200-301 CCNA practice questions: Network Access

Answer: C. Topic 2.6. Cisco documents FlexConnect as the capability of an access point to put wireless client traffic directly on the network at the access point (local switching) instead of centralizing it to the controller, and describes FlexConnect access points as able to switch client data traffic locally and perform client authentication locally when their connection to the controller is lost. That is exactly the branch survivability the requirement asks for. Monitor and sniffer are the non-client-serving modes, and local mode is the default centrally switched mode in which client traffic is carried in the CAPWAP tunnel to the controller. Source: Cisco 200-301 CCNA v1.1 Exam Topics - Section 2: Network Access

Answer: A. Topic 2.5.a and 2.5.b. Cisco defines the Rapid PVST+ roles as root (a forwarding port elected for the spanning-tree topology), designated (a forwarding port elected for every switched LAN segment), alternate (a blocked port providing an alternate path to the root bridge) and backup (a blocked port in a loopback configuration). The states map to behavior as follows: discarding or blocking forwards nothing and learns nothing, learning does not forward but does learn addresses, and forwarding does both. So Altn/BLK on Gi1/0/2 means a loop-free standby path toward the root that is ready to be unblocked if the root port fails. Source: Cisco 200-301 CCNA v1.1 Exam Topics - Section 2: Network Access

Answer: C. Topic 2.2.a. The show interfaces trunk output is read as three narrowing lists: what the administrator allowed, which of those VLANs are allowed and active (they exist locally and are not shut down), and which of those are in the spanning-tree forwarding state and not pruned. VLAN 20 drops out at the second list, so the fault is on SW1 itself: the VLAN has to be created in the VLAN database (vlan 20) or brought out of shutdown before the trunk can carry it. Allowing a VLAN on a trunk never creates it. By default a trunk allows VLANs 1 to 4094, so appearing in the first list proves nothing about the VLAN existing. Source: Cisco 200-301 CCNA v1.1 Exam Topics - Section 2: Network Access

Answer: C. Topic 2.5.c. The Catalyst optional spanning-tree features chapter gives the behaviour word for word: even if the interface receives a bridge protocol data unit, spanning tree does not place the port into the blocking state, and spanning tree sets the operating state of the port to non-PortFast even if the configured state remains PortFast edge, and starts participating in the topology change. The configuration line stays in place; what changes is the operational edge status. This is the point PortFast is most often misread on: the same chapter describes PortFast as bringing an access or trunk port straight from blocking to forwarding, bypassing the listening and learning states, and warns that enabling it on an interface connected to a switch or hub could prevent spanning tree from detecting and disabling loops. It is the separate features that change the outcome: BPDU guard puts such a port in the error-disabled state, and BPDU filtering keeps the port from sending or receiving BPDUs at all. Source: Cisco 200-301 CCNA v1.1 Exam Topics - Section 2: Network Access

Answer: A. Topic 2.6, split-MAC architecture. RFC 5416, the CAPWAP binding for IEEE 802.11, divides the 802.11 MAC between the access point (WTP) and the controller (AC) in section 2.2.1: all real-time IEEE 802.11 services, including the Beacon and Probe Response frames, are handled on the WTP, together with power management, packet buffering and queuing, while all remaining 802.11 MAC management frames are supported on the AC. Its function table places association, disassociation and reassociation, IEEE 802.1X/EAP, RSNA key management and the distribution and integration services on the AC. A client therefore gets its probe answer from the radio it hears, but its association and its authentication are decided centrally. Source: Cisco 200-301 CCNA v1.1 Exam Topics - Section 2: Network Access; split-MAC function table verified at RFC 5416 section 2.2.1 ('all real-time IEEE 802.11 services, including the Beacon and Probe Response frames, are handled on the WTP'), https://www.rfc-editor.org/rfc/rfc5416