The digital age thrives on the efficient transmission of data across vast networks. This intricate web of connections relies on two fundamental technologies – switched networks and routed networks. While both facilitate communication, they operate in distinct ways, serving different purposes within the larger network infrastructure.
This article aims to clarify the key differences between switched networks and routed networks and describe their functionalities and applications.
What is a Switched Network?
A switched network connects devices within a local environment, such as a local area network (LAN). The primary device in this setup is a network switch, which uses Media Access Control (MAC) addresses to forward frames. When a device sends data, the switch checks its MAC address table and delivers the packet only to the intended recipient instead of broadcasting it to all devices.
Key features of switched networks include:
- Layer of operation: Data Link Layer (Layer 2 of the OSI model).
- Addressing scheme: Uses physical MAC addresses.
- Efficiency: Reduces unnecessary traffic by forwarding data selectively.
- Example use case: Office LANs or data centre interconnections.
What is a Routed Network?
A routed network connects multiple networks or sub-networks, typically spanning broader geographical areas. Routers act as the key devices, directing packets based on IP addresses. Unlike switches, routers operate at the Network Layer (Layer 3) of the OSI model and use routing tables to determine the optimal path for data delivery.
Key features of routed networks include:
- Layer of operation: Network Layer (Layer 3).
- Addressing scheme: Uses logical IP addresses.
- Routing protocols: Supports static and dynamic routing protocols like OSPF, RIP, or BGP.
- Example use case: Connecting branch offices across cities or linking corporate LANs to the internet.
Core Differences between Switched and Routed Networks
1. Layer of Operation
The most fundamental difference lies in the OSI model layer. Switches operate at Layer 2, dealing with frames and hardware addresses. Routers function at Layer 3, handling logical addresses and network-wide packet routing.
2. Addressing Method
Switched networks rely on MAC addresses, which are hard-coded into devices. Routed networks use IP addresses, which are logical and can be configured or changed based on network needs.
3. Protocol Dependency
Switches are largely protocol-independent because they forward traffic based on hardware addresses. Routers, however, depend on routing protocols and algorithms to choose the best path.
4. Scope of Communication
Switched networks are typically confined to smaller environments, such as a single building or office, where devices are closely interconnected. Routed networks operate on a broader scope, managing communication across multiple LANs, WANs, or the internet.
5. Traffic Handling
In a switched network, traffic is segmented at the port level, and data is forwarded directly to the target device. Routers perform more complex functions, such as filtering traffic, avoiding congestion, and preventing loops.
6. Performance and Latency
Switched networks generally offer lower latency due to simple frame forwarding. Routed networks, while more complex, introduce slightly higher latency because of routing calculations and packet inspection.
7. Scalability
Switched networks are suitable for small to medium setups but face scalability issues when large numbers of devices are involved. Routed networks handle scalability better, accommodating large-scale enterprise infrastructures with thousands of nodes.
8. Security Functions
Switches offer basic security features like VLAN segmentation, while routers provide advanced security measures such as Access Control Lists (ACLs), firewall capabilities, and packet filtering.
Which One Should Organisations Use?
The choice between switched and routed networks depends on scale, purpose, and budget. Small offices may function efficiently with a switched network, while enterprises handling sensitive data and multiple sites require routed networks. In practice, modern infrastructures use a combination of both. For instance, a company might deploy switches to connect local devices within each branch and use routers to connect branches over a wide area network.
Conclusion
Switched and routed networks differ in their operational layers, addressing methods, scope, performance, and security. Switched networks excel in localised, high-speed environments, offering simplicity and affordability. Routed networks, on the other hand, provide broader connectivity, enhanced security, and scalability, making them indispensable for large organisations and internet-based communication.
In essence, switches form the building blocks of local communication, while routers act as the navigators of global data exchange. Understanding the strengths and limitations of both ensures informed decisions in network design, ultimately leading to more reliable and secure digital infrastructure.
