41. What is the primary purpose of VLANs?
- a) To logically segment networks without physical separation
- b) To increase network speed
- c) To replace routers
- d) To encrypt network traffic
Answer: A - VLANs (Virtual LANs) create isolated broadcast domains within a single switch infrastructure.
42. Which IPv6 address type is equivalent to IPv4's 127.0.0.1?
- a) ::1
- b) ::
- c) FE80::
- d) 2001::
Answer: A - ::1 is the IPv6 loopback address (equivalent to IPv4's 127.0.0.1).
43. What does OSPF stand for?
- a) Open Shortest Path First
- b) Optimal Shortest Path Forwarding
- c) Open System Packet Forwarding
- d) Operational System Path Finder
Answer: A - OSPF is a link-state routing protocol that uses Dijkstra's algorithm.
44. Which protocol is used for automatic IPv6 address configuration?
- a) SLAAC (Stateless Address Autoconfiguration)
- b) DHCPv6
- c) ARPv6
- d) ICMPv6
Answer: A - SLAAC allows devices to self-configure IPv6 addresses without a DHCP server.
45. What is the purpose of STP (Spanning Tree Protocol)?
- a) To prevent network loops in switched networks
- b) To encrypt VLAN traffic
- c) To assign IP addresses automatically
- d) To connect wireless networks
Answer: A - STP blocks redundant paths to prevent broadcast storms while maintaining fault tolerance.
46. Which port does HTTPS use by default?
- a) 443
- b) 80
- c) 8080
- d) 22
Answer: A - HTTPS (HTTP Secure) uses port 443 for encrypted web traffic.
47. What is the main advantage of IPv6 over IPv4?
- a) Larger address space (128-bit vs 32-bit)
- b) Built-in encryption
- c) No need for routers
- d) Faster packet processing
Answer: A - IPv6's 128-bit addressing provides 3.4×10³⁸ addresses vs IPv4's 4.3 billion.
48. Which routing protocol uses the Bellman-Ford algorithm?
- a) RIP
- b) OSPF
- c) BGP
- d) EIGRP
Answer: A - RIP (Routing Information Protocol) uses hop count with a max of 15.
49. What does QoS (Quality of Service) manage?
- a) Network traffic prioritization
- b) IP address allocation
- c) Wireless signal strength
- d) DNS resolution speed
Answer: A - QoS ensures critical traffic (e.g., VoIP) gets bandwidth priority.
50. Which protocol is used for voice/video communication?
- a) RTP
- b) FTP
- c) SNMP
- d) HTTP
Answer: A - RTP (Real-time Transport Protocol) delivers audio/video over IP networks.
51. What is a /64 prefix in IPv6 typically used for?
- a) A single subnet
- b) An entire organization
- c) A global routing prefix
- d) A loopback address
Answer: A - The first 64 bits are for routing, the last 64 for interface IDs (EUI-64).
52. Which device operates at Layer 7 of the OSI model?
- a) Application firewall
- b) Switch
- c) Router
- d) Hub
Answer: A - Layer 7 devices can filter traffic based on application data (e.g., HTTP headers).
53. What is the purpose of BGP (Border Gateway Protocol)?
- a) To exchange routing information between autonomous systems
- b) To assign local IP addresses
- c) To encrypt internet traffic
- d) To manage VLAN configurations
Answer: A - BGP is the protocol that makes the internet work by connecting ISPs.
54. Which IPv6 address type is used for multicast?
- a) FF00::/8
- b) FE80::/10
- c) 2000::/3
- d) ::1/128
Answer: A - IPv6 multicast addresses always start with FF (FF00::/8).
55. What does MPLS stand for?
- a) Multiprotocol Label Switching
- b) Multi-Path Link State
- c) Managed Packet Label System
- d) Multiplexed Protocol Layer Security
Answer: A - MPLS uses labels (not IP addresses) for faster packet forwarding.
56. Which protocol is used for synchronizing time across networks?
- a) NTP
- b) SNTP
- c) FTP
- d) SMTP
Answer: A - NTP (Network Time Protocol) synchronizes clocks to within milliseconds.
57. What is the purpose of 802.1Q tagging?
- a) To identify VLAN membership on trunk links
- b) To encrypt wireless traffic
- c) To prioritize QoS traffic
- d) To authenticate network devices
Answer: A - 802.1Q inserts a 4-byte VLAN tag into Ethernet frames.
58. Which cloud service model provides virtual machines?
- a) IaaS (Infrastructure as a Service)
- b) PaaS (Platform as a Service)
- c) SaaS (Software as a Service)
- d) FaaS (Function as a Service)
Answer: A - IaaS provides raw compute/storage (e.g., AWS EC2, Azure VMs).
59. What does SDN stand for in networking?
- a) Software-Defined Networking
- b) Secure Data Network
- c) System Domain Name
- d) Switched Digital Network
Answer: A - SDN separates control plane (software) from data plane (hardware).
60. Which protocol is used for zero-configuration networking?
- a) mDNS (Multicast DNS)
- b) DHCP
- c) ARP
- d) ICMP
Answer: A - mDNS (used by Apple Bonjour) resolves hostnames without a DNS server.