CCNA (200-301) – Comprehensive Review Flashcards

Question-and-Answer style flashcards summarizing key CCNA (200-301) concepts from Modules 1–9, covering networking fundamentals, switching, routing, wireless, security, QoS, SDN, and automation.

What address field does a router examine to choose the correct egress interface for a packet?

The destination IP address.

Why will a switch flood a frame out all ports except the one it came in on?

Because the destination MAC address has not yet been learned.

What is the primary function of an Intrusion Prevention System (IPS) sensor?

To analyze network traffic and block potential threats.

What characterizes an ad-hoc wireless LAN?

Direct communication occurs between wireless clients without an access point.

What is the key distinction between client-server and peer-to-peer architectures?

Client-server uses a centralized server for resources; peer-to-peer clients share resources among themselves.

What design tasks can you perform with Cisco Catalyst Center?

Create a topology, allocate IP addresses, and place devices on a floor plan.

Which hypervisor runs directly on the server hardware with no host OS?

Type 1 (native or bare-metal) hypervisor.

What is the purpose of TCP’s three-way handshake?

To establish a reliable connection between two devices.

Why is a three-tier campus architecture scalable?

New buildings can be added simply by connecting their distribution layer to the core layer.

In a spine-leaf data-center, what role do Top-of-Rack (ToR) switches play?

They are leaf switches connecting servers to the spines.

Which WAN option offers dedicated bandwidth and predictable latency with low bandwidth needs?

A point-to-point PPP connection.

What single device best suits a SOHO with both wired and wireless clients?

A wireless router with built-in Ethernet ports connected to a cable/DSL modem.

Which cloud deployment blends public-cloud flexibility with on-premises security?

Hybrid cloud.

Which coax type is preferred for TVs and cable modems?

RG-6 coaxial cable.

Which twisted-pair cable is best against high EMI?

Shielded Twisted Pair (STP).

Cheapest twisted-pair category fully supporting 1 Gbps to 100 m?

Category 5e.

Which cable connects two PCs directly?

An Ethernet crossover cable.

Which fiber type minimizes modal dispersion over long distances?

Single-mode fiber (SMF).

Which fiber connector maximizes port density on a panel?

MTRJ connector.

Which fiber standard supports 1 Gbps up to ~200 m on MMF and is low-cost?

1000BASE-SX.

What technology powers APs or IP cameras through the Ethernet cable?

Power over Ethernet (PoE).

A rising I/O error counter often indicates what physical-layer mismatch?

Duplex mismatch.

How many bits are in an IPv4 address and how are they shown?

32 bits displayed in dotted-decimal notation.

Which IPv4 range is private: 192.0.2.0/24, 172.16.0.0/12, 203.0.113.0/24, or 8.8.8.0/24?

172.16.0.0 – 172.31.255.255.

Which NAT variant lets many inside hosts share one public IP via ports?

PAT (Port Address Translation).

Which IP flow type is ideal for a CEO video stream to many interested PCs?

Multicast.

Which IPv4 parameter is NOT manually configured (IP, mask, gateway, MAC)?

MAC address – it’s burned into the NIC.

Correct DHCP message sequence acronym?

DORA – Discover → Offer → Request → Acknowledgement.

Which DNS record creates an alias to another FQDN?

CNAME record.

Smallest /30 subnet mask usable between two routers?

255.255.255.252 (/30).

How many host bits must you borrow to create at least five subnets?

Borrow 3 bits (2³ = 8 subnets).

Usable hosts per /27 subnet?

30 usable addresses.

First usable IP in the second /29 of 192.168.10.0/24?

192.168.10.9.

192.168.1.130 /26 belongs to which subnet?

192.168.1.128/26.

Decimal 157 equals what hex value?

0x9D.

How many hexadecimal digits represent an IPv6 address?

32 hex digits (128 bits).

How do you compress consecutive all-zero quartets in IPv6?

Replace the run with a double colon (::).

IPv6 traffic type ‘Anycast’ is best described as?

One-to-nearest (one sender, delivered to the closest of many receivers).

Which IPv6 address is global unicast? FE80::1, FF02::1, 2001:DB8::1, ::1

2001:DB8::1.

What address reaches all IPv6 nodes on the link?

FF02::1.

IPv6 link-local addresses begin with which prefix?

FE80::/10.

Unique-local IPv6 addresses start with what bits?

FC00::/7 (commonly FDxx::/8).

IPv6 loopback address?

::1/128.

IPv6 unspecified address?

::/128 (all zeros).

Which IPv6 mechanism replaces ARP?

The solicited-node multicast with Neighbor Discovery (ND).

First step in EUI-64 interface-ID creation?

Split the MAC and insert FFFE in the middle.

What does SLAAC do?

Allows a host to self-generate an IPv6 address using router advertisements plus EUI-64.

Which switch type can forward at both Layer 2 and Layer 3?

A multilayer switch.

Identical first 6 hex digits in MAC addresses indicate what?

Same manufacturer OUI.

CLI command to disable CDP on a single interface?

no cdp enable (under interface config).

Vendor-neutral LLDP disables outbound advertisements with what command?

no lldp transmit (under interface).

Why create separate VLANs per department?

To place each on its own broadcast domain for security and performance.

Fast way to put Gi0/1-2 into VLAN 10?

interface range gi0/1-2; switchport access vlan 10.

Router-on-a-stick requires what on the router interface?

Subinterfaces, each tagged for a VLAN.

Layer-3 switch inter-VLAN routing uses what?

Switch Virtual Interfaces (SVIs).

Command that converts a switchport into a Layer-3 routed port?

no switchport.

Which frames on an 802.1Q trunk are untagged?

Frames belonging to the native VLAN.

To form a trunk with a remote port in dynamic auto, set local mode to?

dynamic desirable.

Restrict trunk to VLANs 10,20,30 CLI?

switchport trunk allowed vlan 10,20,30.

Command to specify voice VLAN 400 on an access port?

switchport voice vlan 400.

Which STP field is NOT part of the bridge ID?

Port priority.

Default STP reconvergence time after link failure?

50 seconds (20 + 15 + 15).

PVST+ allows per-VLAN root bridges by doing what?

Assigning different bridge priorities per VLAN.

PortFast purpose?

Send an access-port directly to Forwarding to minimize host delay.

STP enhancement preventing a superior BPDU from another switch?

Root Guard.

Which feature moves a port to loop-inconsistent if BPDUs stop arriving?

Loop Guard.

Which enhancement blocks BPDU exchange on an AS boundary?

BPDU Filter.

Enable auto-shutdown of PortFast ports receiving BPDUs?

BPDU Guard.

STP variant minimizing instances yet optimizing VLAN paths?

MSTP (Multiple Spanning Tree Protocol).

Typical RSTP convergence time window?

A few milliseconds up to ~6 seconds.

Command to verify Rapid-PVST mode?

show spanning-tree summary.

Critical EtherChannel requirement for all member ports?

Identical speed and duplex settings.

PAgP mode combination that forms a channel: auto vs desirable?

Auto on one side, desirable on the other.

EtherChannel load-balance on src-dst MAC fits what traffic pattern?

Varied unicast flows with many source/destination pairs.

Command to actively create PAgP EtherChannel 1?

channel-group 1 mode desirable.

Layer-3 EtherChannel key step?

Assign an IP address to the port-channel interface.

Which address does a host ARP for when sending off-subnet traffic?

The MAC address of its default gateway.

Which route wins among many to same network?

The one with the lowest administrative distance.

EIGRP is classified as what kind of routing protocol?

Advanced distance-vector.

When would OSPF outrank EIGRP?

If EIGRP’s administrative distance is manually increased above 110.

Best method to give a remote router Internet via HQ?

Configure a static default route pointing to HQ.

Proper static route syntax to reach 192.168.50.0/24 via 192.168.10.254?

ip route 192.168.50.0 255.255.255.0 192.168.10.254.

Static host route for 10.10.10.10 via 10.10.10.2?

ip route 10.10.10.10 255.255.255.255 10.10.10.2.

Floating static route above OSPF’s AD110 should use what AD?

A value higher than 110, e.g., 120.

OSPF Hello multicast IPv4 address?

224.0.0.5.

Why elect a DR/BDR on multi-access networks?

To reduce the number of adjacencies.

Interface priority 0 effect in OSPF?

Prevents that interface from becoming DR/BDR.

How to shrink an oversized LSDB?

Divide the network into multiple OSPF areas.

Type 1 LSA advertises what?

All directly connected networks of a router within an area.

Command to stop OSPF Hellos on Gi0/1 only?

router ospf X; passive-interface gig0/1.

Routing table code ‘IA’ means what in OSPF?

Inter-Area route learned from another area.

Default HSRP hold time before standby becomes active?

10 seconds.

Which FHRP lets a physical interface share the virtual IP?

VRRP.

GLBP load-balancing methods include?

Round-robin, weighted, and host-dependent (all of the above).

Independent APs risk what drawback?

Higher chance of configuration errors and poor scalability.

Which AP mode performs only background monitoring?

Monitor mode.

Unique MAC that identifies a specific AP radio?

BSSID.

Which band is NOT used by WLANs: 2.4 GHz, 5 GHz, 6 GHz, 7 GHz?

7 GHz.

Common interference source in 2.4 GHz?

Bluetooth devices.

Which 802.11 standard first used 5 GHz 54 Mbps?

802.11a.