Chapter 1
After completion of this chapter, you should be able to:





Describe the use of a hierarchical network for a small business.
Describe recommendations for designing a network that is scalable.
Describe the type of switches available for small-to-medium-sized business networks.
Describe the type of routers available for small-to-medium-sized business networks.
Configure and verify basic settings on a Cisco IOS device.
1.1 Implementing a Network Design
1. What do all enterprise networks have to support?
a. Support critical applications
b. Support converged network traffic
c. Support diverse business needs
d. Provide centralized administrative control
2. What is the expected up time for enterprise networks?
99.999%
3. List and explain the three layers of the hierarchical design model.
a. Access layer –
The access layer provides connectivity for the users.
b. Distribution layer –
The distribution layer is used to forward traffic from one local network to another.
c. Core layer –
The core layer represents a high-speed backbone layer between dispersed networks.
4. Explain how a two-tier hierarchical design differs from the three tier hierarchical model.
In a two-tier hierarchical design, the core and distribution layers are collapsed into one layer,
reducing cost and complexity.
5. The Cisco Enterprise Architecture divides the network into functional components while still
maintaining the core, distribution, and access layers. What are the primary Cisco Enterprise
Architecture modules?
1
a. Enterprise Campus
b. Enterprise Edge
c. Service Provider Edge
d. Remote
6. What is the purpose of the Enterprise Edge?
It consists of the Internet, VPN, and WAN modules connecting the enterprise with the service
provider's network.
7. What is the function of the Service Provider Edge?
The Service Provider Edge provides Internet, Public Switched Telephone Network (PSTN), and
WAN services.
8. Explain what a failure domain is.
A failure domain is the area of a network that is impacted when a critical device or network
service experiences problems.
9. Explain the advantage of using a building, or departmental, switch block.
Each switch block acts independently of the others. As a result, the failure of a single device
does not cause the network to go down. Even the failure of an entire switch block does not
affect a significant number of end users.
10. Explain what a network designer must develop to enable a network to be available and to scale
effectively and easily.
a. Use expandable, modular equipment or clustered devices that can be easily upgraded to
increase capabilities. Device modules can be added to the existing equipment to support new
features and devices without requiring major equipment upgrades. Some devices can be
integrated in a cluster to act as one device to simplify management and configuration.
b. Design a hierarchical network to include modules that can be added, upgraded, and
modified, as necessary, without affecting the design of the other functional areas of the
2
network. For example, creating a separate access layer that can be expanded without affecting
the distribution and core layers of the campus network.
c. Create an IPv4 or IPv6 address strategy that is hierarchical. Careful IPv4 address planning
eliminates the need to re-address the network to support additional users and services.
d. Choose routers or multilayer switches to limit broadcasts and filter other undesirable traffic
from the network. Use Layer 3 devices to filter and reduce traffic to the network core.
11. Explain what more advanced network design requirements might include?
a. Implementing redundant links in the network between critical devices and between access
layer and core layer devices.
b. Implementing multiple links between equipment, with either link aggregation (EtherChannel)
or equal cost load balancing, to increase bandwidth. Combining multiple Ethernet links into a
single, load-balanced EtherChannel configuration increases available bandwidth. EtherChannel
implementations can be used when budget restrictions prohibit purchasing high-speed
interfaces and fiber runs.
c. Implementing wireless connectivity to allow for mobility and expansion.
d. Using a scalable routing protocol and implementing features within that routing protocol to
isolate routing updates and minimize the size of the routing table.
12. Why is Spanning Tree Protocol (STP) required in a switched Ethernet network?
Redundant paths in a switched Ethernet network may cause logical Layer 2 loops.
13. Explain how does STP work?
By providing a mechanism for disabling redundant paths in a switched network until the path is
necessary, such as when failures occur.
14. Explain what EtherChannel is and how it works.
Link aggregation allows an administrator to increase the amount of bandwidth between devices
by creating one logical link made up of several physical links.
15. What considerations need to be taken into account when implementing a wireless network?
a. the types of wireless devices to use
b. wireless coverage requirements
c. interference considerations
d. security considerations
3
16. What is a popular link-state protocol that works well with Enterprise networks using a hierarchical
design?
Open Shortest Path First (OSPF)
17. Which distance vector protocol works well with larger networks?
Enhanced Interior Gateway Routing Protocol (EIGRP)
18. Draw a line connecting the correct term to its correct description.
Link Aggregation
Protocol with distance-vector behaviors.
OSPF
Alternate data pathway.
EIGRP
Protocol which uses a backbone area.
Redundancy
Multiple Ethernet interface links combined into a single
bandwidth channel.
1.2 Selecting Network Devices
19. There are five categories of switches for enterprise networks, these are:
a. Campus LAN Switches
b. Cloud-Managed Switches
c. Data Center Switches
d. Service Provider Switches
e. Virtual Networking
20. Explain the following terms:
a. Cost –
The cost of a switch will depend on the number and speed of the interfaces, supported
features, and expansion capability.
b. Port Density –
Network switches must support the appropriate number of devices on the network.
c. Power –
4
It is now common to power access points, IP phones, and even compact switches using Power
over Ethernet (PoE). In addition to PoE considerations, some chassis-based switches support
redundant power supplies.
d. Reliability –
The switch should provide continuous access to the network.
E. Port Speed –
The speed of the network connection is of primary concern to end users.
f. Frame Buffers –
The ability of the switch to store frames is important in a network where there may be
congested ports to servers or other areas of the network.
g. Scalability –
The number of users on a network typically grows over time; therefore, the switch should
provide the opportunity for growth.
21. Define forwarding rates.
Define the processing capabilities of a switch by rating how much data the switch can process
per second.
22. What is wire speed?
It is the data rate that each Ethernet port on the switch is capable of attaining.
23. What does PoE allow?
PoE allows the switch to deliver power to a device over the existing Ethernet cabling.
24. Explain how PoE pass-through works.
It allows a network administrator to power PoE devices connected to the switch, as well as the
switch itself, by drawing power from certain upstream switches.
25. Where are multilayer switches typically deployed in an organization's switched network?
The core and distribution layers
26. What are multilayer switches typically characterized by?
a. Their ability to build a routing table
b. Their support a few routing protocols
c. Their ability to forward IP packets at a rate close to that of Layer 2 forwarding
26. Label each switch criteria.
5
27. In the distribution layer of an enterprise network, routing is required. Without the routing process,
packets cannot leave the local network.
28. What beneficial functions do Routers serve?
a. Provide broadcast containment
b. Connect remote locations
c. Group users logically by application or department
d. Provide enhanced security
29. List and explain the three categories of routers.
a. Branch Routers –
Branch routers optimize branch services on a single platform while delivering an optimal
application experience across branch and WAN infrastructures. Highly available branch
6
networks must ensure fast recovery from typical faults, while minimizing or eliminating the
impact on service, and provide simple network configuration and management.
b. Network Edge Routers –
Network edge routers enable the network edge to deliver high-performance, highly secure, and
reliable services that unite campus, data center, and branch networks. Network edge routers
must deliver enhance quality of service and nonstop video and mobile capabilities.
c. Service Provider Routers –
Service provider routers differentiate the service portfolio and increase revenues by delivering
end-to-end scalable solutions and subscriber-aware services. These systems are designed to
simplify and enhance the operation and deployment of service-delivery networks.
30. What does an IOS refer to?
IOS refers to the package of routing, switching, security, and other internetworking
technologies integrated into a single multitasking operating system.
31. Explain the following terms in detail.
a. Out-of-band management –
Is used for initial configuration or when a network connection is unavailable. Configuration
using out-of-band management requires:
Direct connection to console or AUX port
Terminal emulation client
b. In-band management –
Is used to monitor and make configuration changes to a network device over a network
connection. Configuration using in-band management requires:
At least one network interface on the device to be connected and operational
Telnet, SSH, or HTTP to access a Cisco device
32. Which command can be used to verify and save the routing configuration?
copy running-config startup-config
33. Explain the following list of commonly used IOC commands.
a. show ip protocols –
Displays information about the routing protocols configured. If OSPF is configured, this includes
the OSPF process ID, the router ID, networks the router is advertising, the neighbors the router
is receiving updates from, and the default administrative distance, which is 110 for OSPF.
7
b. show ip route - Displays routing table information, including: routing codes, known networks,
administrative distance and metrics, how routes were learned, next hop, static routes, and
default routes.
c. show ip ospf neighbor –
Displays information about OSPF neighbors that have been learned, including the Router ID of
the neighbor, priority, the state (Full = adjacency has been formed), the IP address, and the
local interface that learned of the neighbor.
d. show interfaces –
Displays interfaces with line (protocol) status, bandwidth, delay, reliability, encapsulation,
duplex, and I/O statistics. If specified without a specific interface designation, all interfaces will
be displayed. If a specific interface is specified after the command, information about that
interface only will be displayed.
e. show ip interfaces –
Displays interface information, including: protocol status, the IP address, if a helper address is
configured, and whether an ACL is enabled on the interface. If specified without a specific
interface designation, all interfaces will be displayed. If a specific interface is specified after the
command, information about that interface only will be displayed.
f. show ip interface brief –
Displays all interfaces with IP addressing information and interface and line protocols status.
g. show protocols - Displays information about the routed protocol that is enabled, and the
protocol status of interfaces.
34. What is the purpose of the delete flash:vlan.dat command on a switch?
To erase any VLAN information.
35. Explain the following list of switch IOS commands.
a. show port-security –
Displays any ports with security activated. To examine a specific interface, include the interface
ID. Information included in the output: the maximum addresses allowed, current count,
security violation count, and action to be taken.
b. show port-security address –
Displays all secure MAC addresses configured on all switch interfaces.
c. show interfaces –
Displays one or all interfaces with line (protocol) status, bandwidth, delay, reliability,
encapsulation, duplex, and I/O statistics.
8
d. show mac-address-table –
Displays all MAC addresses that the switch has learned, how those addresses were learned
(dynamic/static), the port number, and the VLAN assigned to the port.
9