A Wide Area Network (WAN) spans a large geographic area, such as a city, state, or even an entire country. The Internet is the largest and most well-known example of a WAN. It is a type of telecommunication network that connects devices across multiple locations worldwide.
WANs represent the largest and most expansive type of computer networks available today. These networks are typically established by service providers (ISP), who then lease their WAN services to businesses, schools, governments, or the public.
How WANs Are Connected
WANs
are typically composed of smaller networks (like LANs) and rely on various
technologies and infrastructure for connectivity. Here's an overview of how
WANs are connected:
1. Physical
Infrastructure
●
Leased Lines telecommunication company: Dedicated point-to-point connections provided by
telecommunication companies. These are private and offer reliable
communication. An Indian company like Tata Communications, among many others,
works to connect one country to another. These private companies coordinate
with the countries involved to establish WAN connectivity, ensuring that all
legalities are fulfilled.
●
Fiber Optic Cables:
High-speed and high-capacity links, such as those used in undersea cables for
intercontinental connections, are a key feature of WAN networks. The length of
fiber cables in a WAN network can range from 1,000 to 5,000 kilometres, making
them quite costly.
These cables are primarily laid by private companies under
the sea. You can even view these cable routes using maps designed for this
purpose.
The 2Africa submarine cable is the
longest in the world.
It stretches an impressive 45,000
kilometres, connecting 33 countries across three continents: Africa, Asia, and
Europe.
●
Satellite Links:
Used for remote or hard-to-reach locations where physical cabling is
impractical. Satellite networks use satellites orbiting Earth to relay signals,
enabling communication across vast distances.
●
Public Switched Telephone Network (PSTN): Legacy infrastructure used for dial-up or DSL-based WAN
connections.
●
Wireless Links:
Includes microwave links, 4G/5G cellular networks, or satellite systems like
Sta14rlink.
2. Networking Devices
●
Routers: Act as
intermediaries between LANs and WANs, determining the best path for data
packets.
●
Switches: Used
within WANs to route data efficiently between connected networks.
●
Modems: Convert
digital signals to analog (and vice versa) for transmission over certain types
of connections like DSL.
3. Connection Technologies
●
MPLS (Multiprotocol Label Switching): A private networking technology that offers efficient
routing and guaranteed performance.
●
VPN (Virtual Private Network): Creates secure tunnels over public networks, like the
internet, to connect different parts of a WAN.
●
SD-WAN (Software-Defined WAN): A modern technology that uses software to manage and
optimize connections, combining different types of links (e.g., broadband,
MPLS) for flexibility and cost savings.
●
Internet-based WANs:
Use the public internet as a backbone for connecting networks, often secured by
encryption.
4. Protocols and Standards
●
IP (Internet Protocol):
The primary protocol for routing data across WANs.
●
Frame Relay/ATM:
Legacy protocols for packet-switched networks.
●
Ethernet over WAN (EoWAN):
Extends Ethernet to WANs for high-speed, cost-effective connections.
5. Service Providers
WAN
connections are typically established through agreements with telecom companies
or ISPs. They provide the necessary infrastructure and services, including
leased lines, MPLS, or broadband.
6. Redundancy and Failover
To
ensure reliability, WANs often use:
●
Redundant Links:
Backup connections in case of failure.
●
Load Balancers:
Distribute traffic across multiple paths.
●
Dynamic Routing Protocols:
Such as OSPF (Open Shortest Path First) and BGP (Border Gateway Protocol) to
adapt to changes in the network.
What Is the Purpose of a WAN
Connection?
If WAN connections didn’t exist,
organizations would be isolated to restricted areas or specific geographic
regions. LANs would allow organizations to work within their building, but
growth to outside areas — either different cities or even different countries —
would not be possible because the associated infrastructure would be cost
prohibitive for most organizations.
As organizations grow and become
international, WANs allow them to communicate between branches, share
information and stay connected. When employees travel for work, WANs allow them
to access the information they need to do their jobs. WANs also help
organizations share information with customers, as well as partner
organizations, such as B2B clients or customers.
However, WANs also provide an
essential service to the public. Students at universities might rely on WANs to
access library databases or university research. And every day, people rely on WANs
to communicate, bank, shop and more.
|
WAN |
LAN |
MAN |
|
Wide Area Network |
Local Area Network |
Metropolitan Area Network |
|
A WAN network will have a larger coverage area that can range up to
100,000 KM and in some cases, stretches globally or over international
borders. |
A LAN network is limited to between 100-1000 meters coverage. |
A MAN network is will usually stretch up to an area of 100 KM. |
|
For data transfer, there is low bandwidth. |
For data transfer, there is high bandwidth. |
For data transfer, there is a moderate bandwidth. |
|
It will typically have a distributed ownership model. |
It is typically owned by an individual or an organization. |
It can be owned publicly or privately. |
|
It costs more to set-up a WAN than a LAN or a MAN. |
It has a low cost of set-up. |
It has a moderate cost of set-up. |
|
With a WAN, you can get lower speeds of data transfer of 10-20 Mbps. |
With a LAN, you can get higher speeds of data transfer with
10/100/1000 Mbps Ethernet (high speed). |
With a MAN, you can get speeds of data transfer up to 100 Mbps. |
