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Software-Defined for a Wide-Area-Network | SD-WAN

Software-Defined WAN, or SD-WAN for short, is a technology that gives new meaning to wide area networks.

Software-Defined WAN, or SD-WAN for short, is a technology that gives new meaning to wide area networks. First, a wide area network interconnects many local area networks – LANs. The LANs are connected to the WAN via routers or other devices. Without the wide area network, users would not be able to share applications and other resources that are centrally located.

WAN Connections and Ownership

Wide area network connections might include T1s, multiprotocol label switching, commercial broadband internet lines and carrier Ethernet. WAN connections may also be wireless, such as the 4G LTE networks that are common for cell phones.

WANS may be leased from an internet service provider, telecommunications carrier, cable company or an IP network provider. The WAN infrastructure could also be privately owned. If it’s privately owned, the WAN is operated over a private connection that is dedicated. If it’s leased as a service, the WAN is provided over a public medium, such as the internet. A hybrid WAN uses public and private services.

A traditional WAN starts at the branch office, then goes through several routers – one for DSL, one for fiber optics and one for LTE. It then goes through another set of routers for each type of wired or wireless connection to the HQ data center or a cloud provider.

An SD-WAN, or software-defined wide area network starts out at the same branch office, then goes through an SD-WAN router, which sends the signal over DSL, fiber optics or LTE connections, then over the public internet, and then through wired connections – DSL or fiber optics – into another SD-WAN router, and then int the HQ data center or a cloud provider.

What is a Software-Defined Wide Area Network?

A hybrid WAN uses a combination of private and public protocols to send data. For example, a hybrid WAN might start out as a private wide area network but will use the internet to connect to the cloud. A software-defined WAN makes the hybrid connections easier for businesses to set up, use and manage. The two functions of an SD-WAN are connecting many public and private WAN links and automatically selecting the best path for data traffic based on the current connections.

Generally, when a wide area network goes down, it is a result of the network. Using an SD-WAN eliminates many of the performance issues of a wide area network with several different techniques including:

  • Protocol optimization;
  • Deduplication;
  • Traffic shaping;
  • Compression; and
  • Local caching.

The network is less expensive to set up because it uses lower-cost bandwidth connections, such as any of the commercial internet services.

The evolution of IT technologies has altered traffic flows within distribution organizations. Not only do remote users require significantly more bandwidth, but they also need to directly access SaaS/cloud-based applications such as Salesforce, Office 365, Lync and off-premise storage (such as Dropbox, Evernote, and so on). 

Benefits of Using SD-WAN

Several of the benefits of converting to SD-WAN include endpoint flexibility, better security for hybrid networks, real-time application optimization and a major reduction in the cost per Mbps. A large company could see a reduction of $20 million or better in operating expenses over a few years. Of course, there is the better uptime since SD-WAN doesn’t crash as often as the wide area network. The time to install the system is also considerably less.

You’ll also have advanced analytics including sophisticated forecasting, visibility of applications for fast failure correlation and “what-if” analysis to help with resource planning.

Contact PS Lightwave

For more information on software-defined wide area networks or SD-WANs, contact PS Lightwave for a consultation. We’ll discuss your network needs, including bandwidth and the complexities of your system.

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PS LIGHTWAVE, a leading telecommunications service provider headquartered in Houston, Texas, provides managed Ethernet Data Circuits, Internet, private network solutions and Voice over IP (VoIP) over one of the nation’s largest facilities-based private Metropolitan Area Networks (MANs). The switched Layer 2 network, backed by 24/7/365 Network Operations Center (NOC) support, encompasses approximately 5,500 route miles and 1,400 on-net locations and connects 100+ fault-tolerant multi-gigabit Ethernet rings for built-in redundancy, security, low latency, and high-availability. At PS LIGHTWAVE Great Connections Happen Here™.

For more information, please visit or call 832-615-8000.