Networking Fundamentals Flashcards

Which tunneling protocol encapsulates Layer 2 Ethernet frames over an IP network and is commonly used in data center fabrics?

Answer: VXLAN

VXLAN (Virtual Extensible LAN) encapsulates Layer 2 frames in UDP packets, enabling scalable overlay networks across Layer 3 boundaries.

A host is assigned the IP address 192.168.10.50/26. What is the broadcast address of its subnet?

Answer: 192.168.10.63

A /26 mask gives blocks of 64; the subnet containing .50 starts at .0 and ends at .63, making .63 the broadcast address.

What distinguishes a stateful firewall from a stateless packet filter?

Answer: Stateful firewalls track connection state and allow return traffic automatically

Stateful firewalls maintain a connection table to track session state, automatically permitting return traffic for established connections.

Which protocol provides redundant default gateway functionality by allowing multiple routers to share a virtual IP address?

Answer: HSRP/VRRP

HSRP (Cisco) and VRRP (open standard) are First Hop Redundancy Protocols that present a shared virtual IP as the default gateway for hosts.

What is the purpose of Link Aggregation Control Protocol (LACP) in a network?

Answer: Bundle multiple physical links into one logical high-bandwidth channel

LACP (802.3ad) negotiates and manages link aggregation groups (LAGs), combining multiple physical interfaces for increased bandwidth and redundancy.

Which DNS record type maps a hostname to an IPv6 address?

Answer: AAAA record

AAAA (quad-A) records store 128-bit IPv6 addresses, analogous to how A records store 32-bit IPv4 addresses.

When configuring a network interface in Aruba AOS-S, what is the effect of placing a port in 'access' mode with VLAN 20?

Answer: The port carries only untagged VLAN 20 traffic

An access port in VLAN 20 strips 802.1Q tags and forwards only untagged frames belonging to VLAN 20, typically used for end-host connections.