Revolutionizing WAN: SD-WAN vs. Traditional WAN Explained

Posted on May 31, 2024 by

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In modern enterprise networks, Wide Area Networks (WAN) connect geographically dispersed sites to ensure data communication across locations. There are now two main implementations in this field: Traditional WAN and Software-Defined Wide Area Network (SD-WAN). This article will outline the definitions of these two technologies, their similarities and differences, as well as their respective advantages and disadvantages, to help decision-makers better understand how to choose the right solution for their network requirements.

Overview of SD-WAN & Traditional WAN

Traditional WAN Definition

A Traditional Wide Area Network (WAN) is a method of connecting multiple geographically dispersed locations using a dedicated infrastructure involving routers and leased lines such as MPLS (Multiprotocol Label Switching), T1 circuits, or other private connections. It relies heavily on physical hardware and manual configuration to route and manage network traffic. Traditional WANs are typically implemented to ensure reliable communication within organizations, often utilizing proprietary or leased circuits from telecommunications providers to achieve stable and predictable performance.

SD-WAN Definition

Software-Defined Wide Area Network (SD-WAN) is an advanced WAN management approach that decouples the network control layer from the hardware and leverages centralized software to manage traffic across multiple types of connections such as MPLS, broadband internet, and LTE. SD-WAN uses software-defined networking (SDN) principles to optimize the routing of traffic dynamically based on current network conditions and application requirements. This approach enhances flexibility, scalability, and cost-efficiency, making it an ideal solution for modern, cloud-centric environments.

SD-WAN vs. WAN

SD-WAN

Similarities between SD-WAN and Traditional WAN

While SD-WAN and Traditional WAN are fundamentally different in their architecture and management, they share some core similarities:

1. Purpose: Both SD-WAN and Traditional WAN are designed to connect geographically dispersed locations and provide a means for reliable communication and data transfer between different business sites.
2. Use of Routers: Both types employ routers or similar network devices to direct traffic between different network nodes.
3. Support for Multiple Sites: Both can be deployed to support multiple branch offices, remote locations, and data centers.
4. Security Measures: Both include security features to protect data in transit, such as encryption, firewalls, and access control lists (ACLs).
5. WAN Technologies: Both can utilize technologies like MPLS (Multiprotocol Label Switching), broadband internet, and LTE. Traditional WANs primarily rely on MPLS, while SD-WAN can also incorporate broadband and LTE more flexibly.
6. Reliability and Performance: Both aim to ensure reliable network performance and minimize downtime, although they achieve this through different methods.

Differences between SD-WAN and Traditional WAN

	Traditional WAN	SD-WAN
Architecture	Relies on hardware-centric architecture with dedicated routers and leased lines.	Uses software-defined networking principles to separate the control plane from the data plane, allowing centralized management.
Management	Requires manual configuration and management of each network device. Changes and updates are often time-consuming and labor-intensive.	Offers centralized, software-based management, allowing network administrators to manage and configure the entire WAN through a single interface. This facilitates easier and quicker updates and changes.
Flexibility	Mainly uses MPLS circuits and other leased lines, which can be costly and inflexible regarding bandwidth changes and scalability.	Can use a mix of connection types, including MPLS, broadband, and LTE, and dynamically route traffic based on real-time network conditions, offering greater flexibility and scalability.
Cost	Generally more expensive due to the reliance on leased lines like MPLS and the need for specialized hardware at each site.	Can reduce costs by using public internet connections and eliminating the need for expensive leased lines and specialized hardware.
Performance Optimization	Performance is generally static and relies on the underlying leased lines' quality and capacity.	Optimizes performance dynamically using techniques like Application-Aware Routing and Dynamic Path Selection to ensure optimal performance for critical applications.
Deployment Time	Setting up new branches or modifying existing ones usually takes more time due to the need for physical hardware installation and configuration.	Faster to deploy as it relies more on software configurations and can quickly establish connections using existing internet infrastructure.
Security	Security features are implemented through standalone firewalls, ACLs, and other security appliances, often requiring additional hardware.	Built-in security features such as end-to-end encryption, secure tunnels, and integrated firewalls provide a comprehensive security approach.
Scalability	Scaling requires significant investment in new hardware and leased lines.	Easily scalable through software adjustments and the use of diverse connection types, making it ideal for growing businesses and cloud-centric applications.

Advantages of SD-WAN

1. Cost Savings

Reduced Hardware Costs: Uses existing IP-based connections like broadband, eliminating the need for expensive leased lines.

Lower Operational Expenses: Simplifies network management and reduces dependency on costly MPLS circuits.

2. Scalability

Easy Expansion: Adding new sites is straightforward—simply integrate additional nodes without complex setups.

Adaptable Growth: Quickly adjust and grow your network as business needs evolve.

3. Security

Encryption: Uses SSL/TLS to secure data transmission over the public internet.

Integrated Security: Often includes built-in firewalls and intrusion prevention systems for comprehensive protection.

Conclusion

Both SD-WAN and traditional WAN are used to connect different geographic locations, but they differ significantly in architecture, management, and operational efficiency. Traditional WAN relies on dedicated hardware and leased lines, making it costly and inflexible with complex configurations. SD-WAN uses software-defined networking principles, leveraging connections like broadband and LTE, offering lower costs, easier scalability, and higher security, making it a more attractive choice.

If you want to know more about SD-WAN, you can read SD-WAN, FS provides Internet Data Center solutions to Meet Diverse Business Needs.