Networking
23 free questions with worked answers, and 635 more in the full bank.
Free questions
What device is commonly used to connect multiple computers within a LAN?
1 mark · Easy
Which cable type is most commonly used for Ethernet connections?
1 mark · Easy
What is the purpose of DNS?
1 mark · Easy
Which of the following tools is used to diagnose network connectivity issues?
1 mark · Easy
What does VPN stand for?
1 mark · Easy
What is the primary function of a router?
4 marks · Hard
What protocol is used to send email?
4 marks · Hard
A user reports that they are unable to access the hospital management system due to a firewall blocking the connection. What should you do to resolve this issue?
4 marks · Hard
A junior admin is looking at a packet capture and notices MAC addresses are being used to forward frames. Which OSI layer is responsible for this activity?
1 mark · Easy
While investigating a slow application, you observe TCP window size zero messages in Wireshark. At what layer of the OSI model does this flow control issue reside?
3 marks · Medium
Users report that their web browsers are failing to negotiate TLS encryption with a newly deployed internal server. Which OSI layer is failing to establish this secure connection?
4 marks · Hard
An engineer connects a spectrum analyzer to a coax cable to check for electromagnetic interference. What OSI layer is being analyzed?
1 mark · Easy
A routing loop has caused TTL values to expire, dropping IP packets. In which OSI layer does the TTL field exist?
3 marks · Medium
During a network outage, a technician finds that a fiber optic cable was accidentally severed. Which layer of the OSI model is directly impacted by this physical break?
1 mark · Easy
An application requires persistent connections and checkpointing during a large file transfer so it can resume if interrupted. Which OSI layer provides these dialog control features?
4 marks · Hard
You are troubleshooting an IPsec VPN tunnel where ESP packets are being dropped by an intermediary firewall. Which OSI layer protocols are being blocked?
3 marks · Medium
A user complains that they cannot access a specific internal webpage, receiving an HTTP 500 error. At what OSI layer is this error generated?
1 mark · Easy
A switch receives a frame with a destination MAC address of FF:FF:FF:FF:FF:FF. Which OSI layer is responsible for flooding this frame out all ports?
3 marks · Medium
A small office connects all their computers to a single central switch. What physical topology is in use?
1 mark · Easy
An enterprise connects its 5 branch offices directly to every other branch office using point-to-point links for maximum redundancy. What topology does this represent?
3 marks · Medium
A legacy industrial control system uses a single coaxial cable that loops through each machine on the factory floor. If a break occurs, the entire segment fails. What topology is described?
4 marks · Hard
A campus network consists of several star-topology building networks connected together via a high-speed fiber backbone ring. Which term best describes this overall design?
1 mark · Easy
To save costs, a regional ISP connects its routers in a circle, where each router only links to its two nearest neighbors. What topology is deployed?
3 marks · Medium
More Networking questions (page 9 of 11)
Answers and explanations are in the full bank.
- A security analyst reports possible DNS cache poisoning against an internal resolver. Which change most effectively reduces the impact of a successful poisoning attempt? · 4 marks
- Internal clients send queries directly to root and TLD servers instead of the internal resolver. Which design corrects this and reduces unnecessary external traffic? · 3 marks
- Which record type is used to delegate a subdomain, such as a department, to its own authoritative name servers? · 3 marks
- Which DNS record type must be updated when a mail server hostname changes, so that mail is still delivered to the correct host? · 1 mark
- An internal server must resolve to one address for internal users and a different address for external users. Which DNS configuration delivers this? · 3 marks
- An IPv6 host has no ARP cache because IPv6 does not use ARP. Which mechanism resolves IPv6 link-layer addresses instead? · 3 marks
- NIDA must carry IPv6 traffic across an ISP segment that only supports IPv4. Which transition mechanism encapsulates IPv6 packets inside IPv4 for this purpose? · 4 marks
- Which routing protocol carries IPv6 prefixes natively and forms adjacencies over IPv6 link-local addresses? · 3 marks
- An IPv6 packet is too large for the path MTU and routers refuse to fragment it. What must happen for delivery to succeed? · 4 marks
- Which IPv6 statement correctly contrasts link-local and unique local addresses? · 3 marks
- Four parallel links between two switches are bundled into one logical port. Which negotiation keeps the bundle forwarding if one physical link fails? · 3 marks
- A device is offline and its monitoring shows a trap sent just before the failure. What does this indicate about the monitoring approach? · 3 marks
- Which statement about inter-VLAN routing is correct? · 3 marks
- Which statement about policy routing is correct? · 4 marks
- Which statement about beamforming is correct? · 4 marks
- Which statement about MFA is correct? · 4 marks
- During a workshop assessment, the reported condition is: A switch port shows down/down and no link LEDs after a workstation is connected. What should be checked first? · 1 mark
- During a workshop assessment, the reported condition is: An Ethernet interface reports steadily increasing CRC errors while link remains up. Which cause should be investigated? · 3 marks
- During a workshop assessment, the reported condition is: One end of an Ethernet link is forced to full duplex while the other end operates at half duplex. What symptom is likely? · 1 mark
- During a workshop assessment, the reported condition is: Users can ping a server by IP address but cannot reach it by hostname. Which service should be checked next? · 3 marks
- During a workshop assessment, the reported condition is: A DHCP client broadcasts requests but receives no lease after a router was inserted between it and the server. What configuration is likely missing? · 1 mark
- During a workshop assessment, the reported condition is: A Windows host assigns itself a 169.254.x.x address. What does this usually indicate? · 3 marks
- During a workshop assessment, the reported condition is: A host can reach devices in its own subnet but no remote networks, while peer hosts work normally. Which local setting is the best first suspect? · 1 mark
- During a workshop assessment, the reported condition is: Two access ports intended for the same department were accidentally assigned to different VLANs. What is the expected effect? · 3 marks
- During a workshop assessment, the reported condition is: A trunk's native VLAN differs between the two connected switches. What risk does this create? · 1 mark
- During a workshop assessment, the reported condition is: A redundant Layer 2 link is in a spanning-tree blocking or discarding state. How should this normally be interpreted? · 3 marks
- During a workshop assessment, the reported condition is: Two ports configured for an LACP bundle remain individual and suspended. What should be compared? · 1 mark
- During a workshop assessment, the reported condition is: Several nearby access points use the same channel and clients experience high airtime utilization. Which improvement is appropriate? · 3 marks
- During a workshop assessment, the reported condition is: A wireless client shows strong signal strength but a very low signal-to-noise ratio. What does this mean? · 1 mark
- During a workshop assessment, the reported condition is: Users receive incorrect default gateways after an unauthorized device begins answering DHCP requests. Which control directly addresses this switch-layer threat? · 3 marks
- During a workshop assessment, the reported condition is: Interactive applications are slow, but throughput tests are acceptable and ping shows long round-trip times. Which metric best matches the symptom? · 1 mark
- During a workshop assessment, the reported condition is: A voice call has missing audio fragments while average delay remains acceptable. Which network condition is the likely cause? · 3 marks
- During a workshop assessment, the reported condition is: A router knows 10.0.0.0/8 and 10.20.0.0/16, and the destination is 10.20.5.8. Which route is preferred for forwarding? · 1 mark
- During a workshop assessment, the reported condition is: Inside hosts have private addresses and translations appear in the NAT table, but return traffic is routed to the wrong public interface. What must be corrected? · 3 marks
- During a workshop assessment, the reported condition is: A firewall or ACL has a broad deny rule above a required specific permit. What will happen in a top-down first-match policy? · 1 mark
- During a workshop assessment, the reported condition is: Logs from different network devices show inconsistent timestamps during an outage investigation. Which service should be corrected? · 3 marks
- Why is IPsec commonly recommended for protecting IPv6 traffic even though IPv6 has built in IPsec support? · 3 marks
- A dual stack host is expected to reach a service that publishes only an AAAA record. Which condition must hold for the connection to succeed? · 1 mark
- What is the role of an IPv6 router advertisement from the network administrator perspective? · 3 marks
- NIDA assigns addresses from the shared address space used by some ISPs so multiple subscribers receive the same public address. Which mechanism and range are involved? · 3 marks
- An IPv6 host is assigned a prefix from a router advertisement but must keep a temporary address for privacy. Which mechanism generates those temporary addresses? · 4 marks
- An IPv6 host needs to determine its own address without a DHCP server. Which mechanism performs this function? · 3 marks
- Which IPv6 address type is used to send a message to every device on the local link? · 1 mark
- Users can browse websites by IP address but not by name after a DNS server migration. Which change most directly identifies the fault? · 3 marks
- A DHCP scope is exhausted and new clients receive an APIPA address starting with 169.254. What does this tell the administrator? · 1 mark
- Which two protocols are used by IP telephony, and what does each carry? · 1 mark
- NIDA must connect its phone system to another institution over an IP connection. Which technology provides this interconnection to a provider? · 3 marks
- A caller hears clipping and robotic speech but the call connects successfully. Which cause best explains this pattern on a congested link? · 4 marks
- NIDA requires that when a receptionist is unavailable the phone rings a group of staff in turn. Which feature implements this? · 3 marks
- Which design ensures an emergency call from a phone reaches the correct geographic location even when the call is placed from an internal extension? · 3 marks
- Two distribution switches are linked by redundant cabling and the network has no spanning tree configured. Which device will be elected root bridge by default? · 1 mark
- A switch port that should only ever connect an end host keeps sending and receiving BPDUs, which an attacker could use to influence the spanning tree topology. Which feature shuts that port down when BPDUs are detected? · 3 marks
- Finance and Human Resources must be on separate IP subnets while sharing the same physical switch. What must be configured so hosts in the two VLANs can reach each other? · 1 mark
- Voice traffic from IP phones must be carried alongside data across a trunk link. Which 802.1Q mechanism separates the voice VLAN from the data VLAN on the same wire? · 3 marks
- An OSPF router must form adjacencies with routers on a Frame Relay or MPLS WAN where broadcast and multicast are unavailable. Which OSPF network type must be configured on those interfaces? · 4 marks
- Which OSPF LSA type is generated by an area border router to advertise networks it has learned from other areas? · 3 marks
- A router has three routes to the same destination network: one learned via EIGRP, one via OSPF, and one configured as a static route. Which route is installed in the routing table? · 1 mark
- A router holds 10.0.0.0/8 learned by protocol and also has 10.1.1.0/24 configured as a directly connected network. Which route is used for a packet destined to 10.1.1.5? · 3 marks
- An access port in a staff office should not connect more than one end host. Which control enforces that, and what is the default violation action? · 1 mark
- Under TIA-568 standards, what is the maximum permanent-link distance between a telecommunications outlet and the work area, and why does it matter for a cabling layout drawing? · 3 marks