Hardware Reference
In-Depth Information
at a party: The more users of a high-speed connection, the slower each part of it will be.
To keep user connections fast while growing, ISPs add full or fractional T-1 lines to their
points of presence. Or, they might switch from a T-1 connection to the even faster T-3, if
available.
Note
Equivalentinthroughputtoapproximately28T-1lines,aT-3connectionrunsat45Mbpsand
is suitable for use by large networks and university campuses. Pricing information falls into
the “if-you-have-to-ask-you-can't-afford-it” category.
With the rise of the Internet and the demand for high-speed data access for networks, the
price of T-1 links in the United States has fallen drastically since the late 1990s, although
youwillstillpayinthehundredsofdollarsfortypicalserviceofferings.T-1servicecanbe
acquired from either your local telco or third-party firms. Fractional T-1 or burstable T-1
(whichallowsyoutohavedifferinglevelsofbandwidth,uptotheentireT-11.5Mbps,de-
pending on demand) costs less than full T-1 service. For a large organization that requires
a lot of bandwidth, the lower cost of T-1 services today make installing a higher-capacity
service and growing into it—rather than constantly upgrading the link—more economical
than ever.
Comparing High-Speed Internet Access
One way of making sense out of the confusing morass of plans available from cable mo-
dem,DSL,fixedwirelessInternet,andsatellitevendorsistocalculatetheaveragecostper
Mbpsofdatadownloaded($/Mbps).Youcancalculatethisfigureyourselfbydividingthe
service cost per month by the rated or average speed of the service:
Cost ($) / Speed (Mbps) = $/Mbps
You can use this formula with any broadband or dial-up service to find the best values.
Note that this simple calculation doesn't take into account the cost of any required equip-
ment, such as modems, filters, satellite dishes, and so on. If you must pay extra for equip-
ment or installation upfront, divide the upfront cost by the number of months you plan to
keep the service and add the result to the monthly service charge to get an accurate figure.
Note
The examples in this section assume unlimited usage. If you use metered broadband (avail-
able in some cable and many wireless data plans), be sure to add in the cost of any overages
you typically incur in a billing cycle.
