High speed communications lines progressed from copper analog to copper digital to fiber optic digital over most of the last century. The technology that drives fiber has also evolved from time sliced synchronous multiplexing to packet based protocols, mirroring the transition to networked computing for nearly every business. While older SONET telco lines still provide effective connections, there are real advantages to be gained by upgrading to Ethernet WAN, the newer technology for fiber optic service.
It Started With Really Fast Phone LinesSONET, which stands for Synchronous Optical NETwork, is a phone company invention that was developed to bundle or multiplex thousands of individual phone calls onto an optical fiber for long distance transmission. To make operations easier, SONET was made backwards compatible with legacy T1 service that does exactly the same thing with 24 calls over two twisted copper pair… in other words, ordinary telephone line.
SONET allowed the phone companies to bundle T1 line into DS3 lines into OC3 fiber lines and demultiplex or unbundle them anywhere along the way. Everything was compatible down to the single telephone channel.
SONET to Link Computers
So, how did SONET come to support computer networking? The protocol had to be converted between SONET’s time division multiplexing and Ethernet’s packet switching. That was accomplished using protocol conversion on a plug-in module. To the user, It made no difference what was going on under the hood. Packets would go in one router and come out another miles or thousands of miles away.
SONET was developed for fiber and all of the early fiber optic links for computer networks were connected using one of the SONET levels. OC3 was the lowest speed at 155 Mbps. This was the first fiber service that most corporations ordered when they outgrew their T1 and T3 lines. Each increase in speed required swapping out an adaptor module for the particular SONET level.
In fact, the Internet was built on SONET. SONET rings, which offer redundant paths, formed the core of the Internet as it grew. Internet service providers would connect via SONET and then divvy up the bandwidth for multiple 64Kbps dial-up modems or, later, DSL or Cable broadband modems.
The Ethernet Revolution
Ethernet, developed by the Xerox Palo Alto Research Center in the mid to late 1970’s, grew to become the dominant networking protocol, thanks in no small part to the proliferation of the personal computer at the same time. Most small and large users adopted Ethernet, as adaptor cards, cabling, hubs and routers became more and more affordable. Every PC soon came with an RJ-45 Ethernet jack as standard equipment and peripherals, such as printers, did the same for compatibility.
Once Ethernet became the de-facto networking standard and computer data traffic greatly exceeded voice traffic, it started to make sense to just adopt Ethernet for Wide Area Networks as well as Local Area Networks. When business phones became digitized and used VoIP to connect on the same network as the computers, the need for a separate voice network faded away.
Another factor that has moved WAN services from SONET to Ethernet is the rise of competitive network service providers independent of the telephone companies. Since these companies had no legacy analog phone service to support, they could simply focus on offering Ethernet connections to their customers in competition to the telcos.
By this time the original Ethernet protocol has been expanded to provide technical specifications for Carrier Ethernet, which is the same as LAN Ethernet but extended to support the MAN (Metropolitan Area Network) and WAN (Wide Area Network).
What Ethernet WAN Has to Offer
You remember that SONET has distinct service levels, each with it’s own bandwidth and specific adaptor requirements. Ethernet doesn’t have this limitation. Instead, you have an Ethernet port with a maximum bandwidth, say 1 Gbps. It will support any bandwidth up to the max limit of 1 Gbps. You can order 100 Mbps service today and easily upgrade to 500 Mbps or 1 Gbps later. Only if you want a service level above 1 Gbps, will you need to have a higher capacity port installed. This process is so seamless that many providers will let you change service levels at will by logging into your online account.
Ethernet services tend to be less expensive than SONET. Usually, much less expensive. You pay for the service level you want, be it 10 Mbps, 100 Mbps, 1 Gbps, 10 Gbps, and so on. Remember you can change this easily after you have service installed and your bill will be adjusted to the new level you select.
Since there are many, many competing Ethernet MAN and WAN service providers, pricing per Mbps has dropped rapidly over the years and continues to do so. Some of the service providers are the traditional telephone companies, but with much improved pricing. Others are independent carriers serving regional, national, or international areas. They can also provide excellent customer service, high reliability, and very good deals on bandwidth.
There are usually two types of service you’ll be interested in. One is a dedicated connection to the Internet at a bandwidth you select. The other is a point to point dedicated private line that is just like having a very long Ethernet cable connecting two LANs separated by many miles. These are useful for interconnecting main offices and branch offices, warehouse, manufacturing centers and so on with maximum performance and privacy. Another popular application is a direct connection between your offices and your cloud service provider. This avoids the vagaries of Internet performance and makes the cloud seem like it is right down the hall.
Perhaps you still have legacy SONET service that was installed years ago. It’s been working fine so no one has paid much attention. This would be a good time to see if competing Ethernet WAN services can give you more bandwidth for the same budget or offer a considerable cost savings if you are happy with the bandwidth level you have now. It doesn’t cost anything to look, so why not see what’s available?
