Q25
What data structure is described in the graphic?A. FDDI frameB. Token Ring frameC. Ethernet frameD. IP datagramE. TCP segmentF. UDP datagramAns: E
Reference:
CCNA Self-Study CCNA INTRO exam certification Guide (Cisco Press, ISBN 1-58720-094-5) page 151


Q26
You are the network administrator at CertKing . CertKing has been assigned the IP address 189.66.1.0 by
its Internet Service Provider. Your newly appointed CertKing trainee wants to know how many hosts will
be supported on each subnet if you divide the network by using the 255.255.255.224 subnet mask.
What would your reply be?A. 14B. 16C. 30D. 32E. 62F. 64Ans: C
The subnet mask 255.255.255.224 is a 27 bit mask (11111111.11111111.11111111.11100000). It uses 3 bits
from the host Id for the network ID, leaving 5 bits for host addresses. We can calculate the number of hosts
supported by this subnet by using the 2n-2 formula where n represents the number of host bits. In this case it
will be 5. 25-2 gives us 30.
Incorrect Anss:
A: Subnet mask 255.255.255.240 will give us 14 host addresses.
B: Subnet mask 255.255.255.240 will give us a total of 16 addresses. However, we must still subtract two
addresses (the network address and the broadcast address) to determine the maximum number of hosts the
subnet will support.
D: Subnet mask 255.255.255.224 will give us a total of 32 addresses. However, we must still subtract two
addresses (the network address and the broadcast address) to determine the maximum number of hosts the
subnet will support.
E: Subnet mask 255.255.255.192 will give us 62 host addresses.
F: Subnet mask 255.255.255.192 will give us a total of 64 addresses. However, we must still subtract two
addresses (the network address and the broadcast address) to determine the maximum number of hosts the
subnet will support.
Reference:
CertKing 640-821 Study Guide, Section 2, "IP Addressing and Subnetting"


Q27
You are a technician at CertKing . Your newly appointed CertKing trainee wants to know what the
purpose of flow control is the CertKing network.
What would your reply be?A. It ensures that data is retransmitted if an acknowledgment is not received.B. It reassembles segments in the correct order on the destination device.C. It provides a mechanism for the receiver to control the transmission speed.D. It regulates the size of each datagram segment.Ans: D
Reference:
CCNA Self-Study CCNA INTRO exam certification Guide (Cisco Press, ISBN 1-58720-094-5) page 161


Q28
You are a technician at CertKing . Your newly appointed CertKing trainee wants to know what the CDP
is.
What would your reply be? (Choose all that apply.)A. It is globally enabled by default on Cisco routers.B. It is globally enabled by default on all routers.C. It is a proprietary protocol.D. It is a non-proprietary protocol.E. It can be used to gather hardware and protocol information about neighbor devices.Ans: A, C, E

Explanation:
Cisco Discovery Protocol (CDP) is a Cisco proprietary protocol designed to help administrators collect
information about local and remote devices. You can use the CDP to gather hardware and protocol information
about neighbor devices, which can be useful for troubleshooting and documenting the network.
The CDP discovers basic information about neighboring routers and switches, without needing to know the
passwords for the neighboring devices. CDP supports any LAN, HDLC, Frame Relay, and ATM interface- in
fact, it supports any interface that supports the use of SNAP headers. The router or switch can discover Layer 2
and layer 3 addressing details of neighboring router without even configuring that Layer 3 protocol - this is
because CDP is not dependant on any particular Layer 3 protocol.
Reference:
CertKing 640-821 Study Guide, Section 3.4 "Using the Cisco Discovery Protocol"


Q29
You are a technician at CertKing . Your newly appointed CertKing trainee wants to know what sequence
of events occurs when a router is powered up.
What would your reply be?A. POST, locate configuration statements, apply configuration statements, locate Cisco IOS software, load
Cisco IOS software.B. Locate Cisco IOS software, load Cisco IOS software, locate configuration statements, apply
configuration statements, POST.C. Test software routines, POST, load configuration files, load Cisco IOS software, test Cisco IOS
software.D. POST, locate Cisco IOS software, load the Cisco IOS software, locate configuration statements, apply
configuration statements.E. Load and test IOS, load configuration files, test software routines, POST.Ans: D

Explanation:
1. The router performs a power-on self-test (POST) to discover and verify the hardware.
2. The router loads and runs bootstrap code from ROM.
3. The router finds the IOS or other software and loads it.
4. The router finds the configuration file and loads it into running config.
Reference:
CCNA Self-Study CCNA INTRO exam certification Guide (Cisco Press, ISBN 1-58720-094-5) page 197


Q30
You are a trainee technician at CertKing . You are instructed to enlarge the area covered by a single LAN
segment on the CertKing network.
Which Layer 1 devices can you use? (Choose all that apply.)A. A switch.B. A router.C. A network adapter card.D. A hub.E. A repeater.Ans: D E

Explanation:
o A hub simply repeats the electrical signal and makes no attempt to interpret the electrical signal (layer 1)
as a LAN frame (Layer 2). So, a hub actually performs OSI layer 1 functions, repeating an electrical
signal, whereas a switch performs OSI layer 2 functions, actually interpreting Ethernet header
information, particularly addresses, to make forwarding decisions.
o Because the repeater does not interpret what the bits mean, but does examine and generate electrical
signals, a repeater is considered to operate at Layer 1.
Reference:
CCNA Self-Study CCNA INTRO exam certification Guide (Cisco Press, ISBN 1-58720-094-5) page 55+62