Wednesday, July 01, 2009

WAN Topology Options

You have options when it comes to connecting to branch offices, franchisees, suppliers, customers and remote workers. Which particular topology will work best depends on what you are trying to accomplish. Are you simply trying to perform overnight backups to a off-site data center across town? Or do you need to create a virtual company by interconnecting principals in a half dozen states like they were in the same building? Let's have a look at some popular WAN topologies being used today.

The most ubiquitous WAN or Wide Area Network is the Internet. It goes everywhere and connects nearly everyone. It's the ultimate mesh network. Connections to the Internet are relatively cheap and available in many forms, from wireline to wireless to fiber optic. So what limits Internet performance? There are two problems, really. One is security and the other is performance predictability.

The fact that everyone's connected to the Internet means you have to take special measures if you hope to keep your private business information private. That means encryption of your data during transmission and while it is resident in facilities you don't control, like remote storage. The VPN or Virtual Private Network is a software solution that creates private tunnels through the Internet by encrypting and decrypting your data. It's a popular solution for remote workers who will connect to the company servers using their home Internet connections and need to access sensitive information.

Performance is another matter. The Internet is a public utility. You have no control over who uses it or for what purpose. Fluctuations in bandwidth are commonly experienced by residential users on DSL and Cable broadband, both of which are "best effort" shared use services.

The Internet is designed to accommodate a high volume of traffic generated by an enormous number of users and to do this reliably. It is self-healing in that a failed router or cut line will be bypassed and other paths used. For those reasons, characteristics such as jitter, latency and packet loss are not guaranteed and can be expected to vary. This is no problem for data transmission using TCP/IP, the popular protocol for transporting packets. But it can wreak havoc on real-time services such as VoIP telephone and Video conferencing.

Business grade Internet connections function much better than consumer oriented services. But if you want to maintain control of your network quality over distance, you need to get off the Internet and use a private network service. In the past, Frame Relay was the way to go. Today, MPLS or Multi-Protocol Label Switching networks are the WAN solution of choice. In essence, the bandwidth you need is reserved for you by the network operator and only those locations you specify can be part of your network. That improves both stability and security.

MPLS is a mesh networking topology. Each location connects to the network "cloud" via a T1 line or higher bandwidth option such as DS3 or Gigabit Ethernet. The network operator provides a high performance fiber optic core network for the majority of the connection distance.

But what if you only need to connect two locations? Point to Point dedicated private lines are the traditional and often lowest cost solution. Security issues are minimized because you have exclusive use of the lines themselves. When you aren't transmitting data, they simply idle.

You can expand the point to point solution to more locations, usually by establishing a star network with the headquarters location as the hub. It becomes a cost tradeoff as to when an MPLS network becomes the better solution as the number of interconnected locations increases.

Which WAN topology is right for your situation? You need to know the options and the best way to find them is to get competitive quotes on WAN services for your business locations. There is no cost for this service to serious business users and expert consulting is included to help you sort out the myriad of options available today.

Click to check pricing and features or get support from a Telarus product specialist.

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