Practice Test Flashcards

Which of the following statements concerning TCP and UDP are correct?

Answer: TCP is a secure protocol UDP is not secure.

Explanation: The main difference between these protocols is that TCP is a connection-oriented protocol, while UDP is a connectionless one. Each of the protocols has its strengths and weaknesses. One is much faster, while the other is safer.

Which of the wireless protocols is the most reliable?

Answer: WPA3

WPA3 is the latest and most secure wireless security protocol, offering significant improvements over its predecessors like WPA2, WPA, and WEP. It provides enhanced encryption, stronger authentication, and protection against brute-force attacks. These advancements make WPA3 the most reliable choice for securing modern wireless networks.

What are the two main types of site-to-site VPNs?

Answer: Extranet Based VPN

Site-to-site VPNs connect entire networks, rather than individual hosts, over a public network. Intranet-based VPNs connect different sites belonging to the *same* organization, allowing secure access to internal resources. Extranet-based VPNs connect different sites of *different* organizations, such as business partners or suppliers, enabling secure collaboration between them.

Which of the protocols listed below is a routed protocol?

Answer: IP

A routed protocol is responsible for carrying user data across an internetwork, providing addressing and encapsulation for data packets. IP (Internet Protocol) is the primary routed protocol, enabling end-to-end communication across diverse networks. Routing protocols like OSPF and RIP, on the other hand, are used by routers to *exchange* routing information about how to reach networks using routed protocols.

DSCP bits are____ bits.

Answer: 6

DSCP (Differentiated Services Code Point) is a field within the IP header used for Quality of Service (QoS) mechanisms. It consists of 6 bits, which allows for 64 different possible classifications (2^6 = 64) of network traffic. These classifications enable routers to prioritize different types of data, ensuring critical applications receive preferential treatment.

What command is used to turn on the Cisco router interface?

Answer: no shutdown

In Cisco IOS, network interfaces are often administratively shut down by default or can be manually disabled. The `no shutdown` command is used within the interface configuration mode to bring an interface up and enable it to send and receive traffic. This command is essential for activating a router's physical or logical connections.

During a Traffic Exceed, QoS.... is the mechanism used. Exceed Traffic is buffered and transmitted again after a brief delay.

Answer: Traffic Shaping

Traffic shaping is a Quality of Service (QoS) mechanism designed to manage and smooth out network traffic flow. When traffic exceeds a configured rate, traffic shaping buffers the excess packets and then transmits them at a regulated, consistent pace. This prevents bursts of data from overwhelming the network, reducing congestion and packet loss for critical applications.

True/False: On Ethernet technology, CSMA/CD mechanisms prevent transmission at the same time.

Answer: B) True

CSMA/CD (Carrier Sense Multiple Access with Collision Detection) is a media access control method used in half-duplex Ethernet networks. It ensures that devices listen for ongoing transmissions before sending data and detect collisions if they occur. Upon detecting a collision, devices stop transmitting, wait a random period, and then retransmit, effectively preventing simultaneous transmissions and managing shared media access.

What are the REST's primary characteristics?

Answer: All of them

REST (Representational State Transfer) is an architectural style for designing networked applications, particularly web services. Its primary characteristics include being lightweight due to its use of standard HTTP methods, flexible in handling various data formats, platform-agnostic as it can be implemented across different technologies, and scalable because of its stateless nature. These attributes make REST a popular choice for modern API design.

Instead of SNMP, SDN uses ____ as a network configuration management protocol.

Answer: Netconf

SDN (Software-Defined Networking) centralizes network control and management, requiring programmatic configuration capabilities. While SNMP is primarily for monitoring, NETCONF (Network Configuration Protocol) is an XML-based protocol specifically designed for configuring network devices. It offers robust, programmatic configuration management, making it a suitable protocol for the automated and centralized control plane of SDN architectures.

To learn an unknown MAC address, what does a PC broadcast?

Answer: ARP Request

When a PC needs to communicate with another device on the same local network but does not know its MAC address, it uses ARP (Address Resolution Protocol). The PC broadcasts an ARP Request packet containing the target device's IP address. The device with that specific IP address then responds with an ARP Reply, providing its MAC address to the requesting PC.

The ____ protocol is used to manage network devices.

Answer: SNMP

SNMP (Simple Network Management Protocol) is a widely used application-layer protocol for managing and monitoring network devices. It allows network administrators to collect information, modify configurations, and receive alerts about the status of routers, switches, servers, and other network equipment. SNMP is crucial for network operations, performance monitoring, and troubleshooting.

Which of the following protocols is a Distance Vector Protocol?

Answer: RIP

Distance Vector routing protocols determine the best path to a destination based on the 'distance' (e.g., hop count) and the 'direction' (vector) to reach it, typically relying on information from directly connected neighbors. RIP (Routing Information Protocol) is a classic example of a distance vector protocol, using hop count as its primary metric and periodically exchanging full routing tables with its neighbors.

To identify traffic bottlenecks between two sites, which router command is used?

Answer: Trace

The `traceroute` (or `trace` on Cisco devices, `tracert` on Windows) command is used to display the path and measure transit delays of packets across an IP network. By showing each router (hop) a packet traverses and the round-trip time to each hop, it helps identify where delays or bottlenecks might be occurring between two sites. This makes it ideal for diagnosing connectivity and performance issues.

What are some examples of Denial of Service Attacks? (Choose three)

Answer: Smurfing

Denial of Service (DoS) attacks aim to make a network service unavailable to legitimate users. A TCP SYN Flood overwhelms a server by sending numerous SYN requests without completing the three-way handshake. A Ping of Death involves sending oversized or malformed ICMP packets that can crash older systems. Smurfing is a distributed DoS attack that uses ICMP echo requests directed at an IP broadcast address to amplify traffic to a victim.

If Dynamic ARP Inspection (DAI) is enabled,.... is checked, and this ARP packet is permitted if the incoming MAC address is in this table.

Answer: IP-MAC Binding Table

Dynamic ARP Inspection (DAI) is a security feature that prevents ARP spoofing and poisoning attacks by validating ARP packets. When DAI is enabled, it checks incoming ARP packets against the IP-MAC binding table, which is often populated by DHCP snooping. If an ARP packet's source IP-MAC address pair does not match an entry in this trusted table, the packet is dropped, preventing unauthorized ARP traffic.

If each site has a centralized WLAN Controller and Access Points attached to it, this is...

Answer: Centralized Wireless Network Design

In a centralized wireless network design, a single or cluster of WLAN controllers manages all access points (APs) across different sites. The APs act as 'thin' clients, forwarding all wireless traffic to the central controller for processing, security, and management. This architecture simplifies management, provides consistent policy enforcement, and centralizes control over the entire wireless infrastructure.

True/False: The Internet Protocol (IP) is a connectionless protocol.

Answer: B) True

The Internet Protocol (IP) is a connectionless protocol, meaning that each packet is treated independently without any prior connection establishment or guarantee of delivery. IP focuses on efficient, best-effort delivery of individual datagrams across networks. Reliability, ordering, and error checking are handled by higher-layer protocols like TCP.

What is the broadcast address for a 192.168.145.0 Class C address with the default Subnet Mask?

Answer: 192.168.145.255

For a Class C address like 192.168.145.0 with the default subnet mask (255.255.255.0 or /24), the first three octets identify the network (192.168.145). The last octet is reserved for host addresses. The broadcast address is obtained by setting all host bits to 1, which for the last octet means 255. Therefore, the broadcast address is 192.168.145.255.

What protocols are Link State Routing?

Answer: OSPF

Link-state routing protocols build a complete topological map of the network. Each router exchanges Link State Advertisements (LSAs) with all other routers in its area, describing its directly connected links and their states. OSPF (Open Shortest Path First) and IS-IS (Intermediate System to Intermediate System) are the two most prominent examples of link-state routing protocols, known for their fast convergence and efficient routing.