an encryption algorithm that can be used for encryption.MD5 and SHA-1 are a hashing algorithm used for data integrity. AES is an encryption algorithm used for privacy of data.

1,5

show license cmd provides info on the current licenses active on the device

show version cmd does provide some of the details about licensing near the end of the output

type-B usb console

the older is RJ-45

Class A determine via binary

00000000 = 0

01111111 = 127

Class B determine via binary

10 000000 = 128

11 000000 = 192

Class C determine via binary

110 00000 = 192

111 00000 = 223

1) shutdown vlan vlan-id (global config)

2) shutdown (vlan config)

switchport trunk allowed vlan { add | all | except | remove } vlan-list

this cmd provides a way to easily add and remove VLANs from the list

Inter-Switch Link (ISL) (proprietary)

IEEE 802.1Q

two

the normal range and the extended range

All switches can use normal-range VLANs with values from 1 to 1005.

Only some siwtches can use extended -range VLANs 1005 to 4094

1. From config mode, use the vlan vlan-id global config cmd to create the VLAN and to move the user into VLAN config mode

2. (Optional) use the name name VLAN subcmd to list a name for the VLAN

3. For desirable interfaces enter interface config mode

4. Use the switchport access vlan id-number interface subcmd to specify the VLAN number associated with that interface

5. (Optional) disable trunking on that same interface, so that the interface does not negotiate to become a trunk, use the switchport mode access interface subcmd

VTP VLAN Trunking Protocl

Cisco-proprietary protocol and tool used to advertise each VLAN configure in one switch so that all the other switches in the network

vtp mode transparent global cmd

or

vtp mode off

to check the VTP status use

vtp mode off

server

client

transparent

(standard construct template)

switchport trunk encapsulation {dot1q | isl | negotiate }

s#configure terminal

s(config)# enable secret cisco

s(config)# hostname ema

ema(config)#line console 0

ema(config-line)#password faith

ema(config-line)# login

ema(config-line)# exit

ema(config)#line vty 0 15

ema(config-line)# password love

ema(config-line)# login

ema(config-line)# end

ema#

transport input { all | none | telnet | ssh }

the console and vty lines with the password cmd

username password

service password-encryption

global config cmd

it affects has password cmd in both console and vty modes and username password global cmd

lists the interface status of the VLAN 1

lists the interface IP address

Device identifier - typically the hostname

Address list - network and data-link address

Port identifier - the interface on the remote router or switch

auxiliary port is similar to console port. The main difference with an auxiliary port is that it also allows you to config modem cmd so that modem can be connected to the router

s#config t

s(config)# ip access-list standard Tod

s(config-std-nacl)#

s(config)# ip routing

s(config)# router rip

s(config-router)#

user exec mode - limited to basic monitoring cmd

privileged exec mode - provides access to all other router cmd

global configuration mode - cmd that affect the entire system

specific config mode - cmd that affect interface/process only

setup mode - interactive config mode

t#config t

t(config)#line aux 0

t(config-line)#login

t(config-line)#password aux

t(config-line)#login

t#config t

t(config)#service password-encryption

t(config)#exit

t#run

sh run | ?

sh run | begin interface

show controllers int

router#sh controllers s0/0/0

Interface Serial0/0/0

Hardware is GT96K

DTE V.35idb at 0x4342FCB0, driver data structure 0x434373D4

router#sh controllers s0/2/0

Interface Serial0/2/0

Hardware is GT96K

DCE V.35, clock rate 10000000

router(config)#hostname todd

todd(config)#ip domain-name lamle.com

todd(config)#username todd password lamle

todd(config)#crypto key generate rsa

todd(config)#ip ssh version 2

todd(config)#line vty 0 15

todd(config)#transport input ssh telnet

access interface is a LAN network design term that refers to a switch interface connected to end-user devices, configured so that it does not use VLAN trunking

trunk interface

A switch interface configured so that it operate using VLAN trunking

Trunking administrative mode

The configured trunking setting on a Cisco switch interface, as configured with the switchport mode command

Trunking operational mode

The current behavior of a Cisco switch interface for VLAN trunking

One of three VTP operational modes. Switches in transparent mode can configure VLANs, but they do no tell other switches about the changes, and they do not learn about VLAN changes from other switches

access - always act as an access port

trunk - always act as trunk port

dynamic desirable - initiates negotiation messages and responds to negotiation messages to dynamically choose whether to start using trunking

dynamic auto - passively waits to receive trunk negotiation messages, at which point the switch will respond and negotiate whether to use trunking

asks the switch to both negotiate as well as to beign the negotiation process, rather than waiting on the other device

this cmd lists information about all interfaces that currently operationally tunk

show ip ospf

show ipv6 ospf

show ip protocol

show ipv6 protocol

show ip ospf interface

show ipv6 ospf interface

show ip ospf interface brief

show ipv6 ospf interface brief

show ip ospf neighbors

show ipv6 ospf neighbors

show ip ospf database

show ipv6 ospf database

show ip route ospf

show ipv6 route ospf

Quite sending OSPF hellos on the interface

Ignore received Hellos on the interface

Do not form neighbor relationships over the interfaces

continue to advertise about any subnet connect to the interface

passive-interface gigabitethernet0/0

CEF Cisco Express Forwarding

A method of internal processing on Cisco routers, meant to make the routing process very efficient, doing so by caching IP routes in a table that can be searched very quickly, and by remembering data link headers rather than building them for every packet that is forwarded.

Connected route

On a router, an IP route added to the routing table when the router interfaces is both up and has an IP address configured. The route is for the subnet that can be calculated based on the configured IP address and mask.

Static route

An IP route on a router created by the user configuring the details of the route on the local router.

ABR Are Border Router

A router using OSPF in which the router has interfaces in multiple OSPF areas

Convergence

The time required to react to changes in the network, removing and adding new, better routes so that the current best routes are in all the routers' routing table

Distance vector

The logic behind the behavior of some interior routing protocols, such as RIP. Distance vector routing algorithms call for each router to send its entire routing table in each update but only to its neighbors. distance vector routing algorithms can be prone to routing loops but are computationally simple than line-state routing algorithms.

A classification of the underlying algorithm used in some routing protocols. Link-state protocols build a detailed database that lists link (subnet) and their state (up, down), from which the best routes can then be calculated.

In OSPF, the name of the data structure that resides inside the LSDB and describes in detail the various components in a network, including routers and links

LSDB

Link-state database

In OSPF, the data structure in RAM of router that holds the various LSAs, wth the collective LSAs representing the entire topology of the network

SPF - Shortest path first

The name of the algorithm used by link-state routing protocol to analyze the LSDB and find the least-cost router to each subnet.

a list of IOS global configuration commands that can match only a packet's source IP address, for the purpose of deciding which packets to discard and which to allow through the router

A list of IOS access-list global configuration commands that can match multiple parts of an IP packet, including the source and destination IP address and TCP/UDP ports, for the purpose of deciding which packets to discard and which to allow through the router

an ACL that identifies the various statements in the ACL based on a name, rather that a number

for packets sen to and from a host that resides inside the trusted part of a network that uses NAT, a term referring to the IP address used in the headers of those when those packets traverse the global internet

for packets sent to and from a host that resides inside the trusted part of a network that uses NAT, a term referring to the IP address used in the headers of those packets traverse the enterprise (private) part of the network

port address translation

a NAT feature in which one inside global IP address support over 60K concurrent TCP and UDP connection

NAT - Network Address Translation

A mechanism for reducing the need for globally unique IP addresses. NAT allows an organization with addresses that are not globally unique to connect to the Internet, by translating those addresses into public addresses in the globally routable address space.

An IPv6 prefix that defines an IPv6 address block made up of global unicast address, assigned to one organization, so that the organization has a block of globally uniques IPv6 addresses to use in its network

A type of unicast IPv6 address that has been allocated from a range of public globally uniques IP addresses, as registered through IANA/ICANN, its member agencies, and other registries or IPSs

A type of IPv6 unicast address meant as a replacement for IPv4 private addresses

A specific IPv6 multicast address, FF02::1, with link-local scope, used to send packets to all devices on the link that support IPv6

All-routers multicast address

A specific IPv6 multicast address, FF02::2, with link-local scope, used to send packets to all devices that act as IPv6 routers on the local link

Literally, a standard for an extended unique identifier that is 64 bits long. Specifically for IPv6, a set of rules for forming a 64-bit identifier, used as the interface ID in IPv6 addresses, by starting with a 48-bit MAC address, inserting FFE (hex) in the middle, and inverting the seventh bit

A type of unicast IPv6 address that represents an interface on a single data link. Packets sent to a link-local address cross only that particular link and are never forwarded to other subnets by a router. Used for communication that do not need to leave the local link/

With IPv6 multicasts, a term that refers to the parts of the network to which a multicast packet can flow, with link-local referring to the fact that the packet stays on the subnet in which it originated

A term used in IPv6 to refer to how hosts first check whether another host is using a unicast address before the first host uses that address

A message defined by the IPv6 Neighbor Discovery Protocol (NDP), used to declare to other neighbors a host's MAC address. Sometimes sent in response to a previously received NDP Neighbor Solicitation (NS) messages.

NS

A message defined by the IPv6 NDP, used to ask a neighbor to reply with a Neighbor Advertisement which lists the neighbor's MAC address.

RA

A message defined by the IPv6 NDP, used by routers to announce their willingness to act as an IPv6 router on a link. These can be sent in response to a previously received NDP Router Solicitation (RS) message

A message defined by the IPv6 Neighbor Discover Protocol, used to ask any routers on the link to reply, identifying the router, plus other configuration settings

A term used in IPv6 to contrast with stateless DHCP. Stateful DHCP keeps track of which clients have been assigned which IPv6 addresses

SLAAC - Stateless Address Auto-configuration

a feature of IPV6 in which a host or router can be assigned an IPv6 unicast address without the need for a stateful DHCP server

A term used in IPv6 to contrast with stateful DHCP. Stateless DHCP servers don't lease IPv6 addresses to clients. Instead, they supply other useful information, such as DNS server IP address, but with no need to track information about the clients.

A and C

An unsubnetted Class A, B, or C network has two parts: the network and host parts.

ab

The number of network, subnet, and host bits must total 32 bits

Explanation: Answer options D and A are correct.

Cisco routers have an on/off switch, but Cisco switches generally do not.

Answer options A and C are correct.

To route packets, a router interface must have an IP address assigned and be in an “up and up” interface state. For a serial link created in a lab, without using CSU/DSUs, one router must be configured with a clock rate command to the speed of the link. The bandwidth and description commands are not required to make a link operational.

Answer options C and A are correct.

The show ip interface brief command lists all the interface IPv4 addresses but none of the masks. The show version command lists none of the IP addresses and none of the masks. The other three commands list both the address and mask.

Explanation: Answer option D is correct.

With the no ip subnet-zero command configured, the router will not allow any interfaces to be configured with an IP address in the zero subnet. Of the listed answers, subnet 10.0.0.0 255.254.0.0 is a zero subnet, with a range of addresses from 10.0.0.1 to 10.1.255.254. The ip address 10.1.2.2 255.254.0.0 command would be rejected.

Explanation: Answer options B and D are correct.

The route defines the group of addresses represented by the route using the subnet ID and mask. The router can use those numbers to find the range of addresses that should be matched by this route. The other two answers list facts useful when forwarding packets that happen to match the route.

Lesson: Configuring IPv4 Addresses and Routes

Explanation: Answer options E and F are correct.

Of all the commands listed, only the two correct answers are syntactically correct router configuration commands. The command to enable 802.1Q trunking is encapsulation dot1q vlan_id.

Explanation: Answer option C is correct.

The correct syntax lists a subnet number, then a subnet mask in dotted-decimal form, and then either an outgoing interface or a next-hop IP address.

Explanation: Answer option C is correct.

PCs use two-option logic: send local packets (destined for hosts in the same subnet) directly, and send remote packets (destined for hosts in other subnets) to the default gateway/router. In this case, the PC’s own IP address is 192.168.5.77, with mask 255.255.224.0, so it is in subnet 192.168.4.64/27. This subnet has a range of addresses from 192.168.4.64 to 192.168.4.95, including the subnet and broadcast address. As a result, the PC sends the packet to its default gateway. As for the other incorrect answers, if the ping command had used a host name, it would have first asked a DNS server to resolve the name. Also, the PC already has an IP address, so DHCP would not be needed.

Lesson: Configuring IPv4 Addresses and Routes

Explanation: Answer option B is correct.

The configuration of the Layer 3 switch’s routing feature uses VLAN interfaces, with the interface number matching the VLAN ID. The matching connected routes, like all connected IP routes, will list the interfaces but not a next-hop IP address. The three connected routes will list the VLAN interfaces 1, 2, and 3, respectively.

Explanation: Answer option C is correct.

The network 10.0.0.0 0.255.255.255 area 0 command works, because it matches all interfaces whose first octet is 10. The rest of the commands match as follows: all addresses that end with 0.0.0 (wildcard mask 255.0.0.0); all addresses that begin with 10.0.0 (wildcard mask 0.0.0.255); and all addresses that begin 10.0 (wildcard mask 0.0.255.255).

Explanation: Answer options E and D are correct.

Of the three wrong answers, two are real commands that simply do not happen to list the OSPF neighbors. show ip ospf interface brief lists interfaces on which OSPF is enabled, but does not list neighbors. show ip interface lists IPv4 details about interfaces, but none related to OSPF. One incorrect answer, show ip neighbor, is not a valid IOS command.

Explanation: Answer option C is correct.

Link-state protocols do not exchange data that lists routes. They do list metric information, but it is per-interface information, and it is not tied to a subnet. Link-state protocols do require the SPF algorithm to take the varied pieces of information and create routes based on that information.

Explanation: Answer options B and C are correct.

Both versions of RIP use the same hop-count metric.

Explanation: Answer option A is correct.

The network 0.0.0.0 255.255.255.255 area 0 command matches all IP addresses as a result of the 255.255.255.255 wildcard mask, so this command enables OSPF in Area 0 on all interfaces. The answer with wildcard mask 0.255.255.0 is illegal, because it represents more than one string of binary 0s separated by binary 1s. The answer with x’s is syntactically incorrect. The answer with wildcard mask 255.0.0.0 means “Match all addresses whose last three octets are 0.0.0,” so none of the three interfaces are matched.

in link-state protocols, also called SPF protocols, the routers each create three separate tables.

One for tracking directly attached neighbors

One to determine the topology of the entire internetwork

One used as the routing table

Stored in the microcode of the ROM

The bootstrap is used to bring a router up during initialization. It boots the router and then loads the IOS

Stored in the ROM,

The POST is used to check the basic functionality of the router hardware and determines which interfaces are present

ROM - Called RXBOOR or boot loader by Cisco,

a small IOS in ROM that can be used to bring up an interface and load a Cisco IOS into flash memory. The mini-IOS can also perform a few other maintenance operations.

Used to hold packet buffers, ARP cache, routing tables, and also the software and data structures that allow the router to function. Running-config is stored in RAM, and most routers expand the IOS from flash into RAM upon boot.

Packet buffer - RAM

Routing table - RAM

Stored in ROM

The ROM monitor is used for manufacturing, testing, and trouble-shooting, as well as running a mini-IOS when the IOS in flash fails to load.

Used to start and maintain the router. Holds the POST and the bootstrap program as well as the mini-IOS

Stores the Cisco OPS by default. Flash memory is not erased when the router is reloaded. It is EEPROM created by Intel.

Used to hold the router and switch configuration. NVRAM is not erased when the router or switch is reloaded. Does not store an IPS. The configuration register is stored in NVRAM.

Used to control how the router boots up.

This value can be found as the last line of the show version command output and by default is set to 0x2012, which tells the router to load the IOS from flash memory as well as to load the configuration from NVRAM.

#config t

(config)#ip domain-lookup

(config)#ip name-server 4.4.4.4

(config)#ip domain-name lamle.com

cdp holdime

length of time that receiver must keep the packets it receives from neighboring devices

cdp time - rate at which CDP packets are sent on all active interfaces

show ip dhcp server statistics

show ip dhcp server statistics

(config)#logging host 172.16.10.1

(config)#service timestamps log datetime msec

#config ter

(config)#interface fa0/0

(config-if)#ip helper-address 10.10.10.254

show ip address bindings

If you need to provide address from a DHCP server to hosts that aren't on the same LAN as the DHCP server, you can configure your router interface to relay or forward the DHCP client request

Router#show cdp

Global CDP information:

Sending CDP packets every 60 seconds

Sending a holdtime value of 180 seconds

Sending CDPv2 advertisements is enabled

The following is sample output from the show cdp entry command with no limits. Information about the neighbor device.cisco.com is displayed, including device ID, address and protocol, platform, interface, hold time, and version.

outer# show cdp entry device.cisco.com-------------------------Device ID: device.cisco.comEntry address(es): IP address: 192.168.68.18 CLNS address: 490001.1111.1111.1111.00 DECnet address: 10.1Platform: cisco 4500, Capabilities: RouterInterface: Ethernet0/1, Port ID (outgoing port): Ethernet0Holdtime : 125 secVersion :Cisco IOS SoftwareCisco IOS (tm) 4500 Software (C4500-J-M), Version 12.1(2)Copyright (c) 1986-2000 by cisco Systems, Inc.

Compiled Mon 07-Apr-00 19:51 by joeuser

show cdp entry protocol command. Only information about the protocols enabled on device.cisco.com is displayed.

Router# show cdp entry device.cisco.com protocol

Protocol information for device.cisco.com:

IP address: 192.168.68.18

CLNS address: 490001.1111.1111.1111.00

DECnet address: 10.1

how cdp interface

Serial0 is up, line protocol is up, encapsulation is SMDS

Sending CDP packets every 60 seconds

Holdtime is 180 seconds

Ethernet0 is up, line protocol is up, encapsulation is ARPA

Sending CDP packets every 60 seconds

Holdtime is 180 seconds

The following is sample output from the show cdp entry protocol command. Only information about the protocols enabled on device.cisco.com is displayed.

Router# show cdp entry device.cisco.com protocol

Protocol information for device.cisco.com:

IP address: 192.168.68.18

CLNS address: 490001.1111.1111.1111.00

DECnet address: 10.1

Router# show cdp entry device.cisco.com

-------------------------

Device ID: device.cisco.com

Entry address(es):

IP address: 192.168.68.18

CLNS address: 490001.1111.1111.1111.00

DECnet address: 10.1

Platform: cisco 4500, Capabilities: Router

Interface: Ethernet0/1, Port ID (outgoing port): Ethernet0

Holdtime : 125 sec

Version :

Cisco IOS Software

Cisco IOS (tm) 4500 Software (C4500-J-M), Version 12.1(2)

Copyright (c) 1986-2000 by cisco Systems, Inc.

Compiled Mon 07-Apr-00 19:51 by joeuser

Router#show cdp

Global CDP information:

Sending CDP packets every 60 seconds

Sending a holdtime value of 180 seconds

Sending CDPv2 advertisements is enabled