How Much Does an OCx Circuit Cost?

Cost Circuit

Cost Circuit

You ask for a general explanation of bandwidth cost and the factors impacting it. The best place to look is in your own question — you have already covered most of the factors!
Bandwidth is generally billed at either a flat rate (1.54 megabits/second for a whole month), or at a per-unit rate ($1.00 per gigabyte). The units can be measured over a period of time, or can be peak units. Each bandwidth provider has their own methods of accounting and billing.
Factors that can raise (or lower) the cost of bandwidth includethe volume needed – obviously Yahoo and Google are going to get a better cost per unit than you or I would. They also include the quality of service — a 99.99999 guaranteed uptime on the connection with multiple upstream providers and hot failover protection is a lot more costly than a simple T-1 from the local RBOC.
Additionally, location is going to have a lot to do with bandwidth charges. In a major metropolitan area with many bandwidth providers, the costs are going to be lower because of competition and exiting infrastructure. However, in rural Kansas, getting high bandwidth to the ranch will cost a significant amount more, simply because there are very few providers, and the line charges (especially if a new line has to be run!) are more. Less competition = higher costs. Less infrastructure = higher costs.
To address the core of your question, how cheap can *you* get it, I would need to know a lot more about your situation: Where are you? What do you want to do with the bandwidth? How much do you need? What level of service do you need? Could you be better served by colocating your hosts somewhere, and taking advantage of their bandwidth?
For example, if you have an office that needs internet connectivity for mail and light web browsing, a simple business DSL line for less than $100 a month would suit you well. However, if you are an adult video producer that wants to deliver all the video content over the web, you would be well suited to colocating your product with a major firm on one of the backbone lines in California or New York. You could still expect to see charges in excess of $5,000 a month.
In summary, location is the main factor in determining the prices of OCx circuits. It’s best to contact a service provider of these large circuits to determine the specific needs of your business, which will then give you a more accurate OCx price quote.
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