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MODULE 7: CONCEPTS OF WAN, image, image, image, image - Coggle Diagram
MODULE 7: CONCEPTS OF WAN
7.4 Modern WAN connectivity.
2.- Modern WAN Connectivity Options
Dedicated: Dark fiber (high-speed, secure private connections).
Packet-switched: Ethernet WAN, MPLS.
Internet-based: Broadband VPN, xDSL, municipal Wi-Fi, satellite, WiMAX.
Ethernet WAN
Fiber optics (IEEE 1000BASE-LX up to 5 km, IEEE 1000BASE-ZX up to 70 km) have become a viable option.
Available services: Metro Ethernet, Ethernet over MPLS, and VPLS.
1.- Evolution of the WAN
Traditional WAN options are falling into disuse due to cost, availability, and limited bandwidth.
New options include cellular, wireless, satellite, fiber optic, DSL, and coaxial cable.
4.- MPLS (Multiprotocol Label Switching)
High-performance technology for interconnecting clients regardless of the access method.
Compatible with Ethernet, DSL, Cable, and Frame Relay.
Uses labels in packets to improve routing and optimize traffic.
Provides quality of service (QoS), redundancy, and support for VPNs.
7.5 Internet-based connectivity
4.- Connectivity Security
Use VPNs, firewalls, and encryption to protect information on public networks.
3.- IP Addresses
They can be static (fixed) or dynamic (they change with each connection).
Connection Types
Dedicated (always on, like fiber optic or cable).
Switched (requires dial-up, like dial-up).
1.- Internet connectivity
This is achieved through various technologies such as fiber optics, DSL, cable, satellite, and mobile networks.
5.- Key Protocols
HTTP/HTTPS, DNS, TCP/IP, NAT, and DHCP facilitate connectivity and secure access to the Internet.
7.3 Traditional WAN Connectivity
Circuit Switching
Definition: Establishes a temporary dedicated circuit for communication.
Common Technologies:
PSTN (Public Switched Telephone Network):
Uses modems to convert digital data into analog.
Limited speeds (<56 kbps).
Considered a legacy technology.
ISDN (Integrated Services Digital Network):
Allows digital transmission over telephone lines.
Speeds from 45 kbps to 2.048 Mbps.
Also deprecated due to faster technologies such as DSL.
Packet Switching
Definition: Segments data into packets that are routed through a shared network.
Common Technologies:
Frame Relay:
Layer 2 technology for interconnecting LANs.
Uses PVCs (Permanent Virtual Circuits) identified by DLCIs.
Speeds up to 4 Mbps.
Replaced by Metro Ethernet and Internet-based solutions.
ATM (Asynchronous Transfer Mode):
Uses fixed 53-byte cells (5 bytes header + 48 bytes data).
Ideal for voice and video due to its low latency.
Less efficient than Frame Relay for data.
Also replaced by more modern technologies.
Dedicated Connections (Leased Lines)
Definition: Permanent point-to-point connections between two locations.
Common Technologies:
T-carrier: Used in North America (T1: 1.544 Mbps, T3: 43.7 Mbps).
E-carrier: Used in Europe (E1: 2.048 Mbps, E3: 34.368 Mbps).
Advantages:
Guaranteed bandwidth.
Secure and reliable connection.
Disadvantages:
High cost, especially for long distances. Inflexibility for rapid changes.
7.1 Purpose of WANs
7.1.1 LAN and WAN
LAN (Local Area Network): A network limited to a small area (office, home).
WAN: Connects multiple LANs, covering large areas
Differences:
LAN: High speed, shorter range.
WAN: Longer range, slower speed.
7.1.2 Private and Public WANs
Public WAN: Open access network infrastructure (Internet, telecommunications providers).
Private WAN: Dedicated network owned by a company or entity (more secure, private).
Example of a public WAN: Internet.
Example of a private WAN: Private corporate network or VPN.
7.1.3 WAN Topologies
Point-to-point topology: A direct connection between two locations.
Mesh topology: A connection between multiple locations, each connected to all the others.
Ring topology: A connection in the shape of a circle, where each node is connected to the next.
7.1.4 Carrier Connections
Carrier (ISP): Internet service provider.
Carrier Connections: These are physical or virtual links between WANs.
Connection Types: Fiber optic, DSL, satellite, leased lines.
7.1.5 Network Evolution
Legacy networks: Circuit-switched technology.
Current networks: Packet switching (more efficient, flexible).
Trends: 5G, SD-WAN, software-defined networking (SDN).
Evolution: From monolithic networks to more agile and distributed networks.
7.2 Functions of WAN
WAN Standards:
Modern WANs follow regulations from TIA/EIA, ISO, and IEEE, ensuring standardized network communications.
WAN in the OSI Model:
Layer 1: Defines transmission protocols such as SDH, SONET, and DWDM.
Layer 2: Defines data encapsulation methods, including DSL, Ethernet WAN, MPLS, PPP, HDLC, Frame Relay, and ATM.
WAN Terminology and Devices:
Covers key terms and hardware components used to connect businesses to service providers.
Serial Communication:
Transmits data bit by bit over a single channel, unlike parallel communication.
Circuit-Switched Communication
Establishes a dedicated circuit before data transmission.
Inefficient for data since bandwidth remains reserved even when not in use.
Example: Traditional telephone calls.
Packet-Switched Communication
Divides data into packets that are dynamically routed through the network.
More efficient and flexible than circuit-switched communication.
Key technologies: MetroEthernet, MPLS, Frame Relay, and ATM.
Optical Transmission Technologies
SDH and SONET: Fiber optic standards ensuring reliable data transmission.
DWDM: Enhances bandwidth by transmitting multiple signals over different light wavelengths.
