Bandwidth is something your organization uses on a daily basis. Like most of the finer things in life, it is usually not noticed until it is gone. This short discussion of bandwidth will include a working definition, a "how to" approach on evaluating your business’s need for speed, and an overview of some cost-effective telecommunication options.
What Is It?
Our first goal should be to obtain what might best be deemed a standard industry definition of what bandwidth is and how it can be increased. The term "bandwidth" refers to the amount of data, usually measured in bits-per-second, that can be sent through a dedicated (leased) transmission circuit. In other words, "How much stuff you can send through a connection..." as colleague likes to say. A fast modem can move about 15,000 bits in one second; full-motion, and full-screen video would require roughly 10,000,000 bits-per-second, depending on compression. Although this may be a bit optimistic, in practical terms a one-page text document can, all things considered, be transmitted in about one minute over a fast modem connection.
In short, when one speaks of bandwidth it is a reference to the size and speed of a data circuit - or the ability of any network connection to move data, and at what relative speed. To increase bandwidth, you can do one of two things:
You can buy all the latest and greatest techie toys and tools simply because you can; or,
You can buy only what you need today and plan to upgrade as your company and desired network function grows.
I would encourage you to take the latter (and higher) road, which involves a detailed and well-documented technical approach. Although it is a somewhat technical exercise, determining your business’s "need for speed" does not need to be an intimidating undertaking. It should be viewed as a very practical venture.
How Much Speed do you Need?
As we walk through this "how to" approach in evaluating your company’s need for speed, try not to take any of the elements for granted. These points need to be investigated as you define your communication needs. It is important that, before you begin to shop for system hardware, software and connectivity options that you put together a requirements document that expresses your needs based on your company’s goals for a system. There are many great software packages, lots of fancy hardware and multiple ways to communicate (designed to go faster and faster) out there on the market. However, you want to measure the vendor’s product against your desired results, not flashy interfaces and pretty pictures. If you will take the time to document the answers to the following questions you will be well on your way to having a blueprint showing where your company is technically and where you want the network to be in terms of network functionality and faster processing or bandwidth. You will be able to speak with vendors and understand their product within the context of your needs.
Whether you have a network today or not, the project of determining your organization’s bandwidth needs involves the same foundational questions worthy of your company’s consideration. As you evaluate your current Information Technology and network effectiveness in terms of bandwidth, you may ask: How many users are in your organization? How will your people access the system? Is your system running on a LAN (local area network) or WAN (wide area network)? Is your office a stand-alone office utilizing a local area network or is your office one of multiple offices in your organization utilizing a wide area network? How do you access your system? Do you connect via in-house connectivity (Ethernet, etc.)? Or do you utilize a wide area network approach via remote dial in connectivity, twenty-four seven WAN connectivity, such as tacked up ISDN lines, dedicated circuits, or Internet connectivity? After collecting this data, you can determine how you are communicating today and how to look for ways to "bring on the bandwidth."
What are your Options?
It is important not to fall into the trap of thinking that one type of bandwidth technology is best for your organization. Although claims of super speed abound for some typologies, do your homework! Document, test, and evaluate your communication needs. Note: One does not need to choose between connection types in order to arrive at the most bandwidth for the cost. Many technologies can work well together and complement each other for big bandwidth at a lower overall cost model. Our company utilizes both ISDN and Frame Relay circuits on our network. (See Glossary for definitions.) We use ISDN technology when and where local call pricing and non-metered services are offered, and we use Frame Relay when ISDN is not cost effective, in those areas where long distance charges and metered services come into play. Fortunately, we have been able to create a pseudo "hub-ring" typology in our major markets in Texas by going with Frame Relay (256k pipes) to centralized offices and then ISDN (128k) to remote sites in that area. We are experimenting with Southwestern Bell’s version of xDSL, called ADSL, in the Austin area to the Internet and then to our Network via our T1 Internet connection to our ISP in the computer room. For smaller offices and remote connectivity, we also offer analog modem dial-up connections local and toll-free to Cisco 2500 routers.
There are various options on the market today to increase bandwidth. For example you may have a small office currently using a few PCs or terminals, some type of modem/router, and you may be sending a small amount of data across the wire. A dial-up solution (28.8 as mentioned above or up to 56k) may still be your best option. However, as analog lines generally cost fifty dollars per month, you might consider stepping up to an ISDN line for seventy-five dollars per month. (Note: Consult your local service providers, because mileage and markets vary; these price quotes may not apply in your area.)
The advantages of ISDN are dependent upon the local telephone/telecommunications company providers, latas, etc. In some markets and geographical areas you can "tack up" an ISDN line (leave the call placed 24/7) and bind the channels providing 128k. For little more than the cost of an analog line, you can in effect double your bandwidth. Beyond ISDN you might want to check out xDSL which claims a much faster stream of data at comparable cost models to ISDN. (Again, consult locally for prices in your market.) Note: ISDN and xDSL lines are often called dial-up connections as many companies and individuals use them for dial on demand calls or transmissions. Yet these circuits, in certain markets, can be tacked up thereby functioning as a dedicated circuit at a third of the cost of true dedicated circuits. When your communication needs exceed more bandwidth than 128k, dedicated circuits are the way to go. Generally speaking, dedicated circuits are more costly than dial-up connections; however, some would say they are also much more dependable. Our ISDN lines have proven themselves trustworthy and stable. Dedicated circuits do have their advantages, in that they offer at least the 56k bandwidth of a typical dial-up line and are scalable in the form of fractional T1s. Frame Relay circuits provide a very scalable approach to networking and can be monitored easily. They are also good for long hauls across latas and geographical areas.
Finally, bandwidth is utilized in all of these various connection types but is not limited to a discussion of just WAN environments. Taking the view that all data moves through any network connection at some speed or size, one realizes that bandwidth in its truest form is a part of the economy of both WAN and LAN networks. Many companies specialize in evaluating WANs and LANs or any combination thereof and would be glad to have the opportunity to evaluate your network.
However, if you have a technical support staff today you may need only a software package, basic hardware, or other monitoring tools in order to equip your folks to complete the project in house. Do not be intimidated by the process. Allow your local telephone/telecommunications company and other service providers to work with your support staff, if applicable. Together, they can perform evaluations of the communication lines or data circuits you currently utilize. Any telecommunication vendor worth its salt should be able to tell if you are within the limits of productive bandwidth. I would recommend increasing bandwidth if you are at 60 percent of your total available throughput. If you are maximizing your circuits, then it is time to upgrade to the next level of circuitry or size: Bring on the bandwidth!
For further Reading:
"The Internet Business Companion: Growing Your Business in the Electronic Age" by David Angel and Brent Heslop
"Swtiching Technology in the Local Network: From LAN to Switched LAN to Virtual LAN" by Mathais Hein and David Griffiths
"Maximum Bandwidth: A Serious Guide to High-Speed Networking" by Dan Blanharski
"Voice and Data Communications Handbook : Signature Edition" by B. J. Bates, Donald Gregory and Regis J. Bates.
ADSL--(Asymmetric Digital Subscriber Line)--A circuit that passes data over existing telephone lines. ADSL claims to be much faster than other types of connections, 1.544 megabits per-second with data speeds of 128 kilobits per second (requires a special modem or router).
ANALOG--Analog lines are commonly used for modem connections. The term analog refers to both the physical copper cable and the way data is transmitted over that cable through a local telephone company’s system switch. These switches can provide both voice and data communication. Note: Data over analog lines has limited transmission speed because of the narrow bandwidth of voice lines.
DEDICATED CIRCUIT--A circuit, usually called a "leased line," that connects two networks together via WAN routers and some type of WAN protocol for consistent data flow and network access. A 56K circuit offers the bandwidth of a single channel ISDN call.
DIGITAL--When the same analog data is converted to digital data, via a digital switch, it can be transmitted over digital signals faster and without much distortion. Digital data is more precise, but does not have the transmit range of analog.
ETHERNET--One method and cabling type used to connect PCs, printers and/or terminals together with a File Server or Main Frame.
FRAME RELAY--A high bandwidth data circuit service or protocol connecting two networks across some type of dedicated circuit in scalable bandwidth portions to end users (requires a router).
"HUB-RING"--A term used to describe a networking concept where one office serves as a hub, or central point of contact, for other surrounding or remote sites.
ISDN--(Integrated Services Digital Network)--Like a modem line, but offering much more bandwidth, a digital dial-up circuit capable of 56K per channel--these channels can be bound for up to 128K speed (requires a special modem or router).
LAN--(Local Area Network)--A network that restricts its user-base to those located ONLY in the same physical location, floor or building.
LATA--(Local Area & Transport Access) --A telephone company’s geographical boundary of service, where dial-up calls are usually free.
ROUTER--A unit that allows two networks to be "routed" together by searching for a specific IP address across LANs and WANs and getting the data to specified locations.
T1--A leased line that offers a bundle of 56K circuits offering the bandwidth of 24 single channel ISDN circuits.
"TACKED UP"--A term used to describe a dial-up circuit, such as ISDN, that is used for dedicated connectivity. Placing a call to another network and leaving the call up twenty-four hours a day, seven days a week --for anytime connectivity (avoid per minute charges by staying within a specific LATA).
WAN--(Wide Area Network)--A network that allows those outside the physical location of the LAN to access the system using some type of dial up or dedicated circuit connectivity.
xDSL--A generic representation of some form or product based on DSL, such as ADSL seen above. Some companies offer IDSL (ISDN Digital Subscriber Line).
Ted Smith began at Centex Title and Insurance Operations’ network in 1996 as a Network Specialist and currently serves as the Network Project Manager. Prior to joining the Centex Title team, Ted served as a Data Communication Technician with Dal-Tile, a 230-site Frame Relay network, for several years. Ted is a graduate of Dallas Christian College and is currently juggling his career, family life, and graduate studies.