Net+ 3.2 Lesson

Layer 1

all interfaces receive unicast and broadcasts

security issues with sniffing unicast

Hub

Layer 1

although not used anymore, understanding how they operate is foundational

Hub

every port runs at half-duplex

speeds are 10/100 and SHARED between devices

Hub

wiring is special with hubs with the Tx connecting to the host and Rx connection to the hub

Hub

there are no configuration options for hubs

Hub

Multiple Choice

Hubs operate at what layer?

• Physical layer (Layer 1)
• Transport layer (Layer 4)
• Network layer (Layer 3)
• Data link layer (Layer 2)

Multiple Choice

Hubs send these two types of transmissions to every port.

• Unicast and Broadcast
• Unicast and Multicast
• Broadcast and Anycast
• Multicast and Anycast

Multiple Choice

Hubs operate at what type of duplex?

• Full-duplex
• Simplex
• Bidirectional
• Half-duplex

Multiple Choice

With hubs, they have to be wired specifically; which end of the wire connects to the host?

• Tx

• Rx

• Fx

Multiple Choice

What settings can be configured on a hub?

• none

• host name

• switch ports

• duplex mode

Physically connected devices that share network resources

Physical Segment

Although they might not be "physically" connected, the network devices are still sharing resources

Logical Segment

Multiple Choice

What device would you use to connect 2 physical networks to make one logical network?

• Hub
• Modem
• Switch
• Bridge

Layer 2 Device

Learns MAC addresses and builds a forward table

Reduces collisions by reducing nodes on one physical network

Bridges

Multiple Choice

Bridges operate on what layer?

• Transport layer
• Network layer
• Data Link layer
• Application layer

Multiple Choice

Bridges build a forwarding table based on what information?

• MAC addresses of devices connected to their ports.
• Network protocols used by connected devices.
• Device names of connected devices.
• IP addresses of devices connected to their ports.

Multiple Choice

If a bridge has devices in the MAC Address table that have not been connected with in a while, what will happen?

• The bridge will notify the user about inactive MAC addresses.
• The bridge will age out the inactive MAC addresses from its table.
• The bridge will increase the timeout for inactive MAC addresses.
• The bridge will permanently store all MAC addresses regardless of activity.

Multiple Choice

Using a bridge reduces collisions on the network because

• Using a bridge merges all collision domains into one.
• Bridges eliminate the need for switches in a network.
• Using a bridge reduces collisions by creating separate collision domains.
• Bridges increase the number of devices on the network.

Multiple Choice

Bridges are widely used today

• True

• Not True

CD -> physically connected devices that can be separated by bridges; now separated by switch ports

BD -> established by layer 3 devices (routers) but they technically run at layer 2

Collision Domains v.
Broadcast

Multiple Choice

Today, collision domains are kept separate by what?

• switch ports

• bridge ports

• router ports

Multiple Choice

Broadcast Domains are established on what layer?

• Transport layer (Layer 4)
• Network layer (Layer 3)
• Data Link layer (Layer 2)
• Application layer (Layer 7)

Apartment Idea

Apartment Building: Think of a large apartment building with multiple floors. Each floor represents a network segment. A bridge acts like a mail carrier who sorts incoming mail (data packets) based on the apartment number (destination MAC address) and delivers them to the correct floor (network segment).

Traffic Control

Imagine a busy intersection with multiple lanes of traffic. A bridge is like a traffic controller, separating incoming traffic onto specific lanes (network segments) based on their destination. It prevents unnecessary traffic (data packets) from flooding the entire network.

Layer 2 Device
Establishes CD and BD boundaries
Ports restrict collision domains
All ports on same broadcast domain unless VLANs established

Switches

Data Link Layer
intelligent directors on a network
learn MAC addresses and efficiently direct data packets to correct device
improves network performance and reduces collisions

Switches

Layer 2
When a switch port established a link between 2 nodes, it is known as MICROSEGMENTATION

MICRO - SEGMANT

Switches

On a SWITCH, a collision will occur in half-duplex, but it will not affect the whole network because it is isolated to one port. Usually the speeds are 10/100

Switches

Multiple Choice

A network switch operates at what layer?

• Application layer (Layer 7)
• Transport layer (Layer 4)
• Data Link layer (Layer 2)
• Network layer (Layer 3)

Multiple Choice

A single port on a switch reduces what type of domain?

• Collision domain
• VLAN domain
• Network domain
• Broadcast domain

Multiple Choice

All switch ports will be on the same broadcast domain unless WHAT is configured?

• Switch ports are configured to use static IPs.
• All devices are connected to a single router.
• VLANs are configured.
• Switch ports are set to full duplex.

Multiple Choice

What is it called when a switch port established a point to point link between 2 nodes?

• Microsegmentation

• Broadcast link
• Multicast link
• Full-duplex link

Multiple Choice

A collision will occur on a network switch when a port operates at what speed

• Half-duplex mode at 1 Mbps
• Full-duplex mode at 1 Gbps
• Half-duplex mode at 10 Mbps or 100 Mbps
• Full-duplex mode at 10 Mbps

Analogy

Think of a waitress in a restaurant who takes orders (data packets) from tables (devices) and delivers them directly to the intended kitchen station (destination device) based on the table number (MAC address)

can be added without configuration
usually less expensive

Unmanaged Switch

usually found on bigger networks
settings can be configured
if not configured, will act as an unmanaged switch

Managed Switch

switches that can be connected together and operate as a group
it will act as a "single unit"

Stackable Switch

modular switch has slots for plug-in cards, so it can be customized

fixed switch CANNOT be customized

Modular/Fixed

can be installed into a standard size rack

smaller switches -> 5 to 8 ports will be desktop

Desktop/Rack-Mounted

Multiple Choice

You need to connect a printer that needs to be on the network in an office that only has 2 open network ports; both ports are being used by the phone and the PC. What type of switch would you use to expand the network in the office?

• managed desktop switch

• unmanaged desktop switch

• managed rack mounted switch

• unmanaged rack mounted switch

Multiple Choice

Your network is expanding into the basement of your building; the network service installer hanged a cabinet in the closet; more than 15 devices will be tied into the network; what type of network switch would you need?

• managed desktop switch

• unmanaged desktop switch

• managed rack mounted switch

• unmanaged rack mounted switch

Multiple Choice

You run an enterprise network where 96 devices are active on the 1st floor; you want to consolidate your management of those devices; what type of switch could you invest in to achieve this goal?

• stackable managed switch

• stackable unmanaged switch

• modular managed switch

• modular unmanaged switch

Performed at CLI
called Cisco ISO
User Exec Mode = >
Priv EXEC Mode = #
Global Config Mode = (config#)

Switch Interface Configuration

User Exec Mode = >
read-only mode
runs basic troubleshooting tools

Switch Interface Configuration

Priv EXEC Mode = #
allows user to
report config
show system status
reboot/shutdown
backup/restore system
activated using the enable command

Switch Interface Configuration

Global Config Mode = (config#)
allows user to:
write config updates
activated by command configure terminal from PRIV mode

Switch Interface Configuration

Interfaces identified by type/slot/port

GigabitEthernet 0/2 (G0/2)

port #2 on first 10/100/1000 slot

most switches have only one slot, unless modular/stackable

CLI port naming

​

switches support a range of ethernet standards

most of the time, ports are set to auto-negotiate the speed

static configs can be setup also

auto-negotiation

shutdown -> disables port
no shutdown -> enables port
speed & duplex commands
usually set to auto
switchport -> configures port settings
such as access or no access

CLI INT commands

Multiple Choice

Which command disables an interface on Cisco IOS?

• enable
• no shutdown
• shutdown
• reset

Multiple Choice

Which command can adjust the speed of an interface on Cisco IOS?

• interface speed
• set speed
• change speed
• speed

Multiple Choice

Which command can configure switching characteristics on Cisco IOS?

• vlan
• router
• interface
• switchport

Multiple Choice

Which command brings you to User EXEC mode on Cisco IOS?

• logout
• show version
• configure terminal
• enable

exit -> returns to previous mode
copy running-config startup-config
writes the changes to memory

CLI commands

Multiple Choice

Which CLI mode is read only on the CIsco IOS?

• User EXEC mode
• Interface Configuration mode
• Global Configuration mode
• Privileged EXEC mode

Multiple Choice

Which CLI mode allows users to show system status on Cisco IOS?

• User mode
• Configuration mode
• Privileged mode
• Enable mode

Multiple Choice

Which CLI mode allows users to backup and restore the system on Cisco IOS?

• User mode
• Configuration mode
• Privileged exec mode

• Disable mode

Multiple Choice

Global configuration mode is shown as what in Cisco IOS?

• Router(config)# or Switch(config)#
• Router#
• Switch(configure)#
• Router(configure)#

Multiple Choice

FastEthernet0/8 is where on the network device?

• 100mbps on the 8th port of the device

• 1000mbps on the 8th port of the device

• 10mbps on the 8th port of the device

Multiple Choice

G0/24 is where on the network device?

• 100mbps on the 24th port of the device

• 1000mbps on the 24th port of the device

• 10mbps on the 24th port of the device

Multiple Choice

When a switch communicates with an end host and agrees on a speed, that is called?

• Speed negotiation
• Link agreement
• Data exchange
• Autonegotiation

Multiple Choice

Which commands returns you to User Exec mode after making a change on Cisco IOS?

• logout
• end
• quit
• exit

Multiple Select

Which command helps you save the configuration to memory in Cisco IOS?

• save config
• copy running-config startup-config
• backup configuration
• write memory

Word Cloud

Write one command you remember from Cisco IOS.

Poll

Rate this lesson

• Global Config

• User EXEV

• User

• I crashed out