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Tüm alıştırma soruları

1987 soru

Tüm türler1,987Çoktan seçmeli1,020Çoklu seçim452Sayısal18Eşleştirme229Sıralama203Boşluk doldurma22Kısa cevap43
Soru 1021Soru →

A network engineer is evaluating cabling standards and optical transceiver specifications for a campus network refresh. When connecting switch interfaces across various media types, which two statements correctly describe physical interface and cabling characteristics according to Ethernet standards? (Select two.)

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: 10GBASE-SR transceivers operate over multimode fiber using an 850 nm wavelength and can reach up to 300 meters on OM3 cabling.; 1000BASE-T Ethernet requires all four wire pairs in Category 5e or higher UTP cabling to operate concurrently in full-duplex mode.

Cevap

The correct statements are that 10GBASE-SR transceivers operate over multimode fiber using an 850 nm wavelength reaching up to 300 meters on OM3 cabling, and 1000BASE-T Ethernet requires all four wire pairs in Category 5e or higher UTP cabling to operate concurrently.
10GBASE-SR transceivers specify short-wavelength 850 nm light over multimode fiber with standard distance caps of 300 meters on OM3 and 400 meters on OM4. Additionally, 1000BASE-T requires all four copper pairs in Cat5e or better cables, transmitting full-duplex signals over all eight conductors simultaneously.

Adım Adım Çözüm

1
Analyze optical fiber transceiver specifications
10GBASE-SR (Short Reach) uses 850 nm lasers over multimode fiber (MMF). It supports up to 300 m on laser-optimized OM3 MMF and 400 m on OM4 MMF.
Matching transceiver naming conventions (SR vs LR vs ER) to light wavelengths and distance limits is critical for optical link design.
2
Analyze twisted-pair copper transmission mechanics
1000BASE-T achieves 1 Gbps throughput across Category 5e/6 UTP by utilizing hybrid circuits that allow bi-directional transmission on all four pairs simultaneously.
10BASE-T and 100BASE-TX only use 2 pairs (4 wires), whereas Gigabit 1000BASE-T requires all 4 pairs (8 wires).
3
Evaluate and eliminate incorrect distractor claims regarding pinouts, fiber core diameters, and optic compatibility
Crossover cables swap pins 1/2 with pins 3/6. Single-mode fiber has a smaller core (9 microns) with no modal dispersion. 1000BASE-LX can run on MMF with a mode-conditioning patch cable.
Distinguishing between MMF and SMF physical attributes and recognizing optic deployment exceptions prevents physical layer design errors.

Anahtar Kavram

Physical Interface Standards and Cabling Specifications
Tahmini Süre:2m 0s
Soru 1022Soru →

When deriving an IPv6 64-bit interface identifier using the EUI-64 process from a 48-bit MAC address, which bit position (counted from left to right within the first octet) is inverted?

Cevabı ve açıklamayı göster

Cevap: 7; 7th; 7th bit; bit 7; seventh; seventh bit

Cevap

The 7th bit position (the Universal/Local bit) in the first octet of the MAC address is inverted.
During the EUI-64 calculation process, the 7th bit from the left of the MAC address's first octet (the Universal/Local bit) is inverted. For example, a universal MAC address starting with binary 00000000 (0x00) becomes 00000010 (0x02) after the 7th bit is flipped from 0 to 1.

Adım Adım Çözüm

1
Identify the modification rules for converting a 48-bit MAC address to an EUI-64 64-bit interface identifier.
The two required modifications are inserting the 16-bit value FFFEFFFE into the middle of the MAC address and inverting the Universal/Local (U/L) bit.
EUI-64 formatting requires extending the 48-bit MAC address to 64 bits and adjusting the scope indicator.
2
Determine the exact location of the Universal/Local (U/L) bit.
The U/L bit is located at the 7th bit position from the left in the first octet of the MAC address.
In standard IEEE MAC address formatting, bit 7 specifies whether the address is universally administered (0) or locally administered (1).

Anahtar Kavram

EUI-64 Universal/Local Bit Inversion
Soru 1023Soru →

A network engineer is configuring a newly installed Cisco Catalyst switch interface connected to a workstation. VLAN 40 does not currently exist in the switch VLAN database. The engineer enters the following CLI commands:

text
Switch(config)# interface GigabitEthernet1/0/4
Switch(config-if)# switchport mode access
Switch(config-if)# switchport access vlan 40

Which two outcomes occur immediately upon applying this configuration sequence? (Select two.)

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: VLAN 40 is automatically created and added to the switch VLAN database.; Interface GigabitEthernet1/0/4 is statically assigned to VLAN 40 and transmits untagged frames toward the connected workstation.

Cevap

The switch automatically creates VLAN 40 in the VLAN database, and interface GigabitEthernet1/0/4 is configured as an access port that transmits untagged Ethernet frames to the workstation.
Executing 'switchport access vlan 40' when VLAN 40 does not exist causes Cisco IOS to automatically create VLAN 40 in the VLAN database. Furthermore, configuring the interface with 'switchport mode access' assigns GigabitEthernet1/0/4 to VLAN 40 as a standard access port, which forwards untagged Ethernet frames to connected end-user hosts.

Adım Adım Çözüm

1
Analyze the automatic VLAN creation behavior in Cisco IOS CLI.
Executing 'switchport access vlan 40' when VLAN 40 is missing triggers dynamic creation of VLAN 40 in the VLAN database.
Cisco IOS prevents port isolation by automatically creating non-existent VLANs assigned to access ports.
2
Determine the framing behavior of an interface in access mode.
The interface operates as an access port in VLAN 40 and strips 802.1Q encapsulation from outgoing frames.
End-user hosts expect standard untagged Ethernet frames rather than 802.1Q tagged frames.

Anahtar Kavram

Cisco IOS dynamic VLAN creation and access port framing mechanics
Soru 1024Soru →

A network administrator checks the operational state of link GigabitEthernet0/1 connecting two switches, SW-Core and SW-Access. Both switch interfaces are operating with default factory switchport settings, which sets their Dynamic Trunking Protocol (DTP) mode to dynamic auto. Which two outcomes describe the state of this connection? (Select two.)

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: The interface operationally functions as a Layer 2 access port in VLAN 1.; To establish an active trunk connection using dynamic negotiation, at least one interface must be configured as dynamic desirable.

Cevap

The interface operationally functions as a Layer 2 access port in VLAN 1, and establishing a trunk via dynamic negotiation requires at least one interface to be set to dynamic desirable.
When both ends of a switch-to-switch link operate in default dynamic auto mode, neither switch interface sends DTP negotiation packets to initiate a trunk. Consequently, the operational status of both ports remains in access mode operating in the default VLAN 1. For dynamic trunking negotiation to succeed, at least one of the connected interfaces must actively request a trunk by being configured in dynamic desirable mode.

Adım Adım Çözüm

1
Analyze the default Cisco Dynamic Trunking Protocol (DTP) mode settings.
Both interfaces on SW-Core and SW-Access are in dynamic auto mode.
Dynamic auto mode listens for DTP frame requests but never actively initiates trunk negotiation.
2
Evaluate the DTP negotiation state table for auto-to-auto connections.
The link fails to form a trunk and defaults to access operational state.
Since neither side sends DTP trunking requests, the negotiation stays passive and defaults to access mode.
3
Determine the necessary configuration changes to form a dynamic trunk.
At least one side must be switched to dynamic desirable (or statically set to trunk).
Dynamic desirable actively sends DTP packets to request trunk negotiation from the opposing dynamic auto switch port.

Anahtar Kavram

DTP mode negotiation combinations and operational defaults for 802.1Q trunks
Soru 1025Soru →

A network administrator is evaluating transport layer protocol characteristics for two distinct enterprise applications: a database replication service requiring guaranteed in-order data transfer, and a emergency voice alert system prioritizing minimum transmission delay. Which statements correctly distinguish how TCP and UDP support these requirements? (Select TWO.)

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Cevabı ve açıklamayı göster

Cevap: TCP utilizes sequence numbers and acknowledgments to ensure reliable, ordered byte-stream delivery for data replication.; UDP operates with a fixed 8-byte header and avoids connection handshake latency, making it suitable for real-time voice delivery.

Cevap

TCP guarantees reliable in-order delivery using sequence numbers and acknowledgments, while UDP provides low overhead with an 8-byte header and connectionless transmission ideal for latency-sensitive applications.
TCP is connection-oriented and uses sequence numbers along with acknowledgment numbers to track stream state and guarantee in-order delivery. Conversely, UDP is connectionless and lightweight, utilizing a small 8-byte header to eliminate transmission overhead for latency-sensitive traffic such as voice broadcasts.

Adım Adım Çözüm

1
Analyze transport protocol requirements for the database replication service.
Database replication requires absolute data accuracy, loss detection, and in-order delivery, which demands TCP features like sequencing, ACKs, and retransmission.
Data integrity takes priority over transport latency.
2
Analyze transport protocol requirements for the voice alert system.
Voice traffic is sensitive to delay and jitter but can tolerate minor packet loss, making UDP the ideal choice due to its low 8-byte overhead and lack of handshake delays.
Connectionless best-effort delivery prevents head-of-line blocking.
3
Evaluate protocol features against provided options.
The options describing TCP sequencing/ACK reliability mechanics and UDP minimal 8-byte header/connectionless operation accurately state protocol behaviors.
Flow control and connectionless bulk transfer assertions misplace TCP and UDP mechanics.

Anahtar Kavram

TCP vs UDP Characteristics and Header Comparison
Soru 1026Soru →

An administrator is configuring a switch management VLAN interface with an IPv4 address of 172.16.5.33 and a subnet mask of 255.255.255.224 (/27). What is the total number of usable host IP addresses available on this subnet?

Cevabı ve açıklamayı göster

Cevap: 30

Cevap

The total number of usable host IP addresses available on a /27 subnet is 30.
The correct answer is 30. For a prefix of /27 (subnet mask 255.255.255.224), there are 32−27=532 - 27 = 5 host bits available. The total address block size is 25=322^5 = 32. Subtracting the network identifier and the broadcast address (32−232 - 2) gives exactly 30 usable host IP addresses.

Adım Adım Çözüm

1
Determine the number of host bits from the prefix length.
32 total IPv4 address bits - 27 network bits = 5 host bits (n=5n = 5).
The prefix length /27 defines 27 bits for the network portion, leaving the remaining bits for host addressing.
2
Calculate the total number of IP addresses in the subnet block.
25=322^5 = 32 total IP addresses.
The formula 2n2^n calculates the total number of binary combinations available with nn host bits.
3
Subtract the non-assignable network and broadcast addresses to find the usable host count.
32−2=3032 - 2 = 30 usable host IP addresses.
In standard IPv4 subnetting, the first address (network ID) and last address (directed broadcast address) cannot be assigned to individual hosts.

Anahtar Kavram

Calculating Usable IPv4 Host Addresses using the 2n−22^n - 2 Formula
Tahmini Süre:45s
Soru 1027Soru →

Network administrators must understand the key attributes, IEEE standards, and default operational parameters of Layer 2 discovery protocols when configuring enterprise switches. Match each Layer 2 discovery protocol characteristic on the left with its corresponding protocol specification or value on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

IEEE 802.1AB
CDP Default Advertisement Interval
LLDP Default Holdtime
Cisco Discovery Protocol (CDP)

Eşleşmeler

Cevabı ve açıklamayı göster

Cevap

IEEE 802.1AB matches the open IEEE standard defining LLDP; CDP Default Advertisement Interval matches 60 seconds; LLDP Default Holdtime matches 120 seconds; Cisco Discovery Protocol (CDP) matches the Cisco-proprietary Layer 2 discovery protocol enabled by default on Cisco Catalyst switches.
Each item accurately corresponds to its defining standard, default timer, or vendor status. IEEE 802.1AB specifies LLDP; CDP advertises every 60 seconds; LLDP retains neighbor entries for a default holdtime of 120 seconds (30s x 4); and CDP is a Cisco-proprietary protocol enabled out of the box.

Adım Adım Çözüm

1
Identify the standard specification for LLDP
IEEE 802.1AB defines vendor-neutral LLDP
Standardization allows multi-vendor interoperability for discovery protocols.
2
Determine default CDP update interval
CDP transmits periodic updates every 60 seconds by default
Cisco IOS uses 60 seconds for update packets and 180 seconds for holdtime.
3
Calculate default LLDP holdtime value
LLDP transmit timer (30s) multiplied by holdtime multiplier (4) equals 120 seconds
LLDP calculates holdtime dynamically based on transmit frequency and multiplier.
4
Identify proprietary characteristics of CDP
CDP is Cisco-proprietary and active by default on Cisco hardware
Unlike LLDP, CDP does not require global enablement on standard Cisco switch platforms.

Anahtar Kavram

Layer 2 Discovery Protocols (CDP and LLDP) Timers and Standards
Tahmini Süre:1m 0s
Soru 1028Soru →

A network administrator needs to establish a routed (Layer 3) EtherChannel between two Cisco switches using LACP active mode across physical interfaces GigabitEthernet0/1 and GigabitEthernet0/2. In what correct chronological order should the administrator execute the Cisco IOS CLI commands to configure this Layer 3 EtherChannel from global configuration mode?

Öğeleri doğru sıraya koymak için sürükleyin

Cevabı ve açıklamayı göster

Cevap

The correct configuration order requires selecting physical member interfaces first, converting them to Layer 3 routed ports using 'no switchport', assigning them to EtherChannel group 10 with LACP active mode, entering Port-channel 10 configuration mode, and finally configuring the IPv4 address on the logical Port-channel interface.
The correct order follows Cisco standard CLI logic for Layer 3 EtherChannel configuration: select physical member interfaces ('interface range GigabitEthernet0/1 - 2'), convert them to routed ports ('no switchport'), form the LACP EtherChannel bundle ('channel-group 10 mode active'), navigate into the logical interface ('interface Port-channel 10'), and assign the IP address ('ip address 10.10.10.1 255.255.255.252').

Adım Adım Çözüm

1
Select physical member interfaces
Entered interface range configuration mode for GigabitEthernet0/1 - 2.
CLI commands must be applied to physical interfaces first before grouping them into a bundle.
2
Execute 'no switchport' on physical member interfaces
Member interfaces are converted from Layer 2 switch ports to Layer 3 routed ports.
A Layer 3 EtherChannel requires member interfaces to be configured as routed interfaces before establishing the channel group.
3
Execute 'channel-group 10 mode active'
Physical interfaces are added to Port-channel 10 under LACP active negotiation mode.
The channel-group command dynamically creates the Port-channel interface with LACP protocol.
4
Enter logical interface mode via 'interface Port-channel 10'
Router moves into logical interface configuration prompt.
Layer 3 configurations (IP addressing) must be defined on the logical port-channel interface itself.
5
Apply IP address parameters on Port-channel 10
IP address 10.10.10.1/30 is bound to Port-channel 10.
Traffic routing across Layer 3 EtherChannel uses the logical interface IP address.

Anahtar Kavram

Layer 3 EtherChannel CLI configuration workflow requires setting 'no switchport' on physical member interfaces prior to creating the channel-group and applying IP addressing on the logical Port-channel interface.
Soru 1029Soru →

A network administrator is inspecting intra-host traffic flows within a Type 1 hypervisor environment. Two virtual machines, VM-A and VM-B, reside on the same physical host and are attached to the same VLAN configured on a virtual switch (vSwitch). When VM-A transmits Ethernet frames destined for VM-B, how does the hypervisor handle the frame forwarding?

Cevabı ve açıklamayı göster

Cevap: The vSwitch performs Layer 2 forwarding entirely in software within host memory, delivering the frames directly to VM-B without sending them out the physical Network Interface Card (pNIC).

Cevap

The vSwitch performs Layer 2 forwarding entirely in software within host memory, delivering the frames directly to VM-B without sending them out the physical Network Interface Card (pNIC).
When virtual machines reside on the same physical host and are attached to the same VLAN on a vSwitch, the vSwitch performs Layer 2 frame switching entirely within host memory. The frames move directly between virtual ports (vNICs) via hypervisor software, so traffic does not exit out to physical network interface cards (pNICs) or external switches.

Adım Adım Çözüm

1
Identify the location of the source VM, destination VM, and virtual network configuration.
Both VM-A and VM-B reside on the same physical host and belong to the same VLAN on the internal vSwitch.
Traffic flow destination analysis determines whether physical media must be traversed.
2
Analyze how a virtual switch (vSwitch) operates inside a bare-metal hypervisor.
The vSwitch maintains an internal software MAC address table mapping virtual ports to VM vNIC MAC addresses.
A vSwitch functions like a physical Layer 2 switch, but forwarding occurs via system RAM and bus operations inside the hypervisor.
3
Determine physical network interface card (pNIC) involvement.
Since both virtual interfaces are internal to the host on the same vSwitch and VLAN, frame switching occurs completely within host memory without utilizing uplink pNICs.
Uplink pNICs are only required when traffic is destined for devices outside the physical host.

Anahtar Kavram

Virtual switch (vSwitch) intra-host frame forwarding mechanics
Tahmini Süre:1m 0s
Soru 1030Soru →

An organization is deploying a dedicated network segment for industrial control systems. The network team needs to enforce deep packet inspection, application-level policy enforcement, and threat prevention between this industrial segment and the corporate intranet. Which network component is best suited to perform these specific security functions at the boundary?

Cevabı ve açıklamayı göster

Cevap: Next-Generation Firewall (NGFW)

Cevap

Next-Generation Firewall (NGFW)
A Next-Generation Firewall (NGFW) integrates traditional stateful firewall capabilities with Layer 7 application inspection, intrusion prevention systems (IPS), and threat protection, making it the appropriate choice to protect boundaries between different functional network zones.

Adım Adım Çözüm

1
Analyze the operational requirements specified in the scenario
The requirement identifies deep packet inspection, application-level security enforcement, and threat mitigation between two network zones.
Security functions above Layer 3 require specialized appliances capable of inspecting traffic payloads beyond basic header routing.
2
Evaluate the capabilities of network components at boundary points
Next-Generation Firewalls combine stateful inspection with advanced services like application control and intrusion prevention.
Deploying an NGFW at the network boundary ensures policy control and threat protection for incoming and outgoing segment traffic.

Anahtar Kavram

Network Security Appliance Roles (NGFW vs. L2 Devices & Hypervisors)
Soru 1031Soru →

A network administrator is troubleshooting an inter-switch link failure between Switch-1 and Switch-2. Switch-1 is configured for a Layer 3 EtherChannel, but the bundle fails to form, and Switch-2 is unable to route traffic across the link.

On Switch-1, the relevant configuration is:
text
interface Port-channel 5
ip address 10.10.50.1 255.255.255.252
!
interface range GigabitEthernet0/1 - 2
no switchport
channel-group 5 mode active

On Switch-2, the administrator issues the `show etherchannel 5 summary` command, which displays the following output:
text Flags: D - down P - bundled in port-channel I - stand-alone s - suspended H - Hot-standby s - Layer2 U - in use R - Layer3 S - Layer2 F - failed to allocate aggregator Group Port-channel Protocol Ports ------+------------+----------+----------------------------------------------- 5 Po5(SD) LACP Gi0/1(I) Gi0/2(I)

Additionally, inspecting `show running-config interface GigabitEthernet0/1` on Switch-2 reveals:
text
interface GigabitEthernet0/1
channel-group 5 mode passive

Which condition is the primary root cause of Switch-2 placing GigabitEthernet0/1 and GigabitEthernet0/2 into stand-alone `(I)` state and Port-channel 5 into Switch-port Down `(SD)` state?

Cevabı ve açıklamayı göster

Cevap: Switch-2 member interfaces are operating as default Layer 2 ports because `no switchport` was omitted on the physical member interfaces prior to or after adding them to the port-channel.

Cevap

Switch-2 member interfaces are operating as default Layer 2 ports because `no switchport` was omitted on the physical member interfaces prior to or after adding them to the port-channel.
For a Layer 3 EtherChannel to aggregate properly, both switches must configure physical member ports and logical port-channel interfaces with the `no switchport` command. Switch-1 configured member interfaces as routed ports, while Switch-2 retained default Layer 2 behavior (indicated by the `S` flag in `Po5(SD)`). Because Layer 2 ports cannot bundle with Layer 3 ports across LACP peers, Switch-2 falls back to placing its physical interfaces into stand-alone `(I)` mode.

Adım Adım Çözüm

1
Analyze the Switch-1 configuration
Switch-1 explicitly executes `no switchport` on physical interfaces GigabitEthernet0/1 and GigabitEthernet0/2 and sets `channel-group 5 mode active` to create a routed (Layer 3) LACP EtherChannel.
Layer 3 EtherChannels require physical interfaces to operate in unswitched (routed) mode.
2
Inspect the CLI output flags on Switch-2
Flag `S` indicates Layer 2 operational mode and flag `D` indicates Down for `Po5(SD)`. Flag `I` indicates Stand-alone state for `Gi0/1(I)` and `Gi0/2(I)`.
When physical interfaces remain in default Layer 2 mode (`switchport`) while the peer switch expects Layer 3 routed interfaces, parameter mismatches prevent LACP bundle aggregation, forcing member ports into stand-alone state.
3
Evaluate LACP operational compatibility
LACP negotiation requires consistent Layer 2/Layer 3 port characteristics between peer switches.
To resolve the issue, Switch-2 must execute `no switchport` on both physical interfaces and `interface Port-channel 5`.

Anahtar Kavram

Layer 3 EtherChannel Member Interface Requirements
Soru 1032Soru →

A network administrator enters the command `ipv6 address 2001:db8:1111:2222::/64 eui-64` on a Cisco router interface. If the MAC address of the interface is `1422.db88.99aa`, which IPv6 address will be automatically configured on the interface?

Cevabı ve açıklamayı göster

Cevap: 2001:db8:1111:2222:1622:dbff:fe88:99aa

Cevap

The IPv6 address automatically configured on the interface is 2001:db8:1111:2222:1622:dbff:fe88:99aa.
The correct option demonstrates the precise three-step EUI-64 calculation process: splitting MAC address 1422.db88.99aa into two 24-bit halves, inserting FFFE in the center to form 64 bits, and flipping the seventh bit of the first byte (converting 0x14 to 0x16), resulting in 2001:db8:1111:2222:1622:dbff:fe88:99aa.

Adım Adım Çözüm

1
Split the 48-bit MAC address into two 24-bit halves.
First half: 14-22-DB, Second half: 88-99-AA.
EUI-64 formatting requires inserting a 16-bit delimiter into the center of a standard 48-bit MAC address.
2
Insert the hex value FFFE between the two halves.
1422:DBFF:FE88:99AA.
FFFE is the standard 16-bit field inserted to expand a 48-bit MAC to a 64-bit interface identifier.
3
Invert the 7th bit (Universal/Local bit) of the first byte.
Hex 14 (binary 00010100) becomes Hex 16 (binary 00010110), yielding the interface ID 1622:dbff:fe88:99aa.
The IEEE EUI-64 standard flips the 7th bit of the OUI to represent universal scope when derived from a MAC address.
4
Combine the /64 IPv6 prefix with the calculated 64-bit interface ID.
2001:db8:1111:2222:1622:dbff:fe88:99aa.
The full 128-bit IPv6 address is constructed by appending the EUI-64 interface ID to the assigned prefix.

Anahtar Kavram

Modified EUI-64 Interface Identifier Generation
Soru 1033Soru →

A network technician is installing a new backbone link between two network switches located in separate campus buildings that are 2 kilometers apart. The project specification requires a Gigabit Ethernet connection over fiber-optic cabling. Which combination of optical transceiver standard and fiber cabling type must be selected to support this link?

Cevabı ve açıklamayı göster

Cevap: 1000BASE-LX transceiver with Single-Mode Fiber (SMF)

Cevap

1000BASE-LX transceiver with Single-Mode Fiber (SMF)
The combination of a 1000BASE-LX transceiver and Single-Mode Fiber (SMF) is designed for long-wavelength laser transmission over long distances, supporting Gigabit Ethernet reaches up to 5 km. This fully covers the required 2-kilometer span.

Adım Adım Çözüm

1
Identify the required bandwidth and distance specs.
The requirement specifies Gigabit Ethernet (1000 Mbps) over a distance of 2 kilometers.
Choosing physical layer optics requires matching speed rating and distance limitations.
2
Evaluate candidate Ethernet transceiver standards against the 2 km requirement.
1000BASE-LX over Single-Mode Fiber supports Gigabit speeds up to 5 km, whereas 1000BASE-SX maxes out at 550m and copper 1000BASE-T maxes out at 100m.
Single-mode fiber features a tiny core (9μm9\mu m) that minimizes modal dispersion over long distances.

Anahtar Kavram

Gigabit Ethernet Fiber Transceiver Specifications (1000BASE-LX vs 1000BASE-SX)
Soru 1034Soru →

A network administrator needs to create VLAN 20 on a Cisco Catalyst switch and configure interface GigabitEthernet0/1 as an access port belonging to VLAN 20. Arrange the CLI commands in the correct sequence, starting from privileged EXEC mode.

Öğeleri doğru sıraya koymak için sürükleyin

Cevabı ve açıklamayı göster

Cevap

The correct CLI configuration sequence begins by entering global configuration mode with 'configure terminal', creating the VLAN with 'vlan 20', navigating to the target interface with 'interface GigabitEthernet0/1', defining static access mode via 'switchport mode access', and finally binding the interface to the VLAN using 'switchport access vlan 20'.
The configuration progression follows Cisco IOS hierarchical logic: enter global configuration mode ('configure terminal'), create the VLAN in the database ('vlan 20'), transition to the specific interface context ('interface GigabitEthernet0/1'), force the link to operate as an access link ('switchport mode access'), and assign it to the desired broadcast domain ('switchport access vlan 20').

Adım Adım Çözüm

1
Enter global configuration mode
Switch prompt changes to Switch(config)#
Global configuration mode is required before creating VLANs or specifying interface configurations.
2
Create VLAN 20
VLAN 20 is added to the database and prompt changes to Switch(config-vlan)#
Creating the VLAN ensures the broadcast domain exists prior to assigning switch ports to it.
3
Enter interface configuration mode for GigabitEthernet0/1
Switch prompt changes to Switch(config-if)#
Interface parameters must be configured within the specific interface configuration context.
4
Configure static access mode on the interface
Disables DTP trunk negotiation and sets interface to access mode
Explicitly declaring access mode ensures the port will not form a trunk link.
5
Assign the interface to VLAN 20
Interface GigabitEthernet0/1 is placed into VLAN 20
Associates untagged layer 2 traffic on GigabitEthernet0/1 with broadcast domain VLAN 20.

Anahtar Kavram

Cisco IOS CLI hierarchy for VLAN creation and switchport access assignment
Soru 1035Soru →

A network administrator is verifying a newly deployed link aggregation bundle between Switch-A and Switch-B. The command `show etherchannel summary` on Switch-A displays Port-channel 5 as `Po5(SD)` with member interfaces `GigabitEthernet1/0/1(I)` and `GigabitEthernet1/0/2(I)` running protocol `LACP`. On Switch-B, `show etherchannel summary` displays `Po5(SD)` with member interfaces `GigabitEthernet1/0/1(I)` and `GigabitEthernet1/0/2(I)` running protocol `PAgP`.

Which TWO statements accurately describe why Port-channel 5 fails to bundle and remains in a down state?

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: Switch-A and Switch-B are running conflicting EtherChannel negotiation protocols, which prevents dynamic link aggregation setup.; Switch-B physical interfaces were configured with `channel-group 5 mode auto` or `channel-group 5 mode desirable`, which explicitly selects PAgP instead of LACP.

Cevap

The bundle fails because Switch-A and Switch-B are configured with mismatched EtherChannel protocols (LACP vs. PAgP), caused by Switch-B using `channel-group 5 mode auto` or `mode desirable`.
EtherChannel requires both endpoints to run the same aggregation protocol. Switch-A is configured for LACP (via `mode active` or `mode passive`), whereas Switch-B is configured for PAgP (via `mode auto` or `mode desirable`). Because LACP and PAgP control frames are incompatible, negotiation fails, leaving member interfaces in standalone state `(I)` and the port-channel down `(SD)`.

Adım Adım Çözüm

1
Analyze the `show etherchannel summary` protocol column for Switch-A and Switch-B.
Switch-A displays protocol `LACP`, while Switch-B displays protocol `PAgP`.
LACP and PAgP use completely different control frame formats and state machines, making them mutually incompatible.
2
Evaluate the interface CLI configuration that causes Switch-B to run PAgP.
Switch-B member interfaces were assigned using PAgP mode commands (`channel-group 5 mode auto` or `channel-group 5 mode desirable`).
To operate with LACP, Switch-B member interfaces must be configured using `channel-group 5 mode active` or `channel-group 5 mode passive`.
3
Verify flags `(SD)` and `(I)` in the command output.
`S` indicates Layer 2, `D` indicates Down, and `I` indicates Standalone mode.
Because protocol negotiation fails, member interfaces drop to standalone `(I)` mode and the port-channel interface stays down `(SD)`.

Anahtar Kavram

Layer 2 EtherChannel LACP vs. PAgP Protocol Compatibility and CLI Mode Selection
Soru 1036Soru →

A network engineer is setting up a dynamic Layer 2 EtherChannel between Switch-A and Switch-B using the Link Aggregation Control Protocol (LACP). Switch-A is configured on its member interfaces with `channel-group 10 mode active`. The engineer wants Switch-B to form the EtherChannel by only responding to incoming LACP negotiation requests without actively sending initial negotiation frames. Which command should be applied to Switch-B's member interfaces?

Cevabı ve açıklamayı göster

Cevap: channel-group 10 mode passive

Cevap

The correct command is `channel-group 10 mode passive` because LACP passive mode responds to incoming LACP negotiation packets sent by an LACP active peer without actively initiating LACP frame transmissions.
The command `channel-group 10 mode passive` configures the interface to use LACP in a passive role. When connected to a device in LACP active mode (such as Switch-A), the passive interface receives the active LACP frames, responds to them, and successfully forms an EtherChannel bundle.

Adım Adım Çözüm

1
Identify the protocol in use on Switch-A.
Switch-A uses `channel-group 10 mode active`, which identifies IEEE 802.3ad LACP in active negotiation mode.
EtherChannel negotiation protocols must match on both ends (LACP to LACP).
2
Determine the required operating mode for Switch-B.
Switch-B must operate in LACP passive mode.
LACP passive mode waits to receive LACP packets and responds to them, allowing the bundle to form when paired with an active peer.
3
Evaluate protocol options to select the correct CLI command.
`channel-group 10 mode passive` matches the exact requirement for LACP passive behavior.
Modes such as `auto` and `desirable` use PAgP instead of LACP, and `on` disables dynamic protocol negotiation completely.

Anahtar Kavram

LACP EtherChannel Mode Compatibility and Operation
Soru 1037Soru →

A network administrator is configuring a secure interswitch 802.1Q trunk link on Cisco switch interface GigabitEthernet0/1. The task requires statically enabling trunking, stopping DTP frame negotiation, reassigning the native VLAN to VLAN 99, and removing VLAN 1 from the trunk's allowed list. Place the CLI commands and actions in the correct logical configuration order.

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Cevap

The correct sequence begins by entering interface mode, enforcing static trunking, disabling DTP negotiation, setting native VLAN 99, and finally removing VLAN 1 from the allowed VLAN list.
Configuring a static 802.1Q trunk on a Cisco Catalyst switch requires stepping into interface configuration mode first. Setting switchport mode trunk must precede switchport nonegotiate because DTP disabling is rejected by Cisco IOS on dynamic interfaces. Configuring native VLAN 99 and pruning VLAN 1 completes the trunk hardening workflow.

Adım Adım Çözüm

1
Execute interface GigabitEthernet0/1 in global configuration mode.
Enters interface configuration context.
Port configuration parameters must be applied within the specific interface context.
2
Execute switchport mode trunk.
Sets administrative state to unconditional trunking.
Cisco IOS requires an explicit static mode (trunk or access) prior to issuing switchport nonegotiate.
3
Execute switchport nonegotiate.
Stops transmission of DTP frames.
Prevents unauthorized trunk negotiation while ensuring the link remains statically operational.
4
Execute switchport trunk native vlan 99.
Configures VLAN 99 as the native untagged VLAN.
Overrides default VLAN 1 untagged frame behavior to prevent security issues such as VLAN hopping.
5
Execute switchport trunk allowed vlan remove 1.
Removes VLAN 1 from the trunk forwarding topology.
Ensures default management VLAN traffic does not traverse the interswitch link.

Anahtar Kavram

802.1Q Trunk CLI Configuration Order and DTP Prerequisites
Soru 1038Soru →

During the dynamic creation of an IPv6 interface identifier using the EUI-64 method, a 48-bit MAC address is split into two equal 24-bit halves. Which 16-bit hexadecimal value is inserted directly between these two halves?

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Cevap: FFFE

Cevap

FFFE
The standard IEEE EUI-64 process expands a 48-bit MAC address into a 64-bit interface identifier by inserting the specific 16-bit hexadecimal value FFFE directly into the center between the first 24 bits (OUI) and the last 24 bits (NIC specific extension), followed by inverting the 7th bit (Universal/Local bit).

Adım Adım Çözüm

1
Identify the MAC address splitting point
The 48-bit MAC address is divided into two 24-bit (3-byte) halves.
EUI-64 requires extending a 48-bit MAC address to a 64-bit length by inserting 16 bits in the middle.
2
Determine the inserted hexadecimal value
The 16-bit hexadecimal value FFFE is inserted between the two 24-bit halves.
By standard definition (RFC 4291), FFFE expands the 48-bit MAC address to 64 bits.

Anahtar Kavram

EUI-64 Interface Identifier Derivation
Soru 1039Soru →

An administrator on Switch-A attempts to add VLAN 40 to an operational IEEE 802.1Q trunk interface currently forwarding traffic for VLANs 10, 20, and 30. The administrator executes the command `switchport trunk allowed vlan 40` in interface configuration mode. Immediately after, users in VLANs 10, 20, and 30 lose connectivity across the trunk link. Which command should the administrator have executed to add VLAN 40 without disrupting existing VLAN traffic?

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Cevap: switchport trunk allowed vlan add 40

Cevap

The administrator should use the command 'switchport trunk allowed vlan add 40'.
In Cisco IOS, executing `switchport trunk allowed vlan <ids>` overwrites the existing list of allowed VLANs on a trunk interface. To preserve existing allowed VLANs while adding a new VLAN, the `add` keyword must be explicitly included.

Adım Adım Çözüm

1
Analyze the impact of the executed command 'switchport trunk allowed vlan 40'.
Executing 'switchport trunk allowed vlan 40' replaces the entire trunk allowed list with only VLAN 40, removing VLANs 10, 20, and 30 from being allowed across the link.
Omitting parameter modifiers causes Cisco IOS to completely overwrite the current allowed VLAN list with the specified list.
2
Determine the correct Cisco IOS command syntax to append a VLAN to an active trunk allowed list.
The correct command syntax is 'switchport trunk allowed vlan add 40'.
The 'add' keyword instructs the switch to append VLAN 40 to the existing list rather than replacing it.

Anahtar Kavram

802.1Q Trunk Allowed VLAN Modification
Tahmini Süre:1m 0s
Soru 1040Soru →

An enterprise network infrastructure relies on dedicated hardware devices to perform specialized functions across the network topology. Match each network component on the left to its primary operational role on the right.

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Öğeler

Router
Layer 2 Switch
Next-Generation Firewall (NGFW)
Wireless LAN Controller (WLC)

Eşleşmeler

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Cevap

Router matches with evaluating packet headers against a routing table to forward traffic between Layer 3 networks and isolate broadcast domains; Layer 2 Switch matches with making frame forwarding decisions based on destination MAC addresses while isolating collision domains; Next-Generation Firewall matches with providing stateful packet inspection and application-level threat prevention; Wireless LAN Controller matches with centralizing management and RF control across lightweight access points.
Each network component is paired according to its core architectural role in an enterprise network: Routers perform Layer 3 forwarding and broadcast isolation; Layer 2 Switches perform MAC-based switching within a local broadcast domain; NGFWs enforce boundary security and application awareness; WLCs manage lightweight access points and radio frequencies centrally.

Adım Adım Çözüm

1
Analyze the primary operation of a Router
Identified as a Layer 3 device that routes between IP networks and terminates broadcast domains.
Routers forward packets using destination IP addresses and routing table lookups.
2
Analyze the primary operation of a Layer 2 Switch
Identified as a Layer 2 device that switches Ethernet frames using MAC address tables.
Switches separate collision domains on each physical interface within a single broadcast domain.
3
Analyze the primary operation of a Next-Generation Firewall (NGFW)
Identified as a security component providing stateful inspection and deep packet/application monitoring.
NGFWs go beyond basic Layer 3/4 ACLs by inspecting Layer 7 application payloads and threats.
4
Analyze the primary operation of a Wireless LAN Controller (WLC)
Identified as a centralized management device for lightweight access points (LAPs).
WLCs handle control plane activities, radio frequency (RF) management, and LAP provisioning via CAPWAP.

Anahtar Kavram

Enterprise Network Components and Functional Roles
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