COMP TIA NETWORK + Version 9.1 Flashcards
1.1.9
Which of the following networking terms refers to the nodes that send and receive data traffic?
A.) End systems
B.) Intermediate nodes
C.) Network protocols
D.) Network links
A.) End systems
End systems, also referred to as hosts, are the nodes that send and receive data traffic in a network. They consume the services provided by servers in a client-server network.
Intermediate nodes perform a forwarding function in a network. They help to route the data but do not send or receive data traffic themselves.
Network links refer to the communication pathways between nodes in a network. They do not send or receive data traffic themselves.
Network protocols are sets of rules that govern data communication over a network. They do not send or receive data traffic.
1.1.9
You own a small business and have decided to set up a network where each computer acts as both a client and a server.
This decentralized model should allow for the provisioning, management, and security of services and data that you want distributed around the network.
What type of network would BEST meet your requirements?
A.) Peer-to-Peer network
B.) Incorrect answer:
C.) Client-Server network
D.) Enterprise network
E.) Virtual Private network
A.) Peer-to-Peer network
A Peer-to-Peer network would best meet your requirements. In a peer-to-peer network, each host acts as both a client and a server. This is a decentralized model where provision, management, and security of services and data is distributed around the network, which matches the scenario described.
In a client-server network, servers are more powerful computers that make network applications and resources available to other hosts, while clients consume the services provided by servers. This does not match the scenario described where each computer acts as both a client and a server.
A virtual private network (VPN) is a network that is constructed using public wires (usually the Internet) to connect to a private network, such as a company’s internal network. This does not match the scenario described where each computer acts as both a client and a server.
An enterprise network is a large corporate network that supports many users and comprises many different networks. The network setup described in the scenario does not match the characteristics of an enterprise network.
1.1.9
A growing company has recently moved into a new office space. The company has 50 employees, each with their own workstation. The office also has multiple printers, a centralized server, and requires structured cabling for connectivity.
Which type of network would be MOST effective for this setup?
A.) Data Center
B.) Small Office/Home Office (SOHO) network
C.) Small and Medium-sized Enterprise (SME) network
D.) Wide Area Network (WAN)
C.) Small and Medium-sized Enterprise (SME) network
A Small and Medium-sized Enterprise (SME) network is the correct answer. An SME network is designed to support dozens of users and would use structured cabling and multiple switches and routers to provide connectivity. This is the most suitable type of network for a company with 50 employees.
Small Office/Home Office (SOHO) networks are typically designed for smaller setups, often using a single Internet router/switch/access point to provide connectivity. A company with 50 employees would likely require a more robust network setup.
Wide Area Networks (WANs) are typically used to connect multiple networks over long distances, such as connecting a main office site with multiple branch office sites, possibly in different countries. This is not the case for a company with a single office.
A data center is a network that hosts only servers and storage, not end user client devices. In this scenario, the office has end user client devices (the employees’ workstations), so a data center would not be appropriate.
1.1.9
A multinational corporation has its main office in New York and branch offices in London, Tokyo, and Sydney. The corporation needs a network that can connect all these offices together, allowing for seamless communication and data transfer.
Which type of network would be MOST suitable for this setup?
A.) Local Area Network (LAN)
B.) Small and Medium-sized Enterprise (SME) network
C.) Wide Area Network (WAN)
D.) Small Office/Home Office (SOHO) network
C.) Wide Area Network (WAN)
Wide Area Network (WAN) is the correct answer. A WAN is a network of networks, connected by long-distance links. A typical enterprise WAN would connect a main office site with multiple branch office sites, possibly in different countries. This is the most suitable type of network for a multinational corporation with offices in different countries.
A Local Area Network (LAN) is confined to a single geographical location and all nodes and segments are directly connected with cables or short-range wireless technologies. It would not be suitable for connecting offices in different countries.
A Small Office/Home Office (SOHO) network is designed for a small number of users in a single location, often using a single Internet router/switch/access point to provide connectivity. It would not be suitable for connecting multiple offices in different countries.
A Small and Medium-sized Enterprise (SME) is designed to support dozens of users in a single location, using structured cabling and multiple switches and routers to provide connectivity. It would not be suitable for connecting multiple offices in different countries.
1.1.9
When referencing network topologies, what distinguishes half-duplex from full-duplex communication in a point-to-point link?
A.) Half-duplex communication uses a single cable for data transmission, whereas full-duplex requires separate cables for each direction.
B.) Half-duplex allows for data transmission in both directions, but not simultaneously; full-duplex permits simultaneous two-way data transmission.
C.) Half-duplex communication can only occur in one direction, while full-duplex allows for data transmission in both directions but not at the same time.
D.) Full-duplex communication is limited to one direction at a time, similar to half-duplex, but it operates at higher speeds.
B.) Half-duplex allows for data transmission in both directions, but not simultaneously; full-duplex permits simultaneous two-way data transmission.
The correct answer is half-duplex allows for data transmission in both directions, but not simultaneously; full-duplex permits simultaneous two-way data transmission.
Half-duplex communication can only occur in one direction, while full-duplex allows for data transmission in both directions but not at the same time is incorrect. It inaccurately states that half-duplex communication can only occur in one direction. Half-duplex does allow for two-way communication, but with the limitation that it cannot happen simultaneously.
Full-duplex communication is limited to one direction at a time, similar to half-duplex, but it operates at higher speeds is incorrect. It confuses the capabilities of full-duplex communication. Full-duplex systems can indeed transmit data in both directions simultaneously, not just one direction at a time. The speed of the communication is not the defining difference between half-duplex and full-duplex.
Half-duplex communication uses a single cable for data transmission, whereas full-duplex requires separate cables for each direction is incorrect. It suggests that the use of separate cables is what differentiates half-duplex from full-duplex communication. The distinction between half-duplex and full-duplex is not about the number of cables used but about whether data transmission can occur simultaneously in both directions.
1.1.9
Your company has a network where all devices can communicate with each other as if they were directly connected, regardless of the physical connections.
Your company has a network where all devices can communicate with each other as if they were directly connected, regardless of the physical connections.
What type of network topology does this describe?
A.) Ring topology
B.) Star topology
C.) Mesh topology
D.) Logical topology
D.) Logical topology
Logical topology is the correct answer. A logical topology describes the flow of data through the network. In the scenario, each device can send messages to any other device on the network, which is a characteristic of a logical topology.
A star topology is a type of physical topology where each device on the network is connected to a central node or switch. While the scenario describes a network that physically resembles a star topology, the question is asking for the type of network topology that describes the flow of data, which is a logical topology.
In a mesh topology, every device is connected to every other device on the network. This is not the case in the scenario described.
In a ring topology, each device is connected to exactly two other devices, forming a ring. This is not the case in the scenario described.
1.1.9
You manage a network that’s connected using a physical star topology. One of the drop cables connecting a workstation has been removed.
Which of the following BEST describes the effect that this will have on network communications?
A.) All devices except the device connected with the drop cable will be able to communicate.
B.) Devices on one side of the missing cable will be able to communicate with each other, while devices on the other side of the missing cable will not be able to communicate.
C.) No devices will be able to communicate.
D.) Only devices on one side of the missing cable will be able to communicate with each other, while only devices on the other side of the missing cable will be able to communicate with each other.
E.) All devices will be able to communicate.
A.) All devices except the device connected with the drop cable will be able to communicate.
A cable break in a star topology means that the device connected to the central device (hub or switch) through that cable can no longer communicate on the network. All other hosts will be able to communicate with all other devices.
1.1.9
Which of the following networking topologies connects each network device to a central forwarding appliance?
A.) Ring
B.) Mesh
C.) Star
D.) Bus
C.) Star
Star topologies connect each device on a network to a central forwarding appliance.
In ring topologies, each device connects to a neighboring device so that a ring is formed.
A bus topology connects all devices to a trunk cable.
A mesh topology exists when there are multiple paths between any two nodes on a network.
1.1.9
You have a network that’s connected using a full physical mesh topology. The link between Device A and Device B is broken.
Which of the following BEST describes the effect that this will have on network communications?
A.) Device A will not be able to communicate with any other device.
B.) Device A will be able to communicate with any device except for Device B.
C.) Device A will be able to communicate with all other devices.
D.) No devices will be able to communicate with any other device.
C.) Device A will be able to communicate with all other devices.
With a mesh topology, a break in a single link has no effect on communications. Data can be routed to the destination device by taking a different (sometimes longer) path through the mesh topology.
1.1.9
You’ve implemented an ad hoc wireless network that doesn’t employ a wireless access point. Every wireless network card can communicate directly with any other wireless network card on the network.
Which type of physical network topology have you implemented in this network?
A.) Mesh
B.) Star
C.) Bus
D.) Ring
A.) Mesh
This type of network uses a physical mesh topology. A mesh topology has two key characteristics, which are that there’s no central connecting point, and any host can communicate directly with any other host on the network.
A mesh network is usually impractical on a wired network. Each host would require a separate dedicated network interface and cable. But you can implement a mesh topology with relative ease on a wireless network because wires aren’t an issue.
A ring topology connects neighboring nodes until they form a ring. Signals travel in one direction around the ring.
A star topology uses a hub or switch to connect all network connections to a single physical location.
A bus topology consists of a trunk cable with nodes either inserted directly into the trunk or tapped in with offshoot cables called drop cables.
1.1.9
A team of network consultants is configuring an Internet of Things (IoT) network. The team is considering network topologies in the context of the IoT devices being used, which are all within 100 meters of one another, are battery-powered, and communicate via the Zigbee protocol.
Which of the following network topologies would BEST save power and scale easily to thousands of IoT sensor devices while saving power by cooperating with nearby devices?
A.) Ring
B.) Mesh
C.) Bus
D.) Star
B.) Mesh
Mesh networks provide excellent redundancy, because other routes, via intermediary devices, are available between locations if a link failure occurs.
In a star topology, each endpoint node is connected to a central forwarding node, such as a hub, switch, or router. The central node mediates communications between the endpoints.
A physical bus topology is a shared access topology, meaning that all nodes share the bandwidth of the media. All nodes attach directly to a single cable segment via cable taps.
In a physical ring topology, each node is wired to its neighbor in a closed loop. A node receives a transmission from its upstream neighbor and passes it to its downstream neighbor until the transmission reaches its intended destination.
1.2.9
Which of the following are layers of the OSI reference model? (Select three.)
A.) Connection Layer
B.) Encryption Layer
C.) Application Layer
D.) Transmission Layer
E.) Session Layer
F.) Presentation Layer
G.) WAN Layer
C.) Application Layer
E.) Session Layer
F.) Presentation Layer
The Application Layer is the seventh layer of the OSI model and provides network services directly to the user’s applications, such as email, file transfer, and other network software services.
The Presentation Layer is the sixth layer of the OSI model and is responsible for the translation, encryption, and compression of data. It ensures that data is in a readable format for the Application Layer.
The Session Layer is the fifth layer of the OSI model and establishes, manages, and terminates connections between applications. It is responsible for setting up, coordinating, and terminating conversations, exchanges, and dialogues between the applications at each end.
Transmission Layer is not a layer of the OSI model. This might be confused with the Transport Layer, which is the fourth layer of the OSI model and is responsible for providing transparent transfer of data between end systems.
Encryption Layer is not a layer of the OSI model. Encryption can occur at several layers, including the Presentation Layer and the Application Layer, but it is not a separate layer.
WAN is a Wide Area Network and describes a network topology and not a layer in the OSI model.
Connection Layer is not a layer of the OSI model. This might be confused with the Data Link Layer, which is the second layer of the OSI model and provides node-to-node data transfers between two directly connected nodes.
1.2.9
What is a Protocol Data Unit (PDU)?
A.) A type of encryption used in data transmission
B.) A chunk of data with protocol-specific headers added at each OSI layer
C.) A device that manages data transmission rates
D.) A measure of data transmission speed
B.) A chunk of data with protocol-specific headers added at each OSI layer
A Protocol Data Unit (PDU) is the term used to describe the form that data takes at each layer of the OSI model. As data traverses down the layers on the sending node, each layer encapsulates the data by adding its specific headers (and sometimes footers), creating a PDU appropriate for that layer. This process ensures that data can be correctly processed, transmitted, and understood at each stage of its journey.
A PDU is not a device but a structured form of data as it is handled by network protocols.
A PDU refers to the format of data within network protocols, not a measure of speed.
A PDU pertains to the structure of data for protocol processing, not a method of encryption.
1.2.9
What is the primary purpose of data encapsulation in network protocols?
A.) To add additional data headers for routing and delivery
B.) To compress data for faster transmission
C.) To encrypt data for secure transmission
D.) To convert data into an analog signal for transmission
A.) To add additional data headers for routing and delivery
Data encapsulation is a fundamental process in network communication, where data at each layer of the OSI model is wrapped with protocol-specific headers (and sometimes footers). These headers provide essential information such as source and destination addresses, error checking, and more, which are necessary for the correct routing and delivery of data across a network. This process ensures that data packets are handled appropriately at each hop along their path to the destination.
Encapsulation is not about compressing data but organizing it for transmission. Compression is a separate process that might be applied to data before encapsulation.
Encapsulation itself does not involve encryption. Encryption may be applied to data as part of the security protocols at various layers but is distinct from the encapsulation process.
Encapsulation deals with the digital organization of data for transmission, not the conversion of digital signals to analog. The conversion to analog signals, if necessary, is handled at the Physical layer, separate from the encapsulation process.
1.2.9
An engineer uses a type of network adapter to connect a fiber link to a router. The transceiver fits into an optical interface on a layer 3 Ethernet router.
Of the choices, which layer 1 implementation does the engineer utilize?
A.) VoIP endpoint
B.) Media converter
C.) Bridge
D.) Switch
B.) Media converter
Media converters are layer 1 devices and are used to convert one cable type to another. These components alter the characteristics of one type of cable to match those of another.
A switch is a layer 2 device. Switches can handle traffic based on a node’s physical address which is also known as a Media Access Control (MAC) address.
A bridge is a layer 2 appliance or application that connects different networks as if they were one network.
A VoIP (Voice over Internet Protocol) endpoint is a phone system component that can be implemented as software running on a computer or smartphone, or as a dedicated traditional handset.
1.2.9
A communications engineer notices that every time it rains the signal becomes very degraded.
Which layer of the OSI model is the engineer most likely troubleshooting?
A.) Application
B.) Data Link
C.) Transport
D.) Physical
D.) Physical
The physical layer (PHY) of the OSI model (layer 1) is responsible for the transmission and receipt of the signals that represent bits of data from one node to another node. Wireless is one medium.
The data link layer (layer 2) is responsible for transferring data between nodes on the same logical segment.
At the transport layer on the sending host, the system packages data from the upper layers as a series of layer 4 protocol data units (PDUs), referred to as segments.
The application layer (layer 7) is at the top of the OSI stack. An application-layer protocol does not encapsulate any other protocols or provide services to any protocol.
1.2.9
Which of the following devices operate at the Data Link layer of the OSI model? (Select three.)
A.) Gateways
B.) Bridges
C.) Network interface cards (NICs)
D.) Hubs
E.) Repeaters
F.) Routers
G.) Switches
B.) Bridges
C.) Network interface cards (NICs)
G.) Switches
Network interface cards (NICs), bridges, and switches all operate at the OSI Data Link layer. They use the physical device address (MAC address) to identify packets.
Hubs and repeaters operate at the Physical layer. They simply repeat packets without regard to addresses.
Routers and gateways function at the Network layer. They examine the logical device and network address to perform routing tasks.
1.2.9
When the Data Link layer performs encapsulation, it adds control information to the payload in the form of header fields.
Which of the following are header fields added by the Data Link layer during encapsulation? (Select three.)
A.) Source hardware address
B.) Sequence number
C.) Checksum for basic error checking
D.) TTL (Time to Live)
E.) Window size
F.) Encryption type
G.) Destination hardware address
A.) Source hardware address
C.) Checksum for basic error checking
G.) Destination hardware address
The following are header fields added by the Data Link layer:
Source hardware address: The source hardware address, also known as the source MAC address, is added to the frame by the Data Link layer to indicate the origin of the frame on the network.
Destination hardware address: The destination hardware address, or destination MAC address, is included in the frame by the Data Link layer to ensure the frame reaches the correct device on the local network segment.
Checksum for basic error checking: A checksum is a form of basic error checking added to the frame by the Data Link layer. It helps to verify that the frame has been received intact and without corruption during transmission.
TTL is a field used at the Network layer within IP packets. It is used to limit the lifespan of a packet to prevent it from circulating indefinitely on the network. It is not added by the Data Link layer during encapsulation.
Sequence numbers are used at the Transport layer to keep track of the order of a series of packets or segments. They are not part of the Data Link layer encapsulation process.
Encryption types are related to the security protocols used to protect data during transmission, which are typically implemented at higher layers of the OSI model, such as the Presentation or Application layers, not at the Data Link layer.
Window size is a concept used in flow control at the Transport layer to manage the amount of data that can be sent without receiving an acknowledgment. It is not a header field added by the Data Link layer during encapsulation.
1.2.9
What is the role of an Access Control List (ACL) at Layer 3 (Network layer) of the OSI model?
A.) To act as a routing protocol for determining the best path for data packets
B.) To serve as a list of permissions for file access on the network
C.) To define the maximum size for packets transmitted across the network
D.) To filter network traffic by permitting or blocking packets based on IP addresses and other criteria
D.) To filter network traffic by permitting or blocking packets based on IP addresses and other criteria
At Layer 3, ACLs are used to enforce security policies by filtering traffic. They determine which packets are allowed to pass through a network device, such as a router, based on rules that include IP addresses, protocol types, ports, and other criteria.
ACLs do not define packet sizes; this is typically managed by the network protocols in use, such as TCP/IP.
ACLs are not routing protocols. Routing protocols like OSPF or BGP are used to determine the best path for data packets.
ACLs at Layer 3 do not manage file access permissions; they control network traffic. File access permissions are typically managed by the operating system or file system.
1.2.9
In the OSI model, what is the primary function of the Network layer?
A.) The primary function of the Network layer is to move data around an internetwork using logical network and host IDs.
B.) The primary function of the Network layer is to establish, manage, and terminate connections between applications on different hosts.
C.) The primary function of the Network layer is to ensure reliable transmission of data across a physical link.
D.) The primary function of the Network layer is to encode and convert data into signals suitable for transmission over the physical medium.
A.) The primary function of the Network layer is to move data around an internetwork using logical network and host IDs.
The primary function of the Network layer is to move data around an internetwork using logical network and host IDs. The Network layer, or Layer 3 of the OSI model, is responsible for the logical addressing of data and its delivery across different networks, or an internetwork. It uses logical addresses, such as IP addresses, to ensure data packets are routed to the correct destination network and ultimately to the correct host within that network. Routers, which operate at this layer, use the information contained in the packet’s network layer header to make forwarding decisions, guiding the packet through the internetwork hop by hop until it reaches its destination.
Encoding and converting data into signals suitable for transmission over the physical medium is the primary function of the Physical layer, or Layer 1 of the OSI model. Layer 1 is responsible for the transmission and reception of raw bit streams over a physical medium. It deals with the electrical, mechanical, procedural, and functional aspects of the physical connection between devices.
Establishing, managing, and terminating connections between applications on different hosts is the primary function of the Session layer, or Layer 5 of the OSI model. The Session layer is responsible for setting up, managing, and then tearing down sessions between presentation layer entities on different hosts. It provides mechanisms for controlling the dialogue between the two hosts, including synchronization and checkpointing.
Ensuring reliable transmission of data across a physical link is the primary function of the Transport layer, or Layer 4 of the OSI model. The Transport layer is responsible for providing reliable data transfer services to the upper layers. This includes the segmentation of data, acknowledgment of receipt, error correction through retransmission, and flow control.
1.2.9
Which of the following functions are performed by the OSI Transport layer? (Select three.)
A.) Path identification and selection
B.) Reliable message delivery
C.) Packet formatting for delivery through a medium
D.) Data segmentation and reassembly
E.) Consistent data formatting between dissimilar systems
F.) End-to-end flow control
G.) Media access control, logical topology, and device identification
B.) Reliable message delivery
D.) Data segmentation and reassembly
F.) End-to-end flow control
The Transport layer is responsible for breaking upper-layer data into segments and allowing reliable communication through end-to-end flow control, error detection, and error correction.
Message transmission through a medium is performed at the Physical layer.
Media access, logical topology, and device identification occur at the Data Link layer.
Path identification and selection is a function of the Network layer.
Data formatting is performed at the Presentation layer.
1.2.9
A security engineer configures software-based port security on a hardware firewall.
Which OSI model layer identifies the application ports to configure?
A.) Layer 3
B.) Layer 1
C.) Layer 2
D.) Layer 4
D.) Layer 4
The transport layer (layer 4) manages end-to-end communications. At layer 4, a port number identifies each application, such as 80 for hypertext transfer protocol (HTTP) web traffic.
Layer 1 (the physical layer) uses physical ports and cabling to connect and create a local area network.
Ethernet switching by using hardware-based media access control (MAC) addresses and wireless to wired bridging make use of physical layer adapters at layer 2.
At layer 3, the network layer, the routing part of the router (such as a SOHO router), makes forwarding decisions between the local private network and the public Internet.
1.2.9
What role does the Presentation layer (layer 6) of the OSI model play in terms of data compression and encryption?
A.) The Presentation layer is primarily responsible for the physical encryption of data using hardware-based methods.
B.) The Presentation layer handles the routing of data between different networks and supports encryption protocols like IPsec.
C.) The Presentation layer is involved in the logical organization of data into frames for transmission.
D.) The Presentation layer supports data compression and encryption to prepare data for network transmission.
D.) The Presentation layer supports data compression and encryption to prepare data for network transmission.
The Presentation layer transforms data to ensure that it is in the correct format for the application or network. This includes data compression to reduce the size of the data for transmission and encryption to secure the data during transfer.
The Presentation layer deals with data transformation and representation, not physical encryption methods, which are typically implemented at lower layers or by specific security hardware.
The logical organization of data into frames is a function of the Data Link layer (layer 2) of the OSI model.
Routing is a function of the Network layer (layer 3), and while the Presentation layer can be involved in encryption, IPsec is a protocol that operates at the Network layer, not the Presentation layer.
1.2.9
Which of the following statements accurately describes the function of the Session layer (layer 5) in the OSI model?
A.) The Session layer is used for character set conversion, such as between ASCII and Unicode.
B.) The Session layer administers the process of establishing, managing, and terminating a dialog between client and server.
C.) The Session layer is responsible for routing packets across different networks.
D.) The Session layer provides the physical transmission of data over network media.
B.) The Session layer administers the process of establishing, managing, and terminating a dialog between client and server.
The correct answer is that the Session layer administers the process of establishing, managing, and terminating a dialog between client and server. The Session layer is crucial for controlling the dialog between two computers or network devices. It establishes, manages, and terminates connections, ensuring that data is properly synchronized and organized during communication sessions.
The Session layer is responsible for routing packets across different networks is incorrect because routing is a function of the Network layer (layer 3) of the OSI model, not the Session layer.
The Session layer provides the physical transmission of data over network media is incorrect because the physical transmission of data is the responsibility of the Physical layer (layer 1) of the OSI model.
The Session layer is used for character set conversion, such as between ASCII and Unicode is incorrect because character set conversion is a function of the Presentation layer (layer 6), which is responsible for data representation and encoding, not the Session layer.
1.2.9
Match each networking function or device on the left with its associated OSI model layer on the right.
Open Systems Interconnection (OSI) Model Layers:
A.) Presentation layer
B.) Session layer
C.) Transport layer
D.) Network layer
E.) Data Link layer
F.) Application layer
Network or device function:
A.) HTTP
B.) Translates data
C.) Session ID number
D.) Port number
E.) Router
F.) Switch
F.) Application layer goes with A.) HTTP
A.) Presentation layer goes with B.) Translates data
B.) Session layer goes with C.) Session ID number
C.) Transport layer goes with D.) Port number
D.) Network layer goes with E.) Router
E.) Data Link layer goes with F.) Switch
The following describes how devices function at different layers of the OSI model:
HTTP functions at the Application layer.
Encapsulation happens at the Presentation layer.
Session IDs are assigned at the Session layer.
Port numbers are assigned at the Transport layer.
Routers function at the Network layer.
Switches function at the Data Link layer.
1.2.9
A network engineer is designing a network in various offices to create multiple broadcast domains. Each has its own Virtual Local Area Network (VLAN).
When configuring these multiple broadcast domains on the switch, the switch will be operating at what layer of the OSI model?
A.) Layer 4 (Transport Layer)
B.) Layer 7 (Application Layer)
C.) Layer 1 (Physical Layer)
D.) Layer 2 (Data Link Layer)
Layer 2 (Data Link Layer)
Layer 2 (Datalink Layer) is the correct answer. VLANs (Virtual Local Area Networks) are a Layer 2 technology. When configuring VLANs on a switch, the network engineer is working at the Data Link Layer. This layer is responsible for segmenting the network into multiple broadcast domains using VLAN IDs. Devices like switches and bridges operate at this layer to manage MAC addresses and frames, which are essential for VLAN functionality.
The Physical Layer is responsible for the physical connection between devices, including cables, transceivers, and media converters. It deals with the transmission and reception of raw bit streams over a physical medium. Configuring VLANs, which involves creating multiple broadcast domains, is not a function of the Physical Layer.
The Transport Layer is responsible for end-to-end communication and error recovery. It deals with the segmentation and reassembly of data, as well as flow control and error correction. Configuring VLANs, which involves creating multiple broadcast domains, is not a function of the Transport Layer.
The Application Layer is the topmost layer of the OSI model and is responsible for providing network services directly to end-users and applications. It deals with protocols like HTTP, FTP, and SMTP. Configuring VLANs, which involves creating multiple broadcast domains, is not a function of the Application Layer.
1.3.11
A freelance photographer is setting up a home office. They need to connect a desktop, a laptop, a network printer, and occasionally, guests’ devices to the Internet and to each other for file sharing and printing.
Which type of network is MOST suitable for this scenario?
answer
A.) CAN (Campus Area Network)
B.) SOHO (Small Office/Home Office) Network
C.) PAN (Personal Area Network)
D.) MAN (Metropolitan Area Network)
B.) SOHO (Small Office/Home Office) Network
A SOHO (Small Office/Home Office) network is the correct answer because SOHO networks are specifically designed for small office or home office environments where a small number of computing hosts need to be interconnected. They typically rely on a single integrated appliance (like a SOHO router) for local and Internet connectivity, making it perfect for the photographer’s needs.
PANs are designed for personal use within a very limited area, connecting devices like phones, laptops, and wearable devices to a single person’s devices. While it could support some of the photographer’s needs, it is not ideal for connecting multiple types of devices like printers and guests’ devices efficiently.
MANs are intended to cover larger geographic areas than LANs, typically a city or large campus. This scenario describes a need for a network within a single home office, which is much smaller in scale than what MANs are designed for.
CANs are used to connect networks in a limited geographical area, such as a university campus, school, or corporate facility. The scenario involves a much smaller scale network, suitable for a single home office, making a CAN overly complex and extensive for the photographer’s needs.
1.3.11
Which of the following interfaces does a SOHO router provide at the Physical Layer of the OSI model? (Select three.)
answer
A.) WAN port for Internet Service Provider (ISP) connection
B.) VGA ports for video output
C.) USB ports for direct computer connection
D.) HDMI ports for multimedia streaming
E.) RJ-45 ports for a local cabled network
F.) Radio antennas for wireless signal transmission
G.) SATA ports for internal storage connection
A.) WAN port for Internet Service Provider (ISP) connection
E.) RJ-45 ports for a local cabled network
F.) Radio antennas for wireless signal transmission
The following are the correct answers for the interfaces that a SOHO router provides at the Physical Layer:
RJ-45 ports are typically provided on a SOHO router to implement a local cabled network, usually labeled as LAN ports. These ports are essential for wired connections within the network.
Radio antennas are a crucial part of a SOHO router, enabling it to transmit and receive wireless signals. This allows devices like PCs, tablets, smartphones, and printers to connect to the network without physical cables.
The WAN port on a SOHO router is designed to connect to the Internet Service Provider’s (ISP’s) network, facilitating internet access. This port can vary in type, including RJ-45 for fiber connections, RJ-11 for DSL services, or a coaxial F-connector for cable services, depending on the router model and the type of internet service used.
Although some routers may feature USB ports for connecting devices such as printers or for network storage, they are not used for the primary function of implementing a local cabled network or connecting to an ISP’s network at the Physical Layer.
HDMI ports are used for transmitting high-definition video and audio signals from one device to another and are not used in SOHO routers for network connectivity or internet access.
SATA ports are used for connecting internal storage devices like hard drives and SSDs within computers and are not typically found on SOHO routers, as they do not serve a networking or internet connectivity function at the Physical Layer.
VGA ports are used for video output to monitors and projectors and do not serve a purpose in the networking capabilities of a SOHO router at the Physical Layer.
1.3.11
Which of the following functions does a SOHO router implement at layer 2 to make use of its Physical layer adapters? (Select two.)
answer
A.) Network Address Translation (NAT)
B.) Ethernet switch
C.) Firewall
D.) DHCP server
E.) Wireless access point
B.) Ethernet switch
E.) Wireless access point
The following are the functions that a SOHO router implements:
Ethernet switch. The RJ-45 jacks on a SOHO router are connected internally by an Ethernet switch, allowing multiple wired devices to communicate within the same network segment. This is a key function at layer 2, facilitating the use of Physical layer adapters for wired connections.
Wireless access point. A SOHO router includes a wireless access point, which uses radio antennas to implement a version of the Wi-Fi standard. This allows wireless devices such as PCs, tablets, smartphones, and printers to form a network. The access point is also connected to the Ethernet switch internally, bridging the wired and wireless segments into a single logical data link network.
While a DHCP server is a common feature in SOHO routers, it operates at a higher layer (Layer 3 - Network Layer) by assigning IP addresses to devices on the network. It is not a function implemented at Layer 2, which deals with physical addressing and access to the media.
A firewall is a network security device that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Firewalls operate at Layer 3 (Network Layer) and above, making decisions based on IP addresses and other higher-layer protocols, not at Layer 2.
NAT is a method used to remap one IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic routing device. This function is performed at the Network Layer (Layer 3), not at the Data Link Layer (Layer 2), as it involves the manipulation of IP addresses.
1.3.11
A small office/home office (SOHO) network is configured to use the private IP address range of 192.168.1.0/24.
If you are setting up a SOHO router for this network, which of the following IP addresses would be the MOST appropriate for the router?
answer
A.) 203.0.113.1
B.) 192.168.2.1
C.) 192.168.1.255
D.) 192.168.1.1
D.) 192.168.1.1
192.168.1.1 is the correct answer. This IP address is within the specified private IP address range of 192.168.1.0/24 and is commonly used as the default gateway address for devices on the network. It is a suitable choice for the router’s IP address, allowing it to manage traffic between the local network and the Internet.
The 192.168.2.1 IP address is not within the specified private IP address range of 192.168.1.0/24. It belongs to a different subnet (192.168.2.0/24), which means it cannot be used for a router within the 192.168.1.0/24 network.
The 192.168.1.255 IP address is the broadcast address for the 192.168.1.0/24 network. It is reserved for broadcasting messages to all hosts within the network and cannot be assigned to any single device, including the router.
The 203.0.113.1 IP address is a public IP address and would not be used for a router within a private network using the 192.168.1.0/24 range. Public IP addresses are used on the WAN (Wide Area Network) side of a router for communication over the Internet, not for internal network addressing.
1.3.11
What is the MOST effective method for protecting the management interface of a SOHO router?
answer
A.) Setting the router to automatically accept firmware updates
B.) Configuring a strong administrative account passphrase
C.) Enabling UPnP (Universal Plug and Play)
D.) Disabling the firewall
B.) Configuring a strong administrative account passphrase
Configuring a strong administrative account passphrase is a critical security measure for protecting the router’s management interface. A strong passphrase helps prevent unauthorized access to the router’s settings, where malicious changes could compromise the entire network’s security.
Enabling UPnP (Universal Plug and Play) is a convenience feature that allows devices to automatically discover and communicate with each other on a network. While it can simplify network setup and device interaction, it does not provide protection for the router’s management interface.
Disabling the firewall would decrease the network’s security rather than protect the management interface. The firewall is an essential feature that helps block unauthorized access and potential attacks from the Internet.
Setting the router to automatically accept firmware updates, while generally a good practice for ensuring the router is up-to-date with the latest security patches, does not directly protect the management interface. Unauthorized individuals could still attempt to access the interface if the administrative passphrase is weak or compromised.
1.3.11
At layer 4 of the OSI model, how is each application identified to facilitate proper routing and delivery of data?
answer
A.) Through the application’s unique username and password
B.) Through the use of encryption algorithms
C.) By a unique port number assigned to the application
D.) By the MAC address of the destination device
D.) By a unique port number assigned to the application
At layer 4, the Transport Layer, each application is identified by a unique port number. This port number is used to ensure that data is delivered to the correct application on a device. For example, web traffic typically uses port 80 for HTTP or port 443 for HTTPS, and email might use port 25 for SMTP. This system allows multiple applications to run on a single device without their data streams getting mixed up.
MAC addresses are used at layer 2 (Data Link Layer) of the OSI model to identify devices on the same local network. Layer 4, the Transport Layer, does not use MAC addresses for identifying applications.
Encryption algorithms are used to secure data in transit rather than to identify applications. While encryption is crucial for security, it does not play a role in the identification or routing of applications at layer 4.
An application’s unique username and password are used for authentication purposes, not for identifying applications at the Transport Layer. Usernames and passwords ensure that only authorized users can access an application, but they do not play a role in the routing or delivery of data at layer 4.
1.3.11
Which of the following BEST describes a demarcation point in the context of telecommunications?
answer
A.) The central hub where all ISPs connect and exchange data
B.) The protocol used for encrypting data over the Internet
C.) The maximum data transfer rate achievable by the ISP
D.) The point at which the telco’s cabling enters the customer premises
D.) The point at which the telco’s cabling enters the customer premises
The demarcation point (often shortened to “demarc”) is the point where the telecommunications company’s (telco’s) responsibility ends and the customer’s responsibility begins; typically where the telco’s cabling enters the building or premises.
The maximum data transfer rate achievable by the ISP refers to the bandwidth or speed of an internet connection provided by an ISP, not to the physical or logical point of demarcation between the ISP’s network and the customer’s premises.
The central hub where all ISPs connect and exchange data resembles an Internet Exchange Point (IXP), where ISPs interconnect and exchange internet traffic. The demarcation point, however, is specific to the boundary between the telecommunications provider’s network and the customer’s network.
The protocol used for encrypting data over the internet refers to encryption protocols, such as SSL/TLS, used for securing data transmitted over the Internet. It has no relation to the concept of a demarcation point, which is about the physical boundary and responsibility between a telco’s network and the customer’s premises.
1.3.11
What do Internet Service Providers (ISPs) use to establish links between their networks within an Internet eXchange Point (IXP) data center?
answer
A.) Peer-to-peer file sharing
B.) Bluetooth connectivity
C.) Transit and peering arrangements
D.) NFC (Near Field Communication)
C.) Transit and peering arrangements
Within an Internet eXchange Point (IXP) data center, ISPs establish links between their networks using transit and peering arrangements. These arrangements allow them to carry traffic to and from parts of the Internet they do not physically own, facilitating the exchange of internet traffic between different ISPs’ networks.
Peer-to-peer file sharing is a method of distributing or accessing digital media using a peer-to-peer networking technology. It is not used by ISPs to establish links between their networks. ISPs require more formal and scalable arrangements to exchange traffic.
Bluetooth is a wireless technology standard for exchanging data over short distances. It is primarily used for connecting personal devices and is not suitable or used for establishing links between ISPs’ networks within an IXP data center.
NFC is a set of communication protocols for communication between two electronic devices over a distance of 4 cm or less. It is commonly used for contactless payment systems and simple data exchange between devices. NFC is not used by ISPs to establish links between their networks at IXPs.
1.3.11
What is the decimal form of the following binary IP address?
11001101.00111001.10101001.01000010
answer
A.) 206.58.170.67
B.) 190.42.154.51
C.) 205.57.169.66
D.) 238.90.202.99
C.) 205.57.169.66
The decimal equivalent of the 11001101.00111001.10101001.01000010 IP address is 205.57.169.66. To convert from binary to decimal, use the decimal equivalent of the following binary numbers:
10000000: 128
01000000: 64
00100000: 32
00010000: 16
00001000: 8
00000100: 4
00000010: 2
00000001: 1
To find the decimal form of a binary number, add up each decimal equivalent for each 1 bit in the address. For example, the equation for the number 11001101 is 128 + 64 + 8 + 4 + 1 = 205.
1.3.11
Which of the following sets correctly represents the possible values that can be represented by each digit in hexadecimal notation?
answer
A.) 0 through 7
B.) 1 through 10
C.) 0 through 9 and A through E
D.) 0 through 9 and A through F
