Podcast
Questions and Answers
What is the main function of a WAN?
What is the main function of a WAN?
Who typically owns a WAN?
Who typically owns a WAN?
What is a disadvantage of the hub-and-spoke WAN topology?
What is a disadvantage of the hub-and-spoke WAN topology?
Which WAN topology allows direct communication between any two sites?
Which WAN topology allows direct communication between any two sites?
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Why are WANs considered necessary for businesses?
Why are WANs considered necessary for businesses?
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Which statement is true about a dual-homed topology?
Which statement is true about a dual-homed topology?
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What kind of connection is typical for a point-to-point WAN topology?
What kind of connection is typical for a point-to-point WAN topology?
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What is a potential issue with implementing a full mesh topology?
What is a potential issue with implementing a full mesh topology?
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What is the main function of a CSU in a digital-leased line environment?
What is the main function of a CSU in a digital-leased line environment?
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Which technology is an example of circuit switching?
Which technology is an example of circuit switching?
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What characterizes packet switching compared to circuit switching?
What characterizes packet switching compared to circuit switching?
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What does a DSU do in the context of WAN operations?
What does a DSU do in the context of WAN operations?
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Which of the following best describes a connectionless system in packet switching?
Which of the following best describes a connectionless system in packet switching?
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What is the primary role of a core router in a WAN?
What is the primary role of a core router in a WAN?
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Which of the following statements about latency and jitter is correct in the context of packet switching?
Which of the following statements about latency and jitter is correct in the context of packet switching?
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What type of network requires a dedicated circuit to be established before communication can start?
What type of network requires a dedicated circuit to be established before communication can start?
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Which of the following describes the primary focus of WAN operations in the OSI Model?
Which of the following describes the primary focus of WAN operations in the OSI Model?
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What is the role of Customer Premises Equipment (CPE) in a WAN?
What is the role of Customer Premises Equipment (CPE) in a WAN?
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How does a small office like SPAN Engineering connect to the Internet?
How does a small office like SPAN Engineering connect to the Internet?
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What is a significant characteristic of a Distributed Network?
What is a significant characteristic of a Distributed Network?
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Which device is specifically responsible for modulating digital signals to voice frequencies in legacy WAN technology?
Which device is specifically responsible for modulating digital signals to voice frequencies in legacy WAN technology?
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What method has SPAN Engineering used to connect remote branch offices to their data center?
What method has SPAN Engineering used to connect remote branch offices to their data center?
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Which term describes the actual copper or fiber cable connecting the CPE to the Central Office?
Which term describes the actual copper or fiber cable connecting the CPE to the Central Office?
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What distinguishes a WAN from a LAN regarding service provider dependency?
What distinguishes a WAN from a LAN regarding service provider dependency?
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Which layer focuses on the flow control and encapsulation aspects of WAN operations?
Which layer focuses on the flow control and encapsulation aspects of WAN operations?
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In the context of SPAN Engineering, what is the significance of employing an in-house IT staff?
In the context of SPAN Engineering, what is the significance of employing an in-house IT staff?
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What is the purpose of WAN access standards established by organizations like TIA/EIA and IEEE?
What is the purpose of WAN access standards established by organizations like TIA/EIA and IEEE?
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What describes the Central Office (CO) in a WAN environment?
What describes the Central Office (CO) in a WAN environment?
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What significant change occurred in SPAN Engineering's setup six years after its founding?
What significant change occurred in SPAN Engineering's setup six years after its founding?
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How does a Broadband modem differ from a Dialup modem?
How does a Broadband modem differ from a Dialup modem?
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A CSU provides termination for the digital signal and ensures connection integrity through error correction.
A CSU provides termination for the digital signal and ensures connection integrity through error correction.
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Packet switching requires a dedicated circuit to be established before communication can start.
Packet switching requires a dedicated circuit to be established before communication can start.
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The Integrated Services Digital Network (ISDN) is an example of packet-switched technology.
The Integrated Services Digital Network (ISDN) is an example of packet-switched technology.
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In a connectionless packet-switched system, full addressing information must be carried in each packet.
In a connectionless packet-switched system, full addressing information must be carried in each packet.
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Communication can start immediately in a circuit-switched network without any setup time.
Communication can start immediately in a circuit-switched network without any setup time.
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Both circuit switching and packet switching can be used to transmit voice or data over a WAN.
Both circuit switching and packet switching can be used to transmit voice or data over a WAN.
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The Internet is an example of a connection-oriented packet-switched system.
The Internet is an example of a connection-oriented packet-switched system.
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Latency and jitter are generally lower in packet-switching networks compared to circuit-switched networks.
Latency and jitter are generally lower in packet-switching networks compared to circuit-switched networks.
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A WAN operates within the geographic scope of a LAN.
A WAN operates within the geographic scope of a LAN.
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Organizations must pay a fee to use WAN services provided by service providers.
Organizations must pay a fee to use WAN services provided by service providers.
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In a full mesh topology, all communication must go through a central hub.
In a full mesh topology, all communication must go through a central hub.
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Hub-and-Spoke topology is advantageous because it eliminates the need for virtual circuits.
Hub-and-Spoke topology is advantageous because it eliminates the need for virtual circuits.
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A point-to-point topology employs a dedicated leased-line connection between two endpoints.
A point-to-point topology employs a dedicated leased-line connection between two endpoints.
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Dual-homed topology offers redundancy and load balancing but is less expensive to implement than single-homed topologies.
Dual-homed topology offers redundancy and load balancing but is less expensive to implement than single-homed topologies.
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Without WANs, LANs would become interconnected networks.
Without WANs, LANs would become interconnected networks.
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Consumers can communicate over the Internet with service providers thanks to WANs.
Consumers can communicate over the Internet with service providers thanks to WANs.
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WANs require additional networking hardware such as routers and switches.
WANs require additional networking hardware such as routers and switches.
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SPAN Engineering initially started as a large international corporation.
SPAN Engineering initially started as a large international corporation.
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The cost of the network is a minor expense for SPAN Engineering as it grows.
The cost of the network is a minor expense for SPAN Engineering as it grows.
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A WAN allows branch offices to connect to central data centers.
A WAN allows branch offices to connect to central data centers.
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Local loop refers to the long-haul fiber-optic communications lines in a WAN.
Local loop refers to the long-haul fiber-optic communications lines in a WAN.
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Data Terminal Equipment (DTE) connects to the local loop through Data Communications Equipment (DCE).
Data Terminal Equipment (DTE) connects to the local loop through Data Communications Equipment (DCE).
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The main role of the Central Office (CO) is to house customer devices.
The main role of the Central Office (CO) is to house customer devices.
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SPAN Engineering has only a single office after 20 years in business.
SPAN Engineering has only a single office after 20 years in business.
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Access servers are modern technology used to integrate Internet services in WANs.
Access servers are modern technology used to integrate Internet services in WANs.
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WAN operations focus primarily on the physical layer and the application layer of the OSI Model.
WAN operations focus primarily on the physical layer and the application layer of the OSI Model.
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To create a WAN, companies must usually subscribe to an outside WAN service provider.
To create a WAN, companies must usually subscribe to an outside WAN service provider.
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SPAN Engineering has used DSL to connect its initial small office to the Internet.
SPAN Engineering has used DSL to connect its initial small office to the Internet.
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Dialup modems are currently the most widely used technology for WAN connections.
Dialup modems are currently the most widely used technology for WAN connections.
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Private dedicated lines are utilized by nearby branch offices of SPAN Engineering.
Private dedicated lines are utilized by nearby branch offices of SPAN Engineering.
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A WAN operates beyond the geographic scope of a ______.
A WAN operates beyond the geographic scope of a ______.
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Without WANs, LANs would be a series of isolated ______.
Without WANs, LANs would be a series of isolated ______.
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The ______-and-Spoke topology features a single hub that manages connections to multiple spoke sites.
The ______-and-Spoke topology features a single hub that manages connections to multiple spoke sites.
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In a Full Mesh topology, any site can communicate directly with ______ other site.
In a Full Mesh topology, any site can communicate directly with ______ other site.
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A disadvantage of the hub-and-spoke topology is that all communication has to go through the ______.
A disadvantage of the hub-and-spoke topology is that all communication has to go through the ______.
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Organizations must pay a fee to use the ______ services provided by service providers.
Organizations must pay a fee to use the ______ services provided by service providers.
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A ______-homed topology provides redundancy and load balancing but is more expensive to implement.
A ______-homed topology provides redundancy and load balancing but is more expensive to implement.
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WANs are necessary for businesses to communicate between geographically separated ______.
WANs are necessary for businesses to communicate between geographically separated ______.
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A dedicated circuit must be established for communication in a ______ network.
A dedicated circuit must be established for communication in a ______ network.
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The ______ is responsible for converting line frames into frames that can be interpreted by the LAN.
The ______ is responsible for converting line frames into frames that can be interpreted by the LAN.
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Packet switching allows multiple pairs of nodes to communicate over the same ______.
Packet switching allows multiple pairs of nodes to communicate over the same ______.
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The two common types of circuit-switched WAN technologies are PSTN and ______.
The two common types of circuit-switched WAN technologies are PSTN and ______.
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A ______ router resides within the middle or backbone of the WAN.
A ______ router resides within the middle or backbone of the WAN.
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In a connectionless system, each packet must carry full ______ information.
In a connectionless system, each packet must carry full ______ information.
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The CSU in a digital-leased line environment ensures connection ______ through error correction.
The CSU in a digital-leased line environment ensures connection ______ through error correction.
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Many pairs of nodes can communicate over the same channel in a ______ network.
Many pairs of nodes can communicate over the same channel in a ______ network.
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WANs require additional networking hardware including routers and ______.
WANs require additional networking hardware including routers and ______.
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As SPAN Engineering grew, the company was required to implement a ______ to connect remote sites to the central data center.
As SPAN Engineering grew, the company was required to implement a ______ to connect remote sites to the central data center.
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In its early days, SPAN Engineering connected to the Internet using ______.
In its early days, SPAN Engineering connected to the Internet using ______.
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SPAN Engineering's network has grown to several subnetworks spanning several ______ of the building.
SPAN Engineering's network has grown to several subnetworks spanning several ______ of the building.
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To justify large expenses on network infrastructure, companies expect optimal network ______.
To justify large expenses on network infrastructure, companies expect optimal network ______.
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The cost of the network is a significant ______ for SPAN Engineering as it grows.
The cost of the network is a significant ______ for SPAN Engineering as it grows.
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WAN operations focus primarily on the physical and ______ layer of the OSI Model.
WAN operations focus primarily on the physical and ______ layer of the OSI Model.
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Customer Premises Equipment (CPE) consists of devices located on the ______ edge connecting to a carrier.
Customer Premises Equipment (CPE) consists of devices located on the ______ edge connecting to a carrier.
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The ______ point is established to separate customer equipment from service provider equipment.
The ______ point is established to separate customer equipment from service provider equipment.
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SPAN Engineering, after 20 years, has grown to thousands of employees distributed in offices around the ______.
SPAN Engineering, after 20 years, has grown to thousands of employees distributed in offices around the ______.
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Data Terminal Equipment (DTE) connects to the local loop through the ______.
Data Terminal Equipment (DTE) connects to the local loop through the ______.
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SPAN Engineering experienced rapid growth after being contracted to implement a full-sized waste conversion ______.
SPAN Engineering experienced rapid growth after being contracted to implement a full-sized waste conversion ______.
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The Central Office (CO) connects the CPE to the ______ network.
The Central Office (CO) connects the CPE to the ______ network.
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Layer 1 protocols describe how to provide electrical, mechanical, ______, and functional connects to communication service.
Layer 1 protocols describe how to provide electrical, mechanical, ______, and functional connects to communication service.
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Match the following WAN devices with their primary functions:
Match the following WAN devices with their primary functions:
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Match the following types of network technologies with their characteristics:
Match the following types of network technologies with their characteristics:
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Match the following circuit-switched technologies with their examples:
Match the following circuit-switched technologies with their examples:
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Match the following WAN topologies with their descriptions:
Match the following WAN topologies with their descriptions:
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Match the purpose of WANs with their benefits:
Match the purpose of WANs with their benefits:
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Match the following terms with their definitions:
Match the following terms with their definitions:
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Match the WAN topology with its main characteristic:
Match the WAN topology with its main characteristic:
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Match the following features with the types of switching technology:
Match the following features with the types of switching technology:
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Match the reason for WAN necessity with its explanation:
Match the reason for WAN necessity with its explanation:
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Match the following WAN strategies with their benefits:
Match the following WAN strategies with their benefits:
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Match the WAN topology with its disadvantage:
Match the WAN topology with its disadvantage:
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Match the following WAN concepts with their descriptions:
Match the following WAN concepts with their descriptions:
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Match the WAN topology type with its typical usage:
Match the WAN topology type with its typical usage:
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Match the following WAN characteristics with their impacts:
Match the following WAN characteristics with their impacts:
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Match the following terms with their definitions:
Match the following terms with their definitions:
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Match the benefit of WANs with the specific outcome:
Match the benefit of WANs with the specific outcome:
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Match the following WAN terminology with their descriptions:
Match the following WAN terminology with their descriptions:
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Match the following SPAN Engineering stages with their descriptions:
Match the following SPAN Engineering stages with their descriptions:
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Match the following WAN operations with their OSI model layers:
Match the following WAN operations with their OSI model layers:
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Match the following WAN devices with their functions:
Match the following WAN devices with their functions:
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Match the following WAN connection methods with their usage:
Match the following WAN connection methods with their usage:
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Match the following changes in SPAN Engineering with their timeline:
Match the following changes in SPAN Engineering with their timeline:
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Match the following WAN characteristics with their definitions:
Match the following WAN characteristics with their definitions:
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Match the following common WAN organizations with their focus:
Match the following common WAN organizations with their focus:
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Match the following WAN-related terms with their meanings:
Match the following WAN-related terms with their meanings:
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Match the following WAN components with their descriptions:
Match the following WAN components with their descriptions:
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Match the following network configurations with their characteristics:
Match the following network configurations with their characteristics:
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Match the following WAN principles with their details:
Match the following WAN principles with their details:
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Study Notes
Purpose of WANs
- WANs connect LANs over larger geographic distances, interlinking enterprises with remote locations and branch offices.
- Service providers own WANs, unlike LANs, which are typically organization-owned. Fees are incurred for WAN services.
- WANs facilitate communication for remote sites, enabling data, voice, and video transport.
Necessity of WANs
- Without WANs, LANs remain isolated, hindering communication between distant sites.
- Businesses require inter-office communication for sharing data, especially for regional and branch offices.
- Increased connectivity needs arise from mobile employees and consumer interactions with online services.
WAN Topologies
- Various topologies are utilized to interconnect sites via WANs. Key examples include:
- Point-to-Point: Direct, dedicated connections like T1/E1 lines between two endpoints.
- Hub-and-Spoke: Central hub connects multiple spoke sites, facilitating shared access.
- Full Mesh: Allows direct communication between all sites but requires more virtual circuits.
- Dual-homed: Offers redundancy and load balancing, though more expensive and complex to set up.
Evolving Networks
- Companies focus on optimizing network efficiency to boost profitability during economic downturns.
- Networks must adapt as companies expand, illustrated by SPAN Engineering’s growth from local to global scale.
Small Office Setup
- SPAN Engineering has 15 employees, utilizing a single LAN for VoIP, peripheral sharing, and internet access via DSL.
Campus Network Expansion
- After five years, SPAN expands infrastructure, transitioning to several subnetworks within a multi-floor office building.
Branch Networking
- As SPAN opens branch offices, a WAN is implemented to enable remote access to the central data center.
- Local branches use dedicated lines, while international branches rely on the Internet for connectivity.
Distributed Network Maturity
- SPAN Engineering reaches a global presence with thousands of employees, requiring sophisticated network services for efficiency and cost reduction.
WAN Operations and OSI Model
- WANs operate mainly at the OSI Model's Physical and Data Link layers, focusing on physical addressing and flow control.
- Various authorities set standards for WAN access including TIA/EIA, ISO, and IEEE.
Common WAN Terminology
- Customer Premises Equipment (CPE): Devices at the enterprise edge that connect to a carrier.
- Data Communications Equipment (DCE): Interfaces connecting customers to the WAN.
- Data Terminal Equipment (DTE): Devices sending data for WAN transmission.
- Demarcation Point: Divides customer and service provider equipment.
- Local Loop: Connects CPE to Central Office (CO).
- Central Office (CO): Service provider facility connecting to the network.
WAN Devices
- Dialup modem: Converts digital signals for public telephone networks.
- Access server: Manages dial-up communications.
- Broadband modem: Used with high-speed Internet connections, operating at higher frequencies.
- CSU/DSU: Ensures digital signal integrity and compatibility with LAN frames.
- Router: Connects networks and allows WAN access.
- Core router/Multilayer switch: Operates within the WAN backbone.
Circuit Switching
- Establishes dedicated channels between nodes before communication begins.
- Examples include PSTN and ISDN, with communication requiring completed connections prior to data exchange.
Packet Switching
- Splits data into packets routed over shared networks without pre-established circuits.
- Connectionless systems (e.g., Internet) carry full addressing in each packet, while connection-oriented systems (e.g., Frame Relay) utilize route identifiers.
- Packet switching tends to be cheaper than circuit switching but faces higher latency and jitter.
Purpose of WANs
- WANs connect LANs over larger geographic distances, interlinking enterprises with remote locations and branch offices.
- Service providers own WANs, unlike LANs, which are typically organization-owned. Fees are incurred for WAN services.
- WANs facilitate communication for remote sites, enabling data, voice, and video transport.
Necessity of WANs
- Without WANs, LANs remain isolated, hindering communication between distant sites.
- Businesses require inter-office communication for sharing data, especially for regional and branch offices.
- Increased connectivity needs arise from mobile employees and consumer interactions with online services.
WAN Topologies
- Various topologies are utilized to interconnect sites via WANs. Key examples include:
- Point-to-Point: Direct, dedicated connections like T1/E1 lines between two endpoints.
- Hub-and-Spoke: Central hub connects multiple spoke sites, facilitating shared access.
- Full Mesh: Allows direct communication between all sites but requires more virtual circuits.
- Dual-homed: Offers redundancy and load balancing, though more expensive and complex to set up.
Evolving Networks
- Companies focus on optimizing network efficiency to boost profitability during economic downturns.
- Networks must adapt as companies expand, illustrated by SPAN Engineering’s growth from local to global scale.
Small Office Setup
- SPAN Engineering has 15 employees, utilizing a single LAN for VoIP, peripheral sharing, and internet access via DSL.
Campus Network Expansion
- After five years, SPAN expands infrastructure, transitioning to several subnetworks within a multi-floor office building.
Branch Networking
- As SPAN opens branch offices, a WAN is implemented to enable remote access to the central data center.
- Local branches use dedicated lines, while international branches rely on the Internet for connectivity.
Distributed Network Maturity
- SPAN Engineering reaches a global presence with thousands of employees, requiring sophisticated network services for efficiency and cost reduction.
WAN Operations and OSI Model
- WANs operate mainly at the OSI Model's Physical and Data Link layers, focusing on physical addressing and flow control.
- Various authorities set standards for WAN access including TIA/EIA, ISO, and IEEE.
Common WAN Terminology
- Customer Premises Equipment (CPE): Devices at the enterprise edge that connect to a carrier.
- Data Communications Equipment (DCE): Interfaces connecting customers to the WAN.
- Data Terminal Equipment (DTE): Devices sending data for WAN transmission.
- Demarcation Point: Divides customer and service provider equipment.
- Local Loop: Connects CPE to Central Office (CO).
- Central Office (CO): Service provider facility connecting to the network.
WAN Devices
- Dialup modem: Converts digital signals for public telephone networks.
- Access server: Manages dial-up communications.
- Broadband modem: Used with high-speed Internet connections, operating at higher frequencies.
- CSU/DSU: Ensures digital signal integrity and compatibility with LAN frames.
- Router: Connects networks and allows WAN access.
- Core router/Multilayer switch: Operates within the WAN backbone.
Circuit Switching
- Establishes dedicated channels between nodes before communication begins.
- Examples include PSTN and ISDN, with communication requiring completed connections prior to data exchange.
Packet Switching
- Splits data into packets routed over shared networks without pre-established circuits.
- Connectionless systems (e.g., Internet) carry full addressing in each packet, while connection-oriented systems (e.g., Frame Relay) utilize route identifiers.
- Packet switching tends to be cheaper than circuit switching but faces higher latency and jitter.
Purpose of WANs
- WANs connect LANs over larger geographic distances, interlinking enterprises with remote locations and branch offices.
- Service providers own WANs, unlike LANs, which are typically organization-owned. Fees are incurred for WAN services.
- WANs facilitate communication for remote sites, enabling data, voice, and video transport.
Necessity of WANs
- Without WANs, LANs remain isolated, hindering communication between distant sites.
- Businesses require inter-office communication for sharing data, especially for regional and branch offices.
- Increased connectivity needs arise from mobile employees and consumer interactions with online services.
WAN Topologies
- Various topologies are utilized to interconnect sites via WANs. Key examples include:
- Point-to-Point: Direct, dedicated connections like T1/E1 lines between two endpoints.
- Hub-and-Spoke: Central hub connects multiple spoke sites, facilitating shared access.
- Full Mesh: Allows direct communication between all sites but requires more virtual circuits.
- Dual-homed: Offers redundancy and load balancing, though more expensive and complex to set up.
Evolving Networks
- Companies focus on optimizing network efficiency to boost profitability during economic downturns.
- Networks must adapt as companies expand, illustrated by SPAN Engineering’s growth from local to global scale.
Small Office Setup
- SPAN Engineering has 15 employees, utilizing a single LAN for VoIP, peripheral sharing, and internet access via DSL.
Campus Network Expansion
- After five years, SPAN expands infrastructure, transitioning to several subnetworks within a multi-floor office building.
Branch Networking
- As SPAN opens branch offices, a WAN is implemented to enable remote access to the central data center.
- Local branches use dedicated lines, while international branches rely on the Internet for connectivity.
Distributed Network Maturity
- SPAN Engineering reaches a global presence with thousands of employees, requiring sophisticated network services for efficiency and cost reduction.
WAN Operations and OSI Model
- WANs operate mainly at the OSI Model's Physical and Data Link layers, focusing on physical addressing and flow control.
- Various authorities set standards for WAN access including TIA/EIA, ISO, and IEEE.
Common WAN Terminology
- Customer Premises Equipment (CPE): Devices at the enterprise edge that connect to a carrier.
- Data Communications Equipment (DCE): Interfaces connecting customers to the WAN.
- Data Terminal Equipment (DTE): Devices sending data for WAN transmission.
- Demarcation Point: Divides customer and service provider equipment.
- Local Loop: Connects CPE to Central Office (CO).
- Central Office (CO): Service provider facility connecting to the network.
WAN Devices
- Dialup modem: Converts digital signals for public telephone networks.
- Access server: Manages dial-up communications.
- Broadband modem: Used with high-speed Internet connections, operating at higher frequencies.
- CSU/DSU: Ensures digital signal integrity and compatibility with LAN frames.
- Router: Connects networks and allows WAN access.
- Core router/Multilayer switch: Operates within the WAN backbone.
Circuit Switching
- Establishes dedicated channels between nodes before communication begins.
- Examples include PSTN and ISDN, with communication requiring completed connections prior to data exchange.
Packet Switching
- Splits data into packets routed over shared networks without pre-established circuits.
- Connectionless systems (e.g., Internet) carry full addressing in each packet, while connection-oriented systems (e.g., Frame Relay) utilize route identifiers.
- Packet switching tends to be cheaper than circuit switching but faces higher latency and jitter.
Purpose of WANs
- WANs connect LANs over larger geographic distances, interlinking enterprises with remote locations and branch offices.
- Service providers own WANs, unlike LANs, which are typically organization-owned. Fees are incurred for WAN services.
- WANs facilitate communication for remote sites, enabling data, voice, and video transport.
Necessity of WANs
- Without WANs, LANs remain isolated, hindering communication between distant sites.
- Businesses require inter-office communication for sharing data, especially for regional and branch offices.
- Increased connectivity needs arise from mobile employees and consumer interactions with online services.
WAN Topologies
- Various topologies are utilized to interconnect sites via WANs. Key examples include:
- Point-to-Point: Direct, dedicated connections like T1/E1 lines between two endpoints.
- Hub-and-Spoke: Central hub connects multiple spoke sites, facilitating shared access.
- Full Mesh: Allows direct communication between all sites but requires more virtual circuits.
- Dual-homed: Offers redundancy and load balancing, though more expensive and complex to set up.
Evolving Networks
- Companies focus on optimizing network efficiency to boost profitability during economic downturns.
- Networks must adapt as companies expand, illustrated by SPAN Engineering’s growth from local to global scale.
Small Office Setup
- SPAN Engineering has 15 employees, utilizing a single LAN for VoIP, peripheral sharing, and internet access via DSL.
Campus Network Expansion
- After five years, SPAN expands infrastructure, transitioning to several subnetworks within a multi-floor office building.
Branch Networking
- As SPAN opens branch offices, a WAN is implemented to enable remote access to the central data center.
- Local branches use dedicated lines, while international branches rely on the Internet for connectivity.
Distributed Network Maturity
- SPAN Engineering reaches a global presence with thousands of employees, requiring sophisticated network services for efficiency and cost reduction.
WAN Operations and OSI Model
- WANs operate mainly at the OSI Model's Physical and Data Link layers, focusing on physical addressing and flow control.
- Various authorities set standards for WAN access including TIA/EIA, ISO, and IEEE.
Common WAN Terminology
- Customer Premises Equipment (CPE): Devices at the enterprise edge that connect to a carrier.
- Data Communications Equipment (DCE): Interfaces connecting customers to the WAN.
- Data Terminal Equipment (DTE): Devices sending data for WAN transmission.
- Demarcation Point: Divides customer and service provider equipment.
- Local Loop: Connects CPE to Central Office (CO).
- Central Office (CO): Service provider facility connecting to the network.
WAN Devices
- Dialup modem: Converts digital signals for public telephone networks.
- Access server: Manages dial-up communications.
- Broadband modem: Used with high-speed Internet connections, operating at higher frequencies.
- CSU/DSU: Ensures digital signal integrity and compatibility with LAN frames.
- Router: Connects networks and allows WAN access.
- Core router/Multilayer switch: Operates within the WAN backbone.
Circuit Switching
- Establishes dedicated channels between nodes before communication begins.
- Examples include PSTN and ISDN, with communication requiring completed connections prior to data exchange.
Packet Switching
- Splits data into packets routed over shared networks without pre-established circuits.
- Connectionless systems (e.g., Internet) carry full addressing in each packet, while connection-oriented systems (e.g., Frame Relay) utilize route identifiers.
- Packet switching tends to be cheaper than circuit switching but faces higher latency and jitter.
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Description
Explore the key concepts of Wide Area Networks (WANs) in this quiz based on Chapter 2 of Connecting Networks v6.0. Learn about the purpose of WANs, their operation compared to LANs, and the role of service providers in offering WAN services. Test your understanding of how WANs connect enterprise and remote LANs.