AP Networking ARP and Address Conflicts Practice Test

1. ICMP echo alone
2. DHCP address allocation
3. DNS address lookup
4. ARP

Correct answer: D. ARP

ARP maps an on-link IPv4 address to a link-layer address. DNS resolves names and DHCP supplies configuration; neither replaces that neighbor lookup.

1. The resolver's MAC regardless of next hop
2. The local gateway interface's MAC address
3. The client's own MAC as destination
4. The remote endpoint's MAC regardless of route

Correct answer: B. The local gateway interface's MAC address

The Ethernet destination is the local next hop. The IP destination can remain the remote server while the frame targets the gateway.

1. Through every IP router unchanged
2. As a unicast to the unknown target MAC
3. As a TCP connection to the remote application
4. As a broadcast on the local broadcast domain

Correct answer: D. As a broadcast on the local broadcast domain

The broadcast asks local participants about the target IPv4 address. Ordinary routing does not carry that ARP request to a remote broadcast domain.

1. Hostname-to-address answer lifetimes
2. IPv4-to-link-layer neighbor mappings
3. MAC-to-switchport locations
4. TCP-port-to-listener associations

Correct answer: B. IPv4-to-link-layer neighbor mappings

The cache stores neighbor resolution information for local forwarding. It is distinct from DNS, sockets and switch configuration.

1. IPv4 addresses with DNS lifetimes
2. MAC addresses with forwarding ports in the relevant VLAN context
3. IPv4 addresses with peer MACs
4. Transport sockets with user identities

Correct answer: B. MAC addresses with forwarding ports in the relevant VLAN context

A switch learns source MAC locations and uses destination MAC lookup for forwarding. That table is not the host's ARP cache.

1. A short MAC aging timer only
2. A missing default route by definition
3. A duplicate IPv4 address
4. A duplicate DNS alias only

Correct answer: C. A duplicate IPv4 address

Independent endpoints using the same unicast address can produce conflicting neighbor mappings and misdelivery. Intentional shared service designs need explicit supported mechanisms.

1. ARP must balance the two endpoints evenly
2. The switch merges both endpoints into one service
3. DNS guarantees only one claimant can answer
4. Neighbor mappings may change between competing claimants

Correct answer: D. Neighbor mappings may change between competing claimants

Which MAC a sender associates with the address can vary with observed messages and cache state. Intermittence does not make the duplicate harmless.

1. Only the hostname printed in inventory
2. Sender protocol address and sender hardware address, with time and capture context
3. Only the target protocol address without the sender claim
4. Only the outer frame length

Correct answer: B. Sender protocol address and sender hardware address, with time and capture context

The sender fields advertise the claimed IPv4-to-MAC binding. Time and observation point are needed to compare competing claims.

1. A neighbor-resolution response was received for that local gateway address
2. Every remote service path works
3. The user is authorized for the remote resource
4. The intended web certificate is valid

Correct answer: A. A neighbor-resolution response was received for that local gateway address

Neighbor resolution is one local prerequisite. Routing, policy and application behavior remain separate checks.

1. Updating the switchport VLAN
2. Renewing a current server lease
3. Publishing a forward A record
4. Checking whether an address appears in use before claiming it

Correct answer: D. Checking whether an address appears in use before claiming it

A probe checks a candidate address for conflict. It is not an address allocation or an application test.

1. The candidate address in every initial probe
2. 255.255.255.255
3. The configured gateway address
4. 0.0.0.0

Correct answer: D. 0.0.0.0

A probe uses a zero sender protocol address while targeting the proposed address. An announcement has a different ownership-signaling role.

1. Create an authoritative address record
2. Advertise the host's IPv4-to-MAC association on the local link
3. Verify every peer's application identity
4. Request a DHCP lease extension

Correct answer: B. Advertise the host's IPv4-to-MAC association on the local link

Announcements help peers learn an association and can reveal conflicts. They do not publish DNS or create application services.

1. To locate the actual endpoint claiming an address
2. It proves the endpoint cannot move later
3. It replaces every packet timestamp
4. It permanently reserves the IP in DNS

Correct answer: A. To locate the actual endpoint claiming an address

Address configuration is easier to verify when tied to a physical or virtual endpoint and attachment. A name label alone may be stale.

1. A transport connection has completed
2. A lease extension has been acknowledged
3. DNS returned a name error
4. Resolution has not produced a usable neighbor binding yet

Correct answer: D. Resolution has not produced a usable neighbor binding yet

An incomplete neighbor entry concerns link-layer resolution. Determine whether requests leave and whether the target or next hop can reply.

1. ARP must precede every individual IP packet
2. The cached state guarantees the application is running
3. It already has a usable cached neighbor mapping
4. The peer must therefore be off-subnet

Correct answer: C. It already has a usable cached neighbor mapping

A usable cache avoids repeating resolution for every packet. Observe cache state and actual frame destinations before diagnosing missing ARP.

1. The latest lease time alone
2. The DNS response's display order alone
3. The remote application's listener number
4. The route and local next hop to use

Correct answer: D. The route and local next hop to use

Routing determines whether to resolve the destination directly or a local router. The ARP target is the chosen local next hop.

1. The conflicting numeric address claims remain
2. A DNS edit revokes all manually configured addresses
3. ARP maps only names, so a rename changes the numeric ownership
4. Renaming always changes the interface MAC

Correct answer: A. The conflicting numeric address claims remain

The address conflict exists at numeric address ownership and neighbor delivery. Naming changes alone do not remove the duplicate assignment.

1. The reverse zone's delegation
2. Every application's listener port
3. The TCP sequence state on every remote server
4. Peers' cached neighbor mappings

Correct answer: D. Peers' cached neighbor mappings

Peers may retain the old IP-to-MAC association. Verify approved cache update behavior and actual traffic rather than changing unrelated services.

1. Yes, as a TCP stream
2. No; ARP is carried directly using its own Ethernet protocol type
3. Yes, as an IPv4 UDP payload
4. Yes, as an IPv4 ICMP payload

Correct answer: B. No; ARP is carried directly using its own Ethernet protocol type

ARP has its own link-layer encapsulation on Ethernet. It helps prepare IPv4 delivery but is not an IPv4 application payload.

1. The appropriate VLAN's switch MAC table and physical topology
2. The authoritative PTR record alone
3. The address range in the DHCP console alone
4. The host's neighbor table alone without switch context

Correct answer: A. The appropriate VLAN's switch MAC table and physical topology

Follow the MAC through relevant switch ports and topology. An uplink entry may lead to another switch rather than the endpoint itself.

1. Forwarding and broadcast context depend on the VLAN
2. VLAN ID replaces the hardware address in all frames
3. Cross-VLAN entries prove one unstable same-context entry
4. All VLANs automatically share neighbor broadcasts

Correct answer: A. Forwarding and broadcast context depend on the VLAN

The same hardware address can appear in separate forwarding contexts. Investigate the affected broadcast domain rather than collapse all VLANs together.

1. Yes, FCS verifies address ownership
2. Yes, each reply carries a verified user signature
3. No; a received claim needs appropriate trust and corroboration
4. Yes, only the DHCP server can reply

Correct answer: C. No; a received claim needs appropriate trust and corroboration

Frame integrity is not ownership authentication. Correlate claims with authorized configuration and suitable network controls.

1. The sender resolves the neighbor again
2. The endpoint's address necessarily became invalid
3. The host must immediately obtain a different lease
4. The switch must block its port permanently

Correct answer: A. The sender resolves the neighbor again

Cache expiration does not prove endpoint removal. A later transmission can refresh the mapping through resolution.

1. They are always the same identifier fault
2. The first concerns IP ownership; the second concerns link-layer identity and learning
3. A duplicate IP requires a duplicate MAC too
4. A duplicate MAC requires a duplicate IP too

Correct answer: B. The first concerns IP ownership; the second concerns link-layer identity and learning

Different identifiers create different failure patterns. Both can affect delivery, so inspect actual advertised IP bindings and learned MAC locations.

1. Preserve the observed address, interface and time, then identify the competing owner
2. Clear every neighbor and switch entry before recording claims
3. Assign any apparently unused address without checking ownership
4. Disable conflict reporting while retaining configuration

Correct answer: A. Preserve the observed address, interface and time, then identify the competing owner

Evidence preservation and attribution support a targeted correction. Random reassignment or broad clearing can hide the cause and disrupt other endpoints.

1. 10.20.8.1
2. 0.0.0.0
3. 10.20.8.255
4. 10.20.9.20

Correct answer: A. 10.20.8.1

The destination is outside 10.20.8.0/24. The selected default next hop is local gateway 10.20.8.1.

1. The resolver was the link-layer next hop
2. The effective route treats the second laptop as an on-link peer
3. The destination must be reached through the default router
4. The sender skipped local addressing requirements

Correct answer: B. The effective route treats the second laptop as an on-link peer

A local peer route permits direct neighbor resolution and frame delivery. The router is not required for every IP transmission.

1. It changes the remote endpoint's mask automatically
2. It always chooses the intended default router regardless of mask
3. It ARPs for the remote address instead of using the intended gateway
4. It treats all destinations as remote even with the wider mask

Correct answer: C. It ARPs for the remote address instead of using the intended gateway

The wider mask incorrectly treats the destination as on-link. Missing replies can be caused by that classification, not a failed remote application.

1. Conflicting claimants or an intentional supported shared-address design
2. A guaranteed name-resolution timeout
3. A rule that every ordinary unicast address needs two owners
4. A guaranteed physical link break

Correct answer: A. Conflicting claimants or an intentional supported shared-address design

Competing bindings need attribution. Check whether the address is deliberately managed by a supported redundancy mechanism before declaring an accidental duplicate.

1. Every application session survives every failure
2. The gateway's neighbor binding to that virtual MAC
3. Every client's lease timer resets automatically
4. All cluster session state is synchronized by the MAC

Correct answer: B. The gateway's neighbor binding to that virtual MAC

A virtual next-hop identity can avoid a changed client binding. It does not by itself guarantee session or service state continuity.

1. An unrelated successful DNS answer
2. Frames for off-subnet traffic still target MAC A
3. Only the gateway's new inventory label
4. An unchanged lease time

Correct answer: B. Frames for off-subnet traffic still target MAC A

The actual Ethernet destination shows whether the old association is used. Verify a supported update and repeat the task.

1. The endpoint must be directly cabled to that uplink
2. No; follow the uplink through the topology to its downstream attachment
3. The table gives no forwarding-location information
4. The uplink management IP identifies the endpoint

Correct answer: B. No; follow the uplink through the topology to its downstream attachment

A learned port shows the forwarding direction from that switch. On an uplink it can represent many downstream devices.

1. The switch repeatedly learns that MAC on different ports
2. DNS necessarily increments its serial for each move
3. The MAC location must remain fixed despite both sources
4. Each clone automatically receives a unique MAC

Correct answer: A. The switch repeatedly learns that MAC on different ports

Source learning can move the same MAC entry as frames arrive from different attachments. Distinguish cloning from other causes of MAC movement.

1. Separate VLAN entries force shared broadcasts
2. Matching MAC strings prove one shared forwarding entry
3. The forwarding contexts differ and may legitimately reuse the identity
4. The entries prove duplicate IPv4 ownership

Correct answer: C. The forwarding contexts differ and may legitimately reuse the identity

Investigate within the actual affected VLAN and topology. Cross-context observations alone do not establish a single unstable forwarding entry.

1. A configured proxy behavior may answer on behalf of the remote destination
2. The remote NIC must be physically on this link
3. ARP broadcasts crossed all routers unchanged
4. The DNS resolver necessarily owns the target IP

Correct answer: A. A configured proxy behavior may answer on behalf of the remote destination

Proxy ARP can make a router answer a local resolution request for another destination. Verify the supported configuration and forwarding path.

1. The host's already-correct neighbor association
2. The switch's MAC forwarding table
3. The DHCP option list
4. The recursive cache

Correct answer: B. The switch's MAC forwarding table

Correct IP-to-MAC resolution does not ensure the switch sends frames to the intended attachment. Compare the two mappings separately.

1. Only that a DNS record expired
2. That the competing owner or overlapping assignment was removed
3. Only that the server console reloaded
4. Only that the reporting client rebooted

Correct answer: B. That the competing owner or overlapping assignment was removed

A quarantine or decline record reflects suspected occupancy. Releasing it without resolving ownership can repeat the conflict.

1. Only the users' roles with no attachment evidence
2. Only the gateway's public name
3. The affected port's VLAN, isolation, filtering and request/reply path
4. Only the required website's application version

Correct answer: C. The affected port's VLAN, isolation, filtering and request/reply path

The successful peer shows some gateway availability in that context. Local attachment and path differences are useful discriminators.

1. Every announcement must override all pinned entries
2. Only the DHCP search suffix
3. The gateway's unchanged IP proves the static MAC still matches
4. Its explicit neighbor policy and whether the static entry should change

Correct answer: D. Its explicit neighbor policy and whether the static entry should change

Static neighbor state may not follow dynamic updates. Use the intended management procedure rather than promise automatic replacement.

1. The earlier alert was necessarily false
2. The visible MAC has permanent authenticated ownership
3. No second claimant ever existed
4. One claimant is visible during the capture; an earlier second claimant is not ruled out

Correct answer: D. One claimant is visible during the capture; an earlier second claimant is not ruled out

Observation timing limits the inference. Correlate earlier logs, endpoint configuration and switch history to investigate the reported event.

1. Differences can be important evidence and should not be silently treated as identical
2. The outer source always proves the advertised IP is authorized
3. The sender field identifies an authenticated human
4. The two fields are interchangeable and need only one record

Correct answer: A. Differences can be important evidence and should not be silently treated as identical

The outer frame source and advertised sender identity serve different roles. Preserve discrepancies for analysis of actual packet construction and trust.

1. Peers need the correct new IP-to-MAC binding when they use the new address
2. All peers' bindings update without any evidence
3. Every switch must learn a new hardware address
4. The same MAC guarantees the old IP remains usable

Correct answer: A. Peers need the correct new IP-to-MAC binding when they use the new address

IP and MAC identity can change independently. Switch learning may remain stable while the usable neighbor address changes.

1. Only the DHCP duration
2. Only the printer hostname
3. Timestamped claimant traffic and switchport/configuration attribution for each MAC
4. Only which MAC was most recently printed

Correct answer: C. Timestamped claimant traffic and switchport/configuration attribution for each MAC

Mapping changes are a lead. Tie each claim to an actual endpoint and attachment before choosing which configuration to correct.

1. The DNS zone must have caused the conflict
2. The first successful packet proves unique ownership
3. The cache clear proves permanent resolution
4. An underlying ownership or path problem may be repopulating the bad state

Correct answer: D. An underlying ownership or path problem may be repopulating the bad state

Temporary recovery after clearing state is diagnostic evidence, not completion. Capture what recreates the mapping or misdelivery.

1. The reverse DNS zone first
2. The remote Internet route first
3. The remote application's role list first
4. The local broadcast forwarding and effective VLAN path

Correct answer: D. The local broadcast forwarding and effective VLAN path

Before expecting a reply, demonstrate request delivery on the local segment. Check switching context and relevant controls.

1. A reply proves complete application success
2. An ARP response is an authoritative DNS answer
3. ARP renewal extends the DHCP lease
4. Neighbor resolution has evidence of success; check subsequent IP, transport and application stages

Correct answer: D. Neighbor resolution has evidence of success; check subsequent IP, transport and application stages

Resolution is a prerequisite rather than an end-to-end acceptance test. Follow the actual task's next stage.

1. Separate static and dynamic ownership in the approved address plan and verify both endpoints
2. Configure both devices with the same static address
3. Disable all ARP replies
4. Raise the neighbor cache lifetime without correcting ownership

Correct answer: A. Separate static and dynamic ownership in the approved address plan and verify both endpoints

Overlapping assignment sources require a coordinated address-plan repair. Confirm the intended owners and that the conflict no longer recurs.

1. Only a matching reverse name
2. Only the displayed row's changed text
3. Only the current lease duration
4. Verify frames use the new mapping and the intended remote task works

Correct answer: D. Verify frames use the new mapping and the intended remote task works

Effective transmission and service outcome validate that the new association is used correctly. A displayed entry alone is narrower evidence.

1. The remote site is necessarily down
2. The gateway is the local neighbor; the remote website is reached through it
3. The resolver necessarily refused the lookup
4. The endpoint cannot send IP packets

Correct answer: B. The gateway is the local neighbor; the remote website is reached through it

Hosts normally resolve local next hops rather than every remote destination's MAC. This is expected routed forwarding behavior.

1. Any two timestamps can be joined without checking movement
2. They may describe different attachment and ownership states
3. All learned entries are permanent
4. A MAC match always establishes the same incident state

Correct answer: B. They may describe different attachment and ownership states

Correlate time as well as VLAN and identity. A correct historical table may not describe the later packet path.

1. No target because an address requires a hostname
2. The default gateway regardless of the installed specific route
3. The subnet broadcast because the target is remote
4. 198.51.100.20 because the selected route declares it on-link

Correct answer: D. 198.51.100.20 because the selected route declares it on-link

The selected route overrides a simple address-mask shortcut. Diagnose the effective route and whether its on-link declaration is appropriate for the actual attachment.

1. The intended active ownership and virtual-address behavior at that time
2. The vendor prefix alone
3. The last packet observed regardless of approved active state
4. The smaller numeric MAC

Correct answer: A. The intended active ownership and virtual-address behavior at that time

Compare actual claims with the approved redundancy configuration and transition timeline. A familiar vendor prefix or latest packet does not authenticate ownership.

1. A harmless static ARP entry without topology evidence
2. A switching loop or duplicated forwarding path
3. A cloned endpoint as the only possible cause
4. Normal mobility regardless of repeated frame copies

Correct answer: B. A switching loop or duplicated forwarding path

MAC movement can have several causes. Repeated frame copies and topology evidence can support a loop hypothesis rather than isolated cloned ownership.

1. New source learning and destination forwarding on the new attachment
2. Only the endpoint's inventory label
3. Only a passing gateway ping from an unrelated port
4. Only an unchanged IP-to-MAC row

Correct answer: A. New source learning and destination forwarding on the new attachment

The stale state is the MAC location, not necessarily the IP-to-MAC mapping. Observe forwarding recovery at the relevant switch.

1. Every address the proxy answers is reachable
2. The actual remote target directly answered on this link
3. The proxy answered locally, not that the remote target is reachable
4. The proxy verified the remote application's listener

Correct answer: C. The proxy answered locally, not that the remote target is reachable

Proxy resolution and downstream delivery are separate. Trace the router's forwarding and the remote response before claiming end-to-end reachability.

1. Permanent exclusive ownership of the address
2. Proof that DHCP and all static inventories agree
3. No conflicting response was observed under those conditions, not guaranteed permanent ownership
4. Proof that disconnected endpoints cannot claim it later

Correct answer: C. No conflicting response was observed under those conditions, not guaranteed permanent ownership

A quiet probe has a time and visibility scope. Address planning and server state remain necessary, especially for sleeping or disconnected endpoints.

1. Continue defending faster within the interval
2. Treat the second claim as a new lease allocation
3. Keep the address and suppress all error reporting
4. Stop using the address rather than repeatedly defend within that interval

Correct answer: D. Stop using the address rather than repeatedly defend within that interval

Repeated conflict within the defend interval requires relinquishing the address under that procedure. Avoid an endless competing-claim loop.

1. Guaranteed current ownership from a cross-VLAN match
2. A claimant location chosen from the first MAC match
3. A proof that the segments share a broadcast domain
4. Attributing a claimant to a port in the wrong forwarding context

Correct answer: D. Attributing a claimant to a port in the wrong forwarding context

Use VLAN and time with MAC and IP identity. An otherwise exact MAC match can refer to an unrelated isolated context.

1. An unintended intermediary can still pass traffic while misdirecting or observing the path
2. The expected IP address alone proves the MAC is authorized
3. A passing web task proves the intended local gateway binding
4. Successful forwarding authenticates the intermediary

Correct answer: A. An unintended intermediary can still pass traffic while misdirecting or observing the path

Service success is not ownership or path-integrity proof. Investigate the actual advertised binding and approved gateway identity.

1. Replies must use the same valid mapping as the request sender
2. Correct client neighbor state guarantees the server's return entry
3. A stale return entry prevents requests from reaching the server
4. Requests arrive at S but replies use the wrong link-layer destination

Correct answer: D. Requests arrive at S but replies use the wrong link-layer destination

Neighbor state exists independently in each sender. A valid forward mapping does not prove return delivery.

1. Accept stable gateway IP as proof that pinned MAC entries match
2. Update the authorized pinned entries or intended stable identity design
3. Change every client's IPv4 address
4. Clear unrelated resolver caches

Correct answer: B. Update the authorized pinned entries or intended stable identity design

The affected cohort points to explicit neighbor state that does not follow the transition. Correct that dependency while preserving unrelated controls.

1. The higher limit assigns unique MACs automatically
2. Suppressing the violation proves forwarding is now unambiguous
3. It may conceal duplicate identity and misdelivery without fixing ownership
4. A limit change reconciles every advertised IP owner

Correct answer: C. It may conceal duplicate identity and misdelivery without fixing ownership

A higher limit is not an identity repair. Confirm the virtualization design and assign supported unique identities where required.

1. The lease row alone proves B cannot exist
2. The newest of the two artifacts always proves ownership
3. The live reply alone proves B is authorized
4. Neither entry alone; investigate actual identity matching, static use and time

Correct answer: D. Neither entry alone; investigate actual identity matching, static use and time

Server state records allocation intent; a live packet records a claim. Reconcile both with endpoint configuration and the applicable matching rules.

1. That the affected endpoint received and used that reply
2. The generation of the reply on the observed side
3. The observed reply's sender fields
4. The existence of the packet at the capture point

Correct answer: A. That the affected endpoint received and used that reply

Observation location limits delivery claims. Check the endpoint side and effective neighbor state before attributing later failure.

1. Only one local ping immediately after a cache clear
2. Only that the edited configuration saved
3. Only the absence of an alert for a moment
4. Verify unique ownership, updated service references, and both affected endpoints' required tasks over time

Correct answer: D. Verify unique ownership, updated service references, and both affected endpoints' required tasks over time

Address repair can leave stale references and cached state. Validate both former claimants and the services that depend on the changed address.

1. Only the hostname's current A record
2. All effective interface addresses and advertised bindings, including secondary addresses
3. Only the MAC's vendor prefix
4. Only the primary address in inventory

Correct answer: B. All effective interface addresses and advertised bindings, including secondary addresses

A single interface can claim multiple protocol addresses. Inventory the complete effective configuration rather than just the documented primary.

1. A correct MAC makes VLAN context irrelevant
2. The tag changes the IP destination automatically
3. Neighbor success guarantees every downstream link context
4. Correct neighbor identity is insufficient when link context is wrong

Correct answer: D. Correct neighbor identity is insufficient when link context is wrong

Frame delivery depends on link context as well as destination identity. Verify the actual VLAN and forwarding path for the resolved next hop.

1. The entry prevents all independent static address conflicts
2. Other hosts, address ownership and forwarding paths still require appropriate controls
3. The local entry is automatically replicated across the segment
4. A static entry on one client authenticates every peer

Correct answer: B. Other hosts, address ownership and forwarding paths still require appropriate controls

A local pinned mapping has limited scope. Evaluate other endpoints and approved enforcement rather than treating one cache setting as segment-wide protection.

1. Remove or correct the unauthorized duplicate ownership and verify stable bindings
2. Schedule continuous clears as the permanent correction
3. Accept brief recovery without ownership verification
4. Raise cache lifetime while retaining both claimants

Correct answer: A. Remove or correct the unauthorized duplicate ownership and verify stable bindings

The cache follows recurring claims. Correct the source of conflicting ownership instead of repeatedly discarding its symptoms.

1. Replace the intended gateway before correcting the target
2. The client's effective route or gateway configuration
3. Treat the missing reply as proof that all gateways are down
4. Change the remote application listener first

Correct answer: B. The client's effective route or gateway configuration

Neighbor resolution follows the selected next hop. A missing response for an unintended target does not show the intended gateway is broken.

1. The expected IP label authenticates all claims
2. The collector's documented loss and incomplete observation coverage
3. A capture with drops still has complete event coverage
4. The one retained claimant proves exclusive ownership

Correct answer: B. The collector's documented loss and incomplete observation coverage

Missing observations can hide a second claimant. Use complementary endpoint, switch and configuration evidence to assess ownership.

1. Only inspect the unchanged virtual IP
2. Treat an announcement as proof of session continuity
3. Forwarding, policy and relevant session state beyond neighbor continuity
4. Only repeat the successful virtual-MAC check

Correct answer: C. Forwarding, policy and relevant session state beyond neighbor continuity

Stable neighbor identity addresses one dependency. It does not prove that connection state and the complete service path survive.

1. Treat migration as proof that no forwarding check is needed
2. Compare movement duration and task impact with the supported migration behavior before declaring a fault
3. Assume all approved moves are instantaneous and impact-free
4. Declare every observed MAC move a malicious duplicate

Correct answer: B. Compare movement duration and task impact with the supported migration behavior before declaring a fault

Context distinguishes expected mobility from persistent instability. Verify eventual stable learning and required service recovery.

1. The selected route, outgoing interface and that interface's neighbor binding
2. Combine both interface bindings into one permanent global entry
3. Use the first printed row regardless of route
4. Choose the binding from the interface with the newest DHCP lease

Correct answer: A. The selected route, outgoing interface and that interface's neighbor binding

Neighbor state is interface-scoped. Overlapping numeric addresses across attachments require route and interface context to interpret actual transmission.

1. Only a list of cache-clearing commands
2. Only a closed status label
3. Only the final address of one endpoint
4. Original conflicting claims, identified owners, approved correction, and timestamped stable task/ownership verification

Correct answer: D. Original conflicting claims, identified owners, approved correction, and timestamped stable task/ownership verification

A useful closure connects evidence to the correction and demonstrates its result. This makes recurrence and later review diagnosable.