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What is the primary purpose of a VLAN? - correct answer ✅To create a broadcast domain; enable segmentation or isolation of broadcast traffic.
Unassigned Cisco switch ports remain in which VLAN? - correct answer
✅VLAN 1
Do VLANs prevent broadcast storms? - correct answer ✅No, they minimize the size and effect of the broadcast storm on neighbor switches and hosts.
What are four advantages to using VLANs? - correct answer ✅1. Enable access to network services based on logical requirements.
- Network security is optimized with VLANs that enable managing and filtering sensitive traffic from other network traffic
- Bandwidth efficiency is accomplished through segmenting traffic into smaller broadcast domains
- Easier add/move/delete administration of endpoints on a network and scalability for larger enterprise deployments
What is the Layer 2 Broadcast Destination Address? - correct answer
✅FFFF.FFFF. FFFF.
What is the Layer 3 Broadcast Destination Address? - correct answer
✅255.255.255.255.
What is VLAN 1 used for and can it be deleted? - correct answer ✅Management Traffic; it cannot be deleted
What is the normal VLAN range? - correct answer ✅VLAN 2 – 1001.
What is the extended VLAN range? - correct answer ✅VLAN 1006 – 4094.
What VLANs are auto-created and cannot be deleted? - correct answer
✅VLAN 1, 1002 - 1005
What VLANs cannot be pruned from a trunk? - correct answer ✅VLAN 1006
What will switch access ports do with am Ethernet frame it receives with an 802.1q tag? - correct answer ✅It will discard the packet without learning the source MAC address.
What command would you use to configure a range of switch ports? -
correct answer ✅interface range gigabitethernet#/# - #
What command lists all VLANs configured on a switch? - correct answer
✅show vlan or show vlan brief.
What command is used to display the switch ports assigned to a single
VLAN? - correct answer ✅show vlan id
When are data messages forwarded to the default gateway? - correct
answer ✅When the destination subnet is on a different subnet than the endpoint
Does the Cisco default switch configuration have an IP default gateway? -
correct answer ✅No
What command is used to create an IP default gateway? - correct answer
✅ip default-gateway <ip_address>
What is the primary purpose of a switch? - correct answer ✅To make forwarding decisions based on destination MAC address
List the network services provided by switches - correct answer ✅- Only read Ethernet frame headers and forward traffic
- Create and maintain the MAC address table
- Create separate collision domains per switch port
- Create separate broadcast domains per VLAN
What method was used for detecting Ethernet collisions on older hubs and bridges? - correct answer ✅Carrier Sense Multiple Access Collision Detection (CSMA/CD)
What are the steps when a host sends data to a server on the same VLAN for
the first time? - correct answer ✅1. Switch adds the source MAC address of incoming frame if it is not listed in the MAC address table
- Switch does a MAC address table lookup for the destination MAC address
- Switch floods a frame using FFFF.FFFF.FFFF as destination MAC address out all switch ports except the port where the source MAC address was learned
- Server wit the assigned MAC address responds with a frame that lists the MAC address
- Switch updates the MAC address table with the MAC address of the server; That is the destination MAC address for frames sent from the host
- Switch forwards the frames from the host to the server based on the switch port assigned to the server
What is Cut-Through Switching? - correct answer ✅It is a technique that optimizes performance by examing only the first 6 bytes (destination MAC address) of an Ethernet frame before making a forwarding decision. The switch does a MAC address table lookup for the destination MAC address and forwards the frame.
What is the advantage of Cut-Through Switching? - correct answer forwarding decision is made before all of the frame arrives and thereby minimizes latency
What is Store-and-Forward Switching? - correct answer ✅Traditional switching where the frame is not forwarded until all of the frame has arrived. The switch copies the frame to memory before examining the destination MAC address and forwarding the frame.
What is CEF? - correct answer ✅Cisco Express Forwarding: Layer 3 switching technique that creates FIB and adjacency tables for optimized forwarding. It is only available on routers and switch platforms with routing enabled and the required hardware
What is an FIB? - correct answer ✅Forwarding Information Base: Used by CEF to mae IP destination prefix-based switching decisions. Conceptually similar to a routing table or information base. It maintains a mirror image of the forwarding information contained in the IP routing table.
✅The
Why is it recommended to change the native VLAN? - correct answer ✅This is a Cisco security best practice as there are security vulnerabilities associated with default VLAN 1; STP issues are minimized as well by selecting a nondefault VLAN instead of VLAN 1
What command changes the native VLAN? - correct answer ✅switchport trunk native vlan <vlan_id>
What is the purpose of VLAN pruning? - correct answer ✅To permit or deny VLANs across a switch trunk
What is the Cisco default for VLAN pruning - correct answer ✅To allow all VLANs across the trunk
What command sets a range of VLANs to an interface? - correct answer
✅switchport trunk allowed vlan <#>-<#>
What are the three modes of DTP? - correct answer ✅nonegotiate, desirable, auto
Is DTP enabled by default on switch ports? - correct answer ✅Yes
What does a switch port configured with desirable mode do? - correct answer ✅Actively sends DTP frames to negotiate trunk with neighbor switch
What is the operation of switchport mode access? - correct answer
✅Access port only (no trunk) - only one VLAN, two if you include a Voice VLAN
What is the operation of switchport mode trunk? - correct answer ✅Trunk statically formed and no DTP frames sent
What is the operation of switchport mode dynamic auto? - correct answer
✅Listens for DTP requests
What is the operation of switchport mode dynamic desirable? - correct
answer ✅Listens and sends DTP requests
What are the advantages of EtherChannels? - correct answer ✅Fault tolerance (redundancy) and high speed connectivity between switches
What is the maximum number of ports Cisco switches support to a single
EtherChannel bundle? - correct answer ✅8 ports
What is the maximum number of ports LACP supports to a single EtherChannel bundle? - correct answer ✅16 ports, however only 8 ports can be active simultaneously
What is LACP? - correct answer ✅Link Aggregation Control Protocol, within the IEEE specification, provides a method of control the bundling of several physical ports together to form a single logical channel. It allows a network device to negotiate an automatic bundling of links by sending LACP packets to the peer
What are the options for configuring an EtherChannel? - correct answer
✅Static or Dynamic Protocols
What is the difference between static and dynamic EtherChannel configurations? - correct answer ✅Static does not provide any dynamic trunk negotiation
What are the four supported modes of LACP? - correct answer ✅On, off, active, and passive
What does the channel-group bind? - correct answer ✅The port channel interface to an EtherChannel
What is a Layer 2 port channel? - correct answer ✅Logical interface comprised of EtherChannel access ports or trunk ports
How is the Layer 2 port channel created? - correct answer ✅It is created automatically based on the channel-group number
What are the supported channel-group numbers? - correct answer ✅1 - 4096
What layer of the TCP/IP model does HTTP belong? - correct answer
✅Application Layer
What layer of the TCP/IP model does POP3 belong? - correct answer
✅Application Layer
What layer of the TCP/IP model does SMTP belong? - correct answer
✅Application Layer
What layer of the TCP/IP model does TCP and UDP belong? - correct answer
✅Transport Layer
What layer of the TCP/IP model does ICMP belong? - correct answer
✅Internet Layer
What does the Application Layer define? - correct answer ✅Does not define the applications itself, but it defines services that applications need.
The Application Layer provides an interface between software running on a computer and the network itself.
What does the return code 200 mean in an HTTP header? - correct answer
✅OK
What does the return code 404 mean in an HTTP header? - correct answer
✅Not found
What layers of the OSI model do not exist in the current TCP/IP model? -
correct answer ✅Session and Presentation Layers (5 and 6)
What standard is 802.3? - correct answer ✅Ethernet
In an Informal IEEE Standard Name, what does the T stand for (example:
1000BASE-T)? - correct answer ✅Unshielded Twisted Pair (UTP)
In an informal IEEE Standard Name, what does the X stand for (example:
1000BASE-LX)? - correct answer ✅Fiber
How many pairs does the 1000BASE-T require? - correct answer ✅4 pairs
What is a Gigabit Ethernet Interface Converter (GBIC)? - correct answer
✅Original form factor for a removable transceiver for Gigabit interfaces; larger than SFPs
What is a Small Form Pluggable (SFP)? - correct answer ✅Replacement for GBICs, used on Gigabit interfaces, with a smaller size, taking less space on the side of the networking card or switch
What is a Small Form Pluggable Plus (SFP+)? - correct answer ✅Same size as the SFP, but used on 10-Gbps interfaces
How many pairs of wires do the 10BASE-T and 100BASE-T use? - correct
answer ✅2 pairs
What pins do Ethernet NIC transmitters use? - correct answer ✅The pair connected to pins 1 and 2
What pins do Ethernet NIC receivers use? - correct answer ✅The pair connected to pins 3 and 6
What pins do Switch transmitters use? - correct answer ✅The pair connected to pins 3 and 6
What pins do Switch receivers use? - correct answer ✅The pair connected to pins 1 and 2
What cable would you use to connect a computer to a switch? - correct
answer ✅Straight through cable
What devices transmit on pins 3 and 6? - correct answer ✅Switches and Hubs
What devices transmit on pins 1 and 2? - correct answer ✅NICs, Routers, APs
