Professor Messer 1.2: Network Types & WAN Termination

peer-to-peer (P2P)

All devices are both clients and servers, allowing direct communication between devices. Advantages include easy deployment and low cost. Disadvantages include difficult administration and security challenges.

client-server network,

A central server facilitates communication, with clients communicating only with the server and not with each other. Advantages include improved performance and easier administration. Disadvantages include higher costs and increased complexity.

Local Area Network (LAN)

A network within a relatively small area, such as a building or a group of buildings, providing high-speed connectivity. Typically use Ethernet and 802.11 wireless technologies. If the connection is slower, it is not considered "local."

Metropolitan Area Network (MAN)

A large network that spans a city, larger than a LAN but often smaller than a WAN. Historically, used specific topologies, but now Metro Ethernet is commonly used. It's common to have government ownership since they control the right of way.

Wide Area Network (WAN)

Spans the globe, connecting LANs across long distances and generally operating slower than LANs. Uses various technologies, such as point-to-point serial and MPLS. Can be terrestrial or non-terrestrial, like satellite networks.

Wireless LAN (WLAN)

Uses 802.11 technologies to provide wireless connectivity within a building or a limited geographical area, allowing for mobility. Coverage can be expanded with additional access points to cover larger areas such as a downtown area or a large campus.

Personal Area Network (PAN)

A private network used for personal devices, utilizing technologies like Bluetooth, IR, and NFC. It can connect devices such as automobiles, wireless headsets, and mobile phones for functions like audio output and health monitoring. Also used for automatic recording and transmission of data from remote or inaccessible sources.

Campus Area Network (CAN) or Corporate Area Network

Covers a limited geographical area, such as a group of buildings within a campus. It uses LAN technologies, including high-speed Ethernet and fiber connections, typically owned and maintained by the organization itself without relying on third-party providers.

Network Attached Storage (NAS)

Provides shared storage across a network with file-level access, requiring entire files to be overwritten for any change, regardless of size. Requires significant bandwidth and may use isolated networks and high-speed technologies.

Storage Area Networks (SAN)

Offer block-level access, making reading and writing more efficient and giving the appearance of local storage. Requires significant bandwidth and may use isolated networks and high-speed technologies.

Multiprotocol Label Switching (MPLS)

Data is directed through a path via labels. Supports various transport mediums and protocols, accommodating different types of data. Labels are "pushed" onto packets as they enter the network and "popped" off as they exit.

Multipoint Generic Router Encapsulation (mGRE)

Widely used in Dynamic Multipoint VPN (DMVPN) to enable remote sites, or "spokes," to securely exchange data directly with each other without routing through a central VPN server or "hub." Allows VPNs to dynamically build and adjust as devices are added or removed, creating tunnels on-demand to form a dynamic mesh network.

Software-Defined WAN (SD-WAN)

Designed for cloud environments, optimizing for cloud-based applications. Allows cloud-based applications to communicate directly with the cloud, eliminating the need to route data through a central point.

demarcation point, or demarc

A network connects with the outside world, such as with a WAN provider or Internet service provider. Commonly found in various settings, including homes and central locations within buildings. Can be as simple as an RJ-45 connection. It serves as the boundary where customer premises equipment (CPE) connects. If issues arise, they can be checked on the provider's side, if none are found, the problem is likely on the customer’s side.

Smart Jack

The device that determines the demarcation point. More than a simple interface, it can be a circuit card in a chassis and provides advanced features beyond basic connectivity. Allows internet providers to perform remote tests, including built-in diagnostics, loopback tests, and alarm indicators for configuration and status monitoring.

A network topology in which each node has a direct physical connection to every other node is called:

Mesh

A network topology where each node connects to a central switching device is known as: (Select 2 answers)

Hub-and-spoke & Star

Which of the following network topologies is most commonly used in contemporary Ethernet LANs?

Star

Which of the following answers refer to the characteristic features of bus topology? (Select 3 answers)

The main network cable becomes a single point of failure, All network nodes connect to a single central cable (a.k.a. backbone or trunk), and A terminator at each end of the main network cable prevents collisions caused by signal bounce

Which of the following answers can be used to describe the characteristics of ring topology?

Network nodes are daisy-chained in a closed loop, data is passed through each intermediate node until the receiver node is reached, and each network node connects to exactly two other nodes

Which of the following statements apply to Peer-to-Peer (P2P) networking?

Less stable and secure than client-server networking model, decentralized network type, and In P2P networks, each node can at the same time serve and request resources

Which of the following answers can be used to describe client-server architecture? (Select 3 answers)

More stable and secure than peer-to-peer architecture, centralized network type, and less reliable than peer-to-peer architecture

The Internet is an example of a large public WAN.

The Internet is an example of a large public WAN.

True

A type of network consisting of computers and peripheral devices that use high-frequency radio waves to communicate with each other is called:

WLAN

A dedicated local network consisting of devices providing data access is called:

SAN

Virtual Networks:

A server farm with 100 individual computers connected via enterprise switches and routers, often with redundancy, can be migrated to a single physical server hosting 100 virtual servers. This consolidation maintains network functionality and efficiency while reducing physical hardware requirements.

Network Function Virtualization (NFV)

Replaces physical network devices with virtual versions managed from the hypervisor, which creates and runs virtual machines. These virtual devices offer the same functionality as physical ones, such as routing, switching, load balancing, and firewalls. Allows for the quick and easy deployment of network functions with a click from the hypervisor, eliminating the need for physical hardware. It supports various deployment options, including virtual machines, containers, and fault tolerance.

Hypervisor

Manages the virtual platform and guest operating systems, handling hardware management tasks such as CPU, networking, and security. It provides single console control, often referred to as a "pane of glass," for streamlined management.

vSwitch

Moves the functionality of a physical switch into a virtual environment. It offers similar functionalities, including forwarding options, link aggregation, port mirroring, and NetFlow for traffic monitoring. Can be deployed from the hypervisor and automated with orchestration tools.

Virtual Network Interface Card (vNIC)

Needed for a virtual machine to interface with a network. Configured and connected through the hypervisor, enables additional features such as VLAN aggregations and multiple interfaces, allowing for advanced network segmentation and communication.

Satellite networking

Providing non-terrestrial connectivity. It is relatively high in cost compared to terrestrial networking and commonly offers speeds of 50 Mbit/s down and 3 Mbit/s up. It is used for remote or difficult-to-network sites but has high latency, typically around 250 ms for both uplink and downlink. Operating at high frequencies around 2 GHz, require a line of sight and can suffer from rain fade, potentially losing connection during certain weather conditions.

Copper

Widely used in network installations due to its relative affordability and ease of installation and maintenance. However, it has limited bandwidth availability due to the physical limitations of electrical signals through it. Commonly used in wide area networks, such as cable modem and DSL connections, often combined with fiber where this material is used for the local loop and fiber for the backbone.

Asymmetric Digital Subscriber Line (ADSL)

Uses telephone lines and provides faster download speeds than upload speeds (asymmetric). It has a 10,000-foot limitation from the central office (CO), with common speeds around 200 Mbit/s downstream and 20 Mbit/s upstream. Faster speeds may be possible if the user is closer to the central office.

Cable broadband

Uses broadband transmission across multiple frequencies to support different types of traffic on the cable network.

DOCSIS

Data Over Cable Service Interface Specification

Fiber

Provides high-speed data communication using light frequencies, supporting very high data rates and long-distance transmission. It has a higher installation cost and more expensive equipment compared to copper, and repairs can be more complex. Used in the WAN core for large-scale installations and supports technologies like SONET (synchronous data transmission over optical fibers) and wavelength division multiplexing (WDM). Increasingly being deployed to business and residential premises.

Metro Ethernet

Metropolitan-area network that connects geographically separated enterprise LANs across a metropolitan area using Ethernet. It is a common standard with an optical provider network, utilizing local fiber networks and wavelength division multiplexing (WDM) for high-speed data transmission across multiple wavelengths of light.