When I first started in the Internet business almost 14 years ago, there were 3 types of Internet access: woefully inadequate dialup, T1s and T3s (sometimes called DS3). Dialup, though relatively inexpensive, was slow. clunky and frustrating. T1s were, for the times, plenty fast enough but ridiculously expensive. T3′s, while blazing in speed, were so expensive that only Internet Service providers and very large companies could justify the expense.
Today, all of that has changed. There are so many flavors of high-speed Internet, ranging in price from $15 to upwards of $10,000, that for the average business, it is hard to figure out what is best for their application. Why, for example, would you go with a $300 SDSL connection when you can get ADSL for $25? Why does a 10Mb Verizon FIOS (fiber optics) connection cost only $50 when a partial T3 (also fiber optics) cost upwards of $2,000? Why would you choose one type of connection over the other?
Let’s see if we can make some sense of all this. Nowadays there are several different types of broadband, but they can be broken down into a few categories:
- High-speed copper
- Fiber Optics
There are some others, such as Internet over electric wires, but the four types listed above are by far the most prevalent. Let’s take a look a each category.
Typically, these types of connections, ADSL, SDSL, and T1s (sometimes called DS1), come into your business over phone lines, or copper pairs. They vary widely in data transfer rates (upload and download speeds) and reliability. ADSL and SDSL also vary widely in availability, based primarily on the location of your business.
ADSL stands for “asymmetric digital subscriber line.” By being asymmetric, it is “not symmetric.” In other words, it does not have the same upload and download speeds. ADSL connections typically have much higher download speeds, such as, say, 3.0Mbps down over 768Kbps up, which is 6 times faster on the download then the upload.
ADSL availability is dependant on location, or your business’s distance from the nearest local phone company central office. The further away you are from the central office, the lower the data transfer rate (and the reliability) of your DSL connection. In many areas, due primarily to distance, ADSL is not available at all.
ADSL speeds, determined by distance and price, vary widely — from 256Kbps/128Kbps to about 8Mbps/768Kbps. In some areas, ADSL2 is available, which increases both speed and distance specifications. ADSL2 supports speeds up to 12Mbps down over 1Mbps up, but the speed you will actually get depends, again, on your location.
ADSL is one of the cheapest Broadband options, comparable in price to cable. It is also one of the least reliable. Primary factors in reliability are the condition of the wiring and telecommunications infrastructure in your building and local area. Another important consideration is that most phone companies (they own the wiring and infrastructure) consider ADSL an entry level product and do not place a high priority on fixing problems when they arise.
ADSL can share an existing phone line, or a line with “dialtone,” or telephone service already on it. In fact, most phone companies, such as AT&T and Embarq, require dialtone on the line before they will provide DSL. Some companies, such as Verizon and Covad, offer dedicated (or naked) DSL, which is a copper pair with DSL and without dialtone.
SDSL stands for “symmetric digital subscriber line,” which is just the opposite of asymmetric digital subscriber line. SDSL has the same upload and download speeds. The trade off for the higher upload speeds is lower download speeds. SDSL speeds range from 128Kbps/128Kbps to 1.5Mbps/1.5Mbps, which are the same speeds available on a T1.
In fact, SDSL and T1s have a lot in common. The ISPs and phone companies that offer SDSL (and many don’t) consider SDSL a premium product, which means they get priority treatment when they have problems. For example, many phone companies have a 24-72 hour response time on problems on an ADSL line and a 4-8 hour response time on an SDSL line, making SDSL a better fit if your Internet connection is critical to your business.
However, in terms of availability and reliability, SDSL has many of the same limitations as ADSL. Your location, or distance from the local telco phone switching house, or central office, can not only determine whether you can get SDSL, but it can also affect reliability.
For a long time, prior to DSL and Cable, T1s were considered the gold standard in Internet connections. They were, however, very expensive. When I first started in the Internet business about 14 years ago, a full 1.5Mbps/1.5Mbps T1 ran well over $1,000. Today, if you shop around, you can get them for under $400. Considering, though, that the highest bandwidth you can get on T1 is 1.5Mbps, even at that price they are not that great a value.
That is, unless, your Internet application requires ultimate reliability. T1s are delivered on 2 copper pairs, rather than the single pair used for DSL connections. They are also terminated, both at the telco and the customer premisis equipment (CPE), with higher end hardware, making them more dependable. They are also available almost everywhere. The reason for this is that, because of the high price tag, the phone companies are more inclined to install repeaters (amplifiers) between the central office and the customer when distance becomes an issue.
However, in today’s data intensive world, 1.5Mbps is easy to saturate, or overload, especially when downloading from the Internet. The way many companies get around this is by “bonding,” or stacking multiple T1s. With the right CPE, T1s can easily be blended. Two T1s give you 3.0Mbps up and down, 3 T1s give 4.5Mbps, and so on. This can, however, become rather costly.
Cable broadband connections are delivered over the same cable as cable TV. And, no matter what Time Warner and all the other cable providers say in there ads, it is comparable in both price and performance to DSL. Performance and speed are highly dependent on the condition of the infrastructure in your area. However, distance does not affect reliability and availability nearly as much as with DSL. Speeds vary from provider to provider, but nowadays you can usually get up to about 12Mbps up or 1.0Mbps down.
Here are some of the caveats that come with cable. In order to get a decent price for Internet service from most cable providers, you also have to subscribe to their TV programming. In many areas office buildings and other business areas are not wired for cable, making it impossible or expensive to get. Also, cable networks in a given area are “shared” connections, meaning that everybody in your area all get bandwidth from the same source. Think of this as similar to a water main in a neighborhood where smaller lines branch off of a main line to feed each house or business. In areas where there are lot of heavy cable Internet users, this can affect the performance at your business. DSL, on the other hand, is a dedicated line between you and your ISP. What other users in your area do with their Internet service should not affect the performance of your connection.
For the longest time, fiber optics Internet connections, such as T3s, OC3s, OC12s, OC48s, and so on, were the only fiber Internet connections available. They were so expensive and costly to install, that only ISPs and very big companies could afford or justify spending the money on them. For example, when I first started in the Internet business a full 45Mbps T3 cost about $20K per month. Installation took several months and, depending on your location, could cost several thousand dollars.
Today there are several flavors of fiber optics connections, and they can range from $30 to upwards of $20K, depending on type and bandwidth. The three most prevalent types of fiber connections are: T3s and OCXs, Ethernet over fiber and fiber to the premise (FTTP).
T3s and OCxs
These are actually the same product. A T3 is actually an OC1. For example, you can get 3 45Mbps T3s from and OC3. OC stands for “Optical Carrier”, which is carried on a SONET fiber optic network. While not nearly as expensive as they used to be, they are still pretty costly. Depending on your location, a full 45Mbps T3 cost between $3K and $5K.
Most businesses would not order one of these products unless they had a need for sustained high Internet volume. Not only are the connections themselves costly, but the equipment, or CPE, required to terminate these types of connections is also pretty expensive. Typical users of this kind of broadband are ISPs, VoIP providers, hospitals, and busy medical imaging centers.
Ethernet over fiber
This product is similar to OCx connections in both price and delivery. The primary difference is that it comes in 100Mbps and 1Gbps slices, rather than 45Mbps. Another difference is that since it is delivered over a standard Ethernet wire, almost any router can terminate it, eliminating the need for expensive add-on cards typically required to terminate T3s and OCx connections. Again, you really have to have a need for a lot of sustained bandwidth to justify the expense of this type of Internet connection.
Another difference between Ethernet over Fiber and OCx connections is that that the latter are usually only provided by telephone companies, or by ISPs who lease telco company lines. Ethernet over Fiber is also being provided in many areas nowadays by cable companies, such as Time Warner.
Fiber to the Premise (FTTP)
This is a relatively new consumer-grade fiber product being offered by major phone companies, such as AT&T and Verizon. It is, in essence, their response to competition from the cable companies. Not only does FTTP provide low-cost Internet connections, but also TV programming and digital phone service.
As I write this, FTTP is still not available in most areas, though the phone companies are rolling it out at a pretty good clip. While it is a great way to get a lot of bandwidth inexpensively — up to 100Mbps down — it is fraught with some of the same issues as DSL and is not the best product for mission critical Internet connections. Typically, FTTP connections are asymmetric and cheap. You can, in some areas, get a 10Mbps over 2Mbps connection for as low as $25. However, since it is so cheap, it is not treated as a premium product and doesn’t have the same repair response times as higher end fiber connections.
In addition, since it is expensive to deploy, it will be some time before it is available everywhere, especially in rural areas. In fact, some areas, as with DSL, may never see it. The phone companies have a way of doing what is best for them, regardless of government regulation. See this article to see how this product was supposed to deployed: http://commtechwatch.com/?p=24
When most people think of wireless Internet, they think of the wireless LAN in their home or office. Wireless broadband is not the same thing. Your wireless router allows you to connect your laptops and computers to the Internet, but the actual Internet connection itself is usually wired, or one of the types of connections discussed in this article so far.
Nowadays, wireless broadband comes in several different flavors and can come in speeds from mediocre to blazing. In many cases, the true benefit of wireless connections is that they bypass expensive telco infrastructure to the customer premises, or “the last mile.,” making them less expensive. In almost all other types of Internet connections, the big phone or cable companies get the lion’s share of the money, no matter who provides the Internet service.
While there are several types of wireless connections, and the different types keeps growing, the 3 most prevalent are: cellular, satellite, and fixed wireless.
I can’t tell you how many times ISPs get call from laptop owners who want service they can use anywhere, but it happens often. You know, whip out your laptop and hop onto the Net. Nowadays, the only way to do that is with a cellular laptop card and cellular Internet service from a cellular provider, at a cost ranging between about $50 and $100 per month. Speeds, somewhere between 384Kbps/128Kbps to 1.5Mbps/1.0Mbps, depending on where you are, can be pretty dismal, making it virtually unusable for many applications.
While this technology is improving all the time (the new 3G cellular network offered by most major carriers is a prime example), it is no way ready for mission critical applications. Think about the reliability of your cellphone and this will give you a good idea of well your cellular Internet connection will work. Not bad, but not great, either. It’s good, though, for downloading your email on the road or downloading a file in a pinch.
Offered by the major satellite TV carriers, such as DirecTV and Dish, this is by far the most unreliable and, in some ways, useless Internet service available. it’s only saving grace is that it is available almost everywhere, a last resort for businesses that can’t get any other kind of service. Speeds are relatively slow (typically no higher than 300Kbps up), latency is high, and it is more expensive than DSL and cable. And, if you don’t want the TV service, standalone Internet service over satellite can be very expensive.
The biggest problem with this type of connection is latency, or “ping times“. Since the satellites are so far away, it just takes the data too long to get from the Internet to the satellite and back to your computer. This makes the service unusable for many business applications, such and virtual private networks (VPNs) and VoIP.
But, again, if it is all you can get, it beats dialup.
Fixed wirelessis a “line of sight” technology, meaning that the antennas involved have to see each other in order for the Internet service to be broadcast. A typical configuration is antennas on a mountain top beaming Internet service into a specific area, such as a city. Another application is to beam the service from building to building. In either case, there has to be a clear line of sight. When there is, the data transfer rates, depending on the equipment, can be impressive, as much as a gigabit or more.
Fixed wireless Internet, where available, tends to cost considerably less than service provided wired providers, because the telco or cable companies are not involved in delivering the service to the customer. There is, however, usually an upfront installation cost to cover the the radios and antennas. While this technology had a reputation of being unreliable, advancements have brought it along way. It is not as reliable as fiber optics, for example, but close.
William Harrel – www.williamharrel.com