1.
(201) At what Open System Interconnection (OSI) layer are virtual circuits established, maintained and terminated?
Correct Answer
D. Transport.
Explanation
Virtual circuits are established, maintained, and terminated at the Transport layer of the Open System Interconnection (OSI) model. The Transport layer is responsible for end-to-end communication and provides reliable and ordered delivery of data packets. It establishes virtual circuits, which are logical connections between two endpoints, and ensures that the data is delivered accurately and efficiently. The Network layer is responsible for routing and addressing, the Physical layer deals with the physical transmission of data, and the Data Link layer handles framing and error detection.
2.
(201) Which of the following is an example of a video compression standard?
Correct Answer
A. Motion Picture Experts Group–4 (MPEG–4).
Explanation
MPEG-4 is a video compression standard developed by the Motion Picture Experts Group. It is widely used for video streaming, video conferencing, and multimedia storage. It allows for efficient compression of video files while maintaining good quality. JPEG, on the other hand, is a compression standard for still images, not videos. FTP is a protocol used for transferring files, and G.711 is a standard for audio compression, not video compression. Therefore, the correct answer is Motion Picture Experts Group–4 (MPEG–4).
3.
(202) In the Open System Interconnect (OSI) model, a layer will communicate with three other OSI layers. Which one is not one of those layers?
Correct Answer
C. Lowest layer.
Explanation
In the Open System Interconnect (OSI) model, a layer communicates with the layer above it, the layer below it, and its peer layer. The lowest layer refers to the physical layer, which is responsible for the actual transmission and reception of data. Since it does not communicate with any other layer below it, the lowest layer is not one of the layers that a layer communicates with.
4.
(203) What data communication protocol uses characters or “handshaking” to control the link and represent information?
Correct Answer
B. Binary synchronous protocol.
Explanation
Binary synchronous protocol is a data communication protocol that uses characters or "handshaking" to control the link and represent information. This protocol ensures reliable and error-free transmission of data by using synchronization characters and checksums. It provides flow control, error detection, and error correction mechanisms, making it suitable for applications that require high reliability and accuracy in data transmission.
5.
(203) In binary-synchronous protocol, which characters establishes and maintains character synchronization prior to the message block and during transmission?
Correct Answer
B. SYN.
Explanation
In binary-synchronous protocol, the SYN (synchronize) character is used to establish and maintain character synchronization prior to the message block and during transmission. This character ensures that the sender and receiver are in sync and ready to transmit or receive data. It serves as a signal to indicate the start of a message and helps to maintain the integrity of the data being transmitted.
6.
(203) Which data communication protocol is based on bits and the position of the bits?
Correct Answer
B. Bit-oriented.
Explanation
Bit-oriented data communication protocol is based on the position of the bits. In this protocol, data is transmitted and received bit by bit, where each bit carries information and has a specific position within the data stream. This allows for efficient and accurate data transmission, as the protocol focuses on the individual bits rather than characters or larger data units.
7.
(203) Which data communication protocol is a transmission code that supports a variety of link types and topologies?
Correct Answer
C. Synchronous Data Link Control (SDLC).
Explanation
SDLC (Synchronous Data Link Control) is a data communication protocol that supports a variety of link types and topologies. It is a synchronous protocol, meaning that data is transmitted in a synchronized manner with the sender and receiver using the same clock signal. SDLC is widely used in communication systems and networks, providing reliable and efficient data transmission. It is capable of supporting different link types and topologies, making it a versatile protocol for various applications.
8.
(204) Which network layer protocol matches a known Internet protocol (IP) address for a destination device to a Media Access Control (MAC) address?
Correct Answer
B. Address Resolution Protocol (ARP).
Explanation
The correct answer is Address Resolution Protocol (ARP). ARP is a network layer protocol that matches a known IP address for a destination device to a MAC address. It is used to find the MAC address of a device on the same network by broadcasting an ARP request. Once the MAC address is resolved, the device can communicate with the destination device using the MAC address.
9.
(204) Which Network layer protocol provides messaging that can help with troubleshooting?
Correct Answer
D. Internet Control Message Protocol (ICMP).
Explanation
ICMP is a network layer protocol that provides messaging services for troubleshooting purposes. It is used to send error messages and operational information about network conditions between devices on an IP network. ICMP messages are used to diagnose network connectivity issues, identify network congestion, and troubleshoot network problems. It allows network administrators to monitor network performance, detect and isolate network errors, and gather information about network devices. Therefore, ICMP is the correct answer as it provides messaging that can help with troubleshooting.
10.
(204) Which Transport layer protocol provides reliable data delivery services?
Correct Answer
C. Transmission Control Protocol (TCP).
Explanation
The correct answer is Transmission Control Protocol (TCP). TCP provides reliable data delivery services by ensuring that data packets are delivered in the correct order and without errors. It uses mechanisms such as acknowledgment, retransmission, and flow control to ensure reliable transmission. Unlike UDP, which is a connectionless protocol and does not provide reliability, TCP establishes a connection between the sender and receiver and guarantees the delivery of data. Therefore, TCP is the correct choice for reliable data delivery services.
11.
(204) Which Application layer protocol is used to synchronize the clocks of computers on a network?
Correct Answer
C. Network Time Protocol (NTP).
Explanation
Network Time Protocol (NTP) is used to synchronize the clocks of computers on a network. NTP is designed to accurately synchronize the timekeeping of networked computers by exchanging time information between them. It allows computers to maintain consistent and accurate time, which is crucial for various network operations and applications that rely on synchronized time. SNMP is used for network management, DHCP is used for automatic IP address assignment, and PING is used for network troubleshooting. Therefore, NTP is the correct choice for clock synchronization.
12.
(205) Which network Class has the most addresses for hosts?
Correct Answer
A. A.
Explanation
Class A network has the most addresses for hosts. This is because Class A networks have a very large range of IP addresses, with the first octet reserved for network identification and the remaining three octets available for host addresses. The first octet can have a range from 1 to 126, allowing for a maximum of 126 different Class A networks, each with millions of possible host addresses.
13.
(205) How many subnet bits are required to support 90 subnets on a Class B network?
Correct Answer
C. Seven.
Explanation
To support 90 subnets on a Class B network, we need to determine the number of subnet bits required. In a Class B network, the default subnet mask is 16 bits for the network portion. To calculate the number of subnet bits needed, we use the formula 2^n >= number of subnets, where n is the number of subnet bits. In this case, 2^n >= 90. By trying different values of n, we find that 2^7 = 128, which is greater than 90. Therefore, we need 7 subnet bits to support 90 subnets on a Class B network.
14.
(206) Internet protocol version 6 (IPv6) addresses are represented by
Correct Answer
B. 8 groups of hexadecimal numbers.
Explanation
IPv6 addresses are represented by 8 groups of hexadecimal numbers. This is because IPv6 uses a 128-bit address format, which is much larger than the 32-bit address format used by IPv4. Hexadecimal numbers are used because they provide a more compact representation of the large address space, compared to decimal numbers. Each group of hexadecimal numbers is separated by a colon, allowing for a total of 8 groups in an IPv6 address.
15.
(206) Teredo has four tunneling components. Which one is not one of them?
Correct Answer
D. Agent.
Explanation
The question asks for the tunneling component that is not part of Teredo. Teredo is a tunneling protocol used to enable IPv6 connectivity over IPv4 networks. The components mentioned in the options, such as host-specific relay, client, and server, are all part of Teredo. However, "agent" is not a recognized tunneling component in the context of Teredo. Therefore, the correct answer is "Agent."
16.
(207) Which device has multiport connectivity that directs data between nodes on a network?
Correct Answer
B. Router.
Explanation
A router is a device that has multiport connectivity and directs data between nodes on a network. It is responsible for forwarding data packets between computer networks, ensuring that they reach their intended destinations. Unlike a bridge, which connects two similar types of networks, a router can connect different types of networks, such as Ethernet and Wi-Fi. A gateway, on the other hand, is a device that connects two different types of networks, such as a local area network (LAN) and the internet. A repeater is a device that amplifies or regenerates a signal to extend its reach in a network but does not direct data between nodes.
17.
(207) Which routing protocol do internet backbones use?
Correct Answer
A. Border Gateway Protocol (BGP).
Explanation
Internet backbones use Border Gateway Protocol (BGP) as their routing protocol. BGP is specifically designed for routing between autonomous systems (AS) and is used to exchange routing information and maintain a table of available routes. It is highly scalable and can handle the large number of routes and complex network topologies typically found in internet backbones. BGP also supports policy-based routing, allowing network administrators to control the flow of traffic and implement advanced routing policies. OSPF, RIP, and EIGRP are other routing protocols used within individual ASs but are not commonly used in internet backbones.
18.
(208) Which router port is used for initial configuration?
Correct Answer
B. Console.
Explanation
The console port on a router is used for initial configuration. This port allows direct access to the router's command-line interface (CLI) through a console cable. By connecting a computer to the console port using a console cable, network administrators can configure the router's settings, such as IP addresses, routing protocols, and security settings, before enabling other ports for network connectivity. The console port provides a reliable and secure method for initial setup and troubleshooting of the router.
19.
(208) When configuring a router, you control access to privileged EXEC mode by configuring which password?
Correct Answer
C. Enable.
Explanation
When configuring a router, access to privileged EXEC mode is controlled by configuring the "enable" password. This password is used to authenticate users who want to access the privileged EXEC mode, which provides full control and configuration capabilities on the router. By setting an enable password, only authorized users who know the password can access this mode and make changes to the router's configuration.
20.
(208) On a router’s serial interface connection, what provides the timing signal for the communication link?
Correct Answer
A. Data communications equipment.
Explanation
Data communications equipment provides the timing signal for the communication link on a router's serial interface connection. This equipment is responsible for transmitting and receiving data over the network, and it also ensures that the timing is synchronized between the sender and receiver. By providing the timing signal, data communications equipment helps to maintain the accuracy and reliability of the communication link.
21.
(209) Virtual Private Networks (VPNs) allow the AF to extend network resources across a/an
Correct Answer
D. A public network.
Explanation
VPNs allow the AF to extend network resources across a public network. This means that the AF can securely connect to and access network resources from any location using the internet as the underlying infrastructure. By encrypting the data transmitted over the public network, VPNs ensure that the communication remains secure and private. This allows the AF to connect to and utilize network resources even when they are not physically present on the same network, providing flexibility and remote access capabilities.
22.
(210) Which topology defines the way in which devices communicate and data is transmitted throughout the network?
Correct Answer
B. Logical.
Explanation
Logical topology defines the way in which devices communicate and data is transmitted throughout the network. It represents the logical connections between devices, regardless of their physical locations. It determines how data flows from one device to another and how devices are organized in a network. Unlike physical topology, which refers to the actual physical layout of devices and cables, logical topology focuses on the conceptual structure of the network. Common examples of logical topologies include bus, ring, star, mesh, and tree.
23.
(210) Which topology has the stations connected in the form of a circle?
Correct Answer
B. Ring.
Explanation
In a ring topology, the stations are connected in the form of a circle, where each station is connected to exactly two other stations. Data is transmitted in only one direction around the ring, and each station acts as a repeater to amplify and pass on the signal to the next station. This topology provides equal access to all stations and allows for efficient data transmission.
24.
(210) Which topology combines two or more different physical topologies in a single network?
Correct Answer
D. Hybrid.
Explanation
A hybrid topology combines two or more different physical topologies in a single network. This means that a network can have a combination of bus, ring, star, or other topologies. By using a hybrid topology, organizations can customize their network to meet their specific needs and requirements. This allows for greater flexibility and scalability in network design.
25.
(211) Which device subdivides a network into smaller logical pieces, or segments?
Correct Answer
A. Switch.
Explanation
A switch is a device that subdivides a network into smaller logical pieces or segments. It operates at the data link layer of the OSI model and allows for the efficient and secure transfer of data between devices within a network. Unlike a hub, which broadcasts data to all devices on a network, a switch intelligently directs data packets only to the intended recipient, improving network performance and security. Therefore, a switch is the correct answer for this question.
26.
(211) The time it takes a switch to figure out where to forward a data unit is called its
Correct Answer
C. Latency.
Explanation
Latency refers to the time it takes for a switch to determine the appropriate destination for a data unit. It measures the delay between the initiation of a request and the response received. Lag refers to a delay or pause in the transmission of data, hop refers to the process of forwarding a data unit from one network node to another, and time zone is unrelated to the switch's decision-making process.
27.
(211) Which of the following is not a distinct layer of a hierarchical network design?
Correct Answer
C. Transport.
Explanation
The correct answer is Transport. In a hierarchical network design, the three distinct layers are Core, Distribution, and Access. The Core layer is responsible for high-speed backbone connectivity, the Distribution layer provides routing and filtering functions, and the Access layer connects end devices to the network. The Transport layer, on the other hand, is a layer in the OSI model that handles end-to-end communication between devices and is not specifically related to the hierarchical network design.
28.
(211) How many broadcast domains forms a Virtual LAN (VLAN)?
Correct Answer
A. 1
Explanation
A Virtual LAN (VLAN) is a logical grouping of devices in a network that behave as if they are on their own independent network, even though they may physically be connected to the same switch. By creating VLANs, network administrators can separate traffic and improve network performance and security. Each VLAN forms its own broadcast domain, meaning that broadcast traffic is contained within that VLAN and does not propagate to other VLANs. Therefore, a single VLAN forms one broadcast domain.
29.
(211) What allows transportation of all active Virtual LANs (VLAN) between switches using a single physical link?
Correct Answer
A. VLAN trunks.
Explanation
VLAN trunks allow transportation of all active VLANs between switches using a single physical link. A VLAN trunk is a network link that can carry traffic for multiple VLANs simultaneously. It uses a tagging mechanism to identify which VLAN a particular frame belongs to, allowing multiple VLANs to be transported over the same physical link. This enables efficient use of network resources and simplifies network management by reducing the number of physical links required to connect switches.
30.
(211) Which of the following will minimize EtherChannel configuration problems?
Correct Answer
B. Configure all interfaces to operate at the same speed and duplex mode.
Explanation
Configuring all interfaces to operate at the same speed and duplex mode will minimize EtherChannel configuration problems. This ensures that all interfaces in the EtherChannel have consistent settings, preventing any mismatch or conflicts that could lead to configuration problems. By operating at the same speed and duplex mode, the interfaces can effectively communicate and share the load in the EtherChannel without any issues.
31.
(212) Which Institute of Electrical Electronics Engineers (IEEE) specification is least susceptible to interference caused by household appliances and medical devices?
Correct Answer
A. 802.11a.
Explanation
The IEEE specification 802.11a is least susceptible to interference caused by household appliances and medical devices. This is because it operates on the 5 GHz frequency band, which is less crowded and has less interference compared to the 2.4 GHz frequency band used by 802.11b and 802.11g. 802.11r is a specification for fast roaming in Wi-Fi networks and is not related to interference susceptibility.
32.
(212) Which wireless design phase accounts for the amount of users on the network, the training required for the users and the security and integrity requirements of the network data?
Correct Answer
A. Planning.
Explanation
The wireless design phase that accounts for the amount of users on the network, the training required for the users, and the security and integrity requirements of the network data is planning. During the planning phase, all these factors are taken into consideration to ensure that the wireless network is designed and implemented in a way that meets the needs of the users, while also maintaining the necessary security measures and data integrity. This phase involves analyzing the requirements, conducting a site survey, and creating a detailed plan for the wireless network deployment.
33.
(212) What identifier differentiates one wireless local area network (WLAN) from another?
Correct Answer
C. Service Set Identifier (SSID).
Explanation
The Service Set Identifier (SSID) is the correct answer because it is the identifier that differentiates one wireless local area network (WLAN) from another. The SSID is a unique name assigned to a WLAN, allowing devices to connect to the correct network. The hostname is a label assigned to a device on a network, not specific to WLANs. The network name is a general term and does not specifically differentiate WLANs. The Virtual LAN Identifier (VLAN ID) is used to separate network traffic within a LAN, but it does not differentiate WLANs from each other.
34.
(213) A Management Information Base (MIB) is a collection of information that is organized
Correct Answer
B. Hierarchically.
Explanation
A Management Information Base (MIB) is a collection of information that is organized hierarchically. This means that the information is structured in a hierarchical manner, with different levels of information grouped together based on their relationships and dependencies. This hierarchical organization allows for easier management and access to the information within the MIB, as it provides a clear structure and framework for organizing and navigating the data.
35.
(213) Simple Network Management Protocol (SNMP) is a tool used by network administrators to manage network performance, investigate and solve network problems and help plan for
Correct Answer
A. Future growth.
Explanation
SNMP is a tool used by network administrators to manage network performance, investigate and solve network problems, and help plan for future growth. This means that SNMP helps administrators in monitoring and analyzing the current network performance, identifying and resolving any issues or problems that may arise, and also assists in making informed decisions regarding the expansion or scalability of the network infrastructure to accommodate future growth.
36.
(214) Which physical security action can you take to ensure network equipment supports the widest range of security services?
Correct Answer
A. Configure the equipment with the maximum amount of memory possible.
Explanation
By configuring the equipment with the maximum amount of memory possible, it ensures that the network equipment has enough storage capacity to support a wide range of security services. These security services may include encryption, authentication, access control, and intrusion detection, among others. Having more memory allows the equipment to handle the processing and storage requirements of these services effectively, ensuring the network's security is not compromised.
37.
(214) In general, you should deny direct dial-in access to a network device by disabling which port?
Correct Answer
B. Auxiliary.
Explanation
The correct answer is Auxiliary. Direct dial-in access to a network device should be denied by disabling the Auxiliary port. The Auxiliary port is typically used for out-of-band management and remote access, so disabling it would prevent unauthorized access to the network device. The Console port is used for local management and configuration, the Interface ports are used for connecting to other network devices, and the Virtual terminal is used for remote management, but none of these ports are specifically designed for direct dial-in access like the Auxiliary port.
38.
(215) Individual pulses within a digital signal are
Correct Answer
A. Bits.
Explanation
Individual pulses within a digital signal are represented as bits. In digital communication, information is transmitted in the form of binary digits (bits) which can have two possible values, 0 or 1. Each pulse within a digital signal represents either a 0 or a 1, allowing for the transmission and storage of data in a digital format. Therefore, bits are the correct answer as they represent the individual pulses within a digital signal.
39.
(215) What is most commonly used in data systems to express signaling speed?
Correct Answer
C. Bits per second.
Explanation
Bits per second is the most commonly used term in data systems to express signaling speed. It represents the number of bits that can be transmitted or processed in one second. Baud rate, on the other hand, refers to the number of signal changes per second and is not the same as the number of bits transmitted. Interface speed and Baud per second are not commonly used terms in data systems and are not as accurate as bits per second for expressing signaling speed.
40.
(216) Which option is a characteristic of synchronous data operation?
Correct Answer
D. All data bits are the same length in time.
Explanation
A characteristic of synchronous data operation is that all data bits are the same length in time. This means that each bit within the data stream is transmitted and received at the same predetermined time interval. This ensures that the sender and receiver are synchronized and can accurately interpret the data being transmitted. The uniform length of data bits allows for efficient and reliable data transmission, as it eliminates the need for additional start and stop pulses or timing pulses within the signal stream. System timing becomes critical in synchronous data operation to maintain synchronization between sender and receiver.
41.
(216) A digital signal that contains synchronizing bits within the signal stream describes
Correct Answer
B. Asynchronous operation.
Explanation
A digital signal that contains synchronizing bits within the signal stream describes asynchronous operation. This is because synchronizing bits are used to maintain the timing and synchronization between the sender and receiver in asynchronous communication. Asynchronous operation allows for the transmission of data without the need for a continuous clock signal, as the synchronizing bits help the receiver identify the start and end of each data packet.
42.
(217) How many voltage levels does a binary signal have?
Correct Answer
B. 2
Explanation
A binary signal has two voltage levels, typically represented as 0 and 1. This is because binary signals are based on the binary number system, which uses only two digits (0 and 1) to represent information. Each voltage level corresponds to one of these digits, allowing for the representation of digital information in computers and electronic devices.
43.
(217) In what type of digital signal does the signal level move to one of the discrete signal levels, but returns to the zero level after a predetermined time?
Correct Answer
D. Return-to-zero.
Explanation
In a return-to-zero (RZ) digital signal, the signal level moves to one of the discrete signal levels (usually positive or negative) and then returns to the zero level after a predetermined time. This means that the signal alternates between the two levels and includes a zero level in between each transition. This type of signal is commonly used in digital communication systems to represent binary data, where the presence of a signal level represents a "1" and the absence of a signal level represents a "0".
44.
(218) Digital coding techniques such as binary with eight-zero substitution (B8ZS) are becoming more popular because they are designed to
Correct Answer
D. Maintain ones density standards.
Explanation
Digital coding techniques such as binary with eight-zero substitution (B8ZS) are becoming more popular because they are designed to maintain ones density standards. This means that they ensure a balanced number of ones and zeros in the transmitted data, which is important for maintaining the integrity of the signal and preventing errors. By maintaining ones density standards, these coding techniques help to minimize the risk of signal degradation and ensure reliable communication.
45.
(218) Which statement best describes a binary with eight-zero substitution (B8ZS) signal?
Correct Answer
D. Bipolar violations are intentionally inserted into a data signal to break up long strings of zeros.
Explanation
A B8ZS signal is a type of line code used in telecommunications to transmit digital data. It is designed to break up long strings of zeros by intentionally inserting bipolar violations. This helps to maintain synchronization and prevent errors in the transmission.
46.
(219) How many bits are in the extended superframe format (ESF) framing sequence?
Correct Answer
C. 24
Explanation
The extended superframe format (ESF) framing sequence consists of 24 bits.
47.
(220) The signaling equipment has three types of communications signals that functions to
Correct Answer
C. Control and process calls.
Explanation
The signaling equipment has three types of communication signals that control and process calls. This means that the equipment is responsible for managing and directing calls, ensuring that they are properly routed and connected. It does not specifically mention switch addressing or digit translations, so these options can be ruled out. Providing a clear signal is not mentioned as a specific function of the signaling equipment in this context.
48.
(220) Which communications control signal uses a two-frequency dialing combination?
Correct Answer
B. Tone.
Explanation
The correct answer is "Tone" because the question is asking about a communications control signal that uses a two-frequency dialing combination. Pulse, digit, and address do not fit this description. Tone signals, on the other hand, are generated by combining two frequencies and are commonly used in telephone systems for dialing.
49.
(221) In common associated signaling (CAS), what is the seventh bit in frames 6 and 12 used for?
Correct Answer
A. Bit robbing.
Explanation
In common associated signaling (CAS), the seventh bit in frames 6 and 12 is used for "Bit robbing". Bit robbing refers to the process of stealing the least significant bit from the sixth frame and using it as the seventh bit in frames 6 and 12. This technique is used to increase the capacity of the signaling system by utilizing existing bits in a more efficient manner.
50.
(221) How is supervisory signaling information transferred in common channel signaling (CCS)?
Correct Answer
D. Separate network channel.
Explanation
In common channel signaling (CCS), supervisory signaling information is transferred through a separate network channel. This means that the signaling information is transmitted separately from the voice or data channels, allowing for more efficient and reliable communication. By using a separate network channel, the signaling information can be transmitted without interfering with the main communication channels, ensuring that the supervisory signals are accurately and efficiently transmitted between the communicating parties.