Cisco CCNA Practice Test (200-301)

Southbound APIs are used by the network controller to communicate with network devices such as switches and routers. They enable the controller to send instructions and configurations to these devices, managing the data plane. The other options are not functions of Southbound APIs: Northbound APIs allow applications to communicate with the controller; defining user access policies is related to security mechanisms; facilitating direct user interaction with infrastructure is not associated with Southbound APIs.

First hop redundancy protocols provide redundancy for the default gateway by allowing multiple routers to share a virtual IP address. This ensures that if one router fails, another can take over seamlessly, maintaining network connectivity for hosts. Dynamic routing protocols share routing information between routers but do not present a single virtual IP to hosts. Spanning Tree Protocols prevent loops in switched networks, and DHCP assigns IP addresses to hosts.

SNMP (Simple Network Management Protocol) is used to collect and modify information about network devices, allowing administrators to monitor network performance and configure devices remotely. NTP (Network Time Protocol) synchronizes time between devices. FTP (File Transfer Protocol) transfers files between hosts. Telnet provides remote command-line access but lacks the network management capabilities of SNMP.

In this data structure, a list is indicated by square brackets [ ] and contains multiple elements. The value associated with the "interfaces" key is a list because it is enclosed in square brackets and includes multiple objects representing the interfaces.

Terraform is specifically designed to provision and manage infrastructure across various cloud providers using a declarative configuration language. It allows for consistent and repeatable deployment of infrastructure as code. In contrast, Ansible, Chef, and Puppet are primarily configuration management tools that automate the setup and management of software on existing servers but are not specialized in provisioning infrastructure resources across multiple cloud platforms.

Cisco DNA Center provides centralized management and automation for both wired and wireless network devices in an enterprise environment. It enables policy-based provisioning, network assurance, and analytics across the entire network infrastructure. A Wireless LAN Controller manages wireless access points but is limited to wireless networks and does not manage wired devices. An Access Point provides wireless connectivity to clients but does not offer centralized management capabilities. A Layer 2 Switch operates at the data link layer and forwards frames within a local network segment but lacks centralized management and automation features.

Mandatory badge scanning at entrances is a form of physical access control, which manages who can physically enter secure areas. User awareness and training programs involve educating employees about security policies and threats, while network monitoring relates to observing network activity for security purposes.

In link-state routing protocols like Open Shortest Path First (OSPF), routers must be in the same area to form a neighbor adjacency. A mismatch in area IDs will prevent the routers from establishing a neighbor relationship. Process IDs are locally significant identifiers and do not need to match between routers. Interface descriptions are used for administrative purposes and do not affect routing protocol operations. Router priorities influence the selection of a designated router (DR) but do not prevent neighbor formation.

The banner motd command configures a "Message of the Day" banner, often used to display legal warnings or informational messages when users access the device.

Routers use the longest prefix match when selecting a route to forward a packet. This means the router looks for the most specific route that matches the destination IP address. If multiple routes are available, the one with the longest network prefix (most matching bits) is chosen. Administrative distance and routing protocol metrics are considered only if multiple routes have the same prefix length.

Secure Shell (SSH) should be used because it encrypts both authentication credentials and management data, providing secure remote access to network devices. Telnet transmits data in plaintext, making it insecure. HTTP is used for web interfaces but does not encrypt data by default. The console port provides direct local access and is not used for remote management over a network.

The 802.1Q standard provides VLAN tagging by inserting a tag into the Ethernet frame header, allowing multiple VLANs to be transported over a single link between switches. This tagging enables the receiving switch to identify which VLAN each frame belongs to. 802.3 defines Ethernet standards without VLAN tagging. 802.11 relates to wireless networking, and 802.1D defines the Spanning Tree Protocol for loop prevention.

Physical access control involves using mechanisms like locks, access cards, and security personnel to regulate who can enter specific physical locations. This ensures that only authorized individuals have access to sensitive areas. While user awareness training educates employees about security practices, network security measures protect digital resources, and data encryption policies safeguard data integrity, none of these options directly manage physical entry to facilities.

The most likely cause of the network slowdown is the use of an Ethernet shared media connection, such as a hub. In a shared media environment, all connected devices share the same bandwidth and collision domain. When multiple devices attempt to communicate simultaneously, data collisions occur, leading to retransmissions and degraded performance. Point-to-point connections using switches provide dedicated bandwidth and separate collision domains for each connection, which prevents collisions and maintains optimal performance. The issue is not related to broadcast storms, full-duplex communication, or incompatible cables in this scenario.

This command shows the status and configuration details for SSH, verifying if it is enabled and functioning.