For large enterprise-level companies, choosing an Internet access method is relatively easy. Fire up the dedicated leased lines (and make mine a T-3, please), and shell out hundreds or thousands of dollars per month to the Telco and ISP—and don’t forget the setup fees and cost of customer premise equipment (CPE).
Many small and medium size businesses also need reliable and reasonably fast Internet access, but they may not be able to afford T-carrier and other traditional commercial options. Cost and quality are often a trade-off, but awareness of the many options available makes it easier for you to select the most cost-effective and task-effective alternative. In this article, I will examine the different bandwidth factors you need to consider, and then I will discuss the traditional business Internet access options.
How much speed do you need?
Although it’s generally true that faster is better, it’s important to evaluate your company’s real needs against the increased cost that, as a rule, comes with increased bandwidth, and to understand just how buzzwords such as speed and performance really correlate. To get the best solution for the least amount of money, you’ll need to consider a number of factors.
Evaluating bandwidth issues
Bandwidth, in this context, refers to the amount of data that can be transmitted over a link during a specified period of time. Network bandwidth is usually expressed in bits per second (bps), kilobits per second (Kbps), or megabits per second (Mbps).
Mbps isn’t everything
In considering differences between two connections (or connectivity types), you’ll want to consider at least three factors:
- Speed (expressed as Mbps for high speed connections)
- Reliability or uptime (the percentage of time that the link is “up” or functioning)
- Latency (the total amount of delay between the time a packet is sent and the time it arrives at its destination)
The least understood of these factors is latency. It is a product not only of the speed of the link on which the packet is transmitted, but also the time it takes network devices—such as routers—to examine the packet and forward it on its way. Latency often refers to the time it takes a connection to “get started,” and is based on the round-trip travel of a message and response from a sender to a destination and back again. That is, you might have excellent download speed with a specific connection but have to wait a significant amount of time between the time you enter the command to download and the time the destination server responds and starts sending. That’s called high latency. High latency can be caused by a large number of devices between the sender and destination, or it can be caused by a long distance that must be traveled by the packets (as with satellite connections, where the data must travel all the way up to geosynchronous orbit (22,300 miles above the equator) and back down again).
Traditional business options
The traditional choice for business connectivity—both in terms of connecting to the Internet and connecting the local networks of branch offices together—has been the dedicated leased line. This is a point-to-point physical connection (for example, between your company’s network—actually, its router—and your ISP). Typically, this is a T-carrier (T-1 or T-3 line). Another type of dedicated link is frame relay, which is a one-to-many connection that uses virtual links between your network (and those of many other companies) and the Telco’s frame relay network. Another Internet connectivity choice that was very popular for businesses several years ago and is still available (although its market has been cut into somewhat by the advent of broadband technologies) is integrated switched digital network (ISDN). These three traditional business options have one thing in common: rock solid reliability. Here is a look at the other advantages—and disadvantages—of each.
T-1: It’s not just for millionaires anymore
A decade ago, T-1 was out of the reach of almost all individuals and most businesses. At several thousand dollars per month, it was a significant expense even for medium size companies. Today, it’s possible to get a full 1.544 Mbps T-1 line in many locations in the U.S. for $500 per month or less. While still quite a bit more expensive than broadband (for similar speed), a dedicated leased line typically experiences far less downtime. There is a charge for the local loop from the Telco and a charge for service from an ISP. These charges are often combined on one bill. You’ll need to rent or purchase a channel service unit/data service unit (CSU/DSU) and a router, as well.
T-1 runs over either copper wires or fiber optic. Each T-1 line carries 24 64-Kbps channels. It is also possible to purchase a “fractional T-1,” or only some of the channels, for a lower total bandwidth. A full T-1 can support a hundred or more users performing low-bandwidth activities, such as Web browsing and e-mail.
T-1 can be used for voice lines as well as data (each of the 24 channels is used for one voice line).
The phone company generally installs T-1 service as two redundant lines so that if one goes down, service can be switched to the other. Response to problems of T-1 customers by both the Telco and ISPs is usually immediate. Your T-1 contract may come with a “guaranteed bandwidth” clause; in other words, with T-1, what you expect (1.544 Mbps) is what you get—unlike with many DSL and cable modem contracts, where you are promised bandwidth “up to” a particular level, but your speeds may fluctuate. This is often called a committed information rate (CIR). If your company’s business depends on its Internet connectivity and requires high speed and guaranteed uptime (for example, if you host Web sites for others or run an e-commerce site for sales), T-1 may still be your best bet. This is especially true in a geographic area where low cost T-1 service is available.
Don’t dismiss T-1 as “too expensive” for your small business without doing some checking. I’ve seen some amazing deals (in the range of $300 per month) in some areas. T-1 service prices can vary widely within a locality, too, so check with more than one ISP.
Higher bandwidth leased lines (T-3 at 43.232 Mbps up to OC48 at 2.5 gigabits per second) cost thousands of dollars per month and are generally not financially feasible for most small businesses (nor do small businesses need the amount of bandwidth they provide). If your business is a heavy user of extremely high bandwidth applications, however, you can purchase more than one T-1 and aggregate the bandwidth.
Frame Relay: Low cost, moderate speed, high reliability
Frame relay uses two-way data paths called virtual circuits (either virtual switched circuits or virtual permanent circuits) between two locations, such as your company network and your ISP. For detailed technical data on how the technology works, see the Basic Guide to Frame Relay Networking. Frame relay works best with so-called “bursty” applications (where data is sent in bursts with time in between) rather than with those that need a steady stream.
Frame relay acts much like a dedicated line and gives you similar reliability and a CIR, but because the circuit is virtual (and thus the same frame relay switch can support more than one circuit), it costs less. You can usually purchase CIRs anywhere from 56 Kbps up to 1.544 Mbps. The CIR is your guaranteed minimum speed, but you will probably get higher “burst” speeds (for short amounts of time). Customer premise equipment requirements are the same as a T-1 (CSU/DSU and router).
ISDN: Going, going but not gone
ISDN comes in two varieties: basic rate ISDN (BRI) and primary rate ISDN (PRI). The first is a relatively low bandwidth solution, with two 64 Kbps data channels and a 16 Kbps control channel for total throughput of 128 Kbps (or you can use one channel for data and one for voice simultaneously). It is extremely reliable and bandwidth doesn’t fluctuate. A BRI line from the Telco generally costs less than $100. ISDN ISP services come in two types: dial-up or dedicated (always on). Dial-up is comparable in price to dial-up analog modem pricing ($25 per month or less). Dedicated service varies widely in price, up to several hundred dollars per month, depending on the ISP.
BRI service is an option to consider if you have only a few low bandwidth users (under 10) but need high uptime/reliability. An example would be a small business that uses the Internet primarily for e-mail and a little Web research, but which cannot afford to be without e-mail communication for hours or days. 128 Kbps is not fast enough to effectively run Web servers, unless the pages they host are text only and accessed by only a few outside users at a time. Multiple BRI lines can be aggregated, but this may not be as cost-effective as other alternatives.
PRI is a more expensive service that provides 23 data channels for a total data rate (using all channels) comparable to T-1 (plus one 64 Kbps data channel). The capacity can be reallocated at any time. That is, some channels can be used for voice when necessary then added back to the total data capacity when the voice calls are finished. The cost for PRI in many areas makes T-1 a more attractive alternative for Internet access. However, an advantage of ISDN over T-1 is that because it is not a point-to-point dedicated connection, it’s easier to switch between ISPs.
Many options, lower costs
Small and medium size businesses have many more options for connecting to the Internet today than just a few years ago, and costs for most connectivity types continue to come down. In deciding which choice is the best option for your business, you should consider performance (speed), reliability, latency, and terms of service, as well as initial cost of equipment and monthly service charges. There is no one-size-fits-all solution that’s right for everyone; each organization must consider the needs of its users, the technical expertise of its IT personnel, and the bottom line on its budget before making a decision.
Debra Littlejohn Shinder, MCSE, MVP is a technology consultant, trainer, and writer who has authored a number of books on computer operating systems, networking, and security. Deb is a tech editor, developmental editor, and contributor to over 20 additional books on subjects such as the Windows 2000 and Windows 2003 MCSE exams, CompTIA Security+ exam, and TruSecure's ICSA certification.