Datasync recognizes that Internet users are demanding more and more speed. One of the new technologies that is available is 56k technology. In order to provide the greatest breadth of service to its customers, Datasync has implemented 56k technology to a number of its dial-in locations.

The most recent technology in the 56k modem arena has been the release of the V.90 protocol. Before V.90 hit the market, X2 and k56flex were the two main competing protocols in the 56k world, restricting ISP's to only 50% of the 56k modem users. V.90 has now solved this problem by providing a set of standards that allows all 56k modem users to connect to their ISP's without having to worry about compatibility. The V.90 standard still has a few kinks to work out. Datasync uses the latest software that supports the V.90 protocol.

56k is not 56k

Under the most ideal conditions, the best connect speed that a 56k modem will achieve is 53k due to FCC regulations. To achieve this speed, many conditions must be met. The world of 56k is absolutely not perfect and can be impacted by many sources, as discussed later in this document.

56k is one way technology

56k provides an increase in DOWNLOAD speed as compared to standard analog modems. UPLOAD speed is no greater than that achieved with standard analog modems. Generally speaking, this means that your computer can receive (download) data at a much faster rate than it can transmit (upload). This is very important if your primary consideration for implementation of 56k is to improve the upload speed of files needed to maintain your web site or to exchange data files with another office located elsewhere on the Internet. If this is your primary requirement for added speed, then you should consider the use of an all digital service such as DSL, ISDN, Frame Relay, or T1. Therefore, 56k technology is most applicable where "browsing speed" or "surfing speed" or "download speed" is important.

56k technology requires cooperation from many sources, including your Internet Service Provider (Datasync), your local telephone company, the wiring in your home or office, and the modem manufacturer. Each of these can provide stumbling blocks from achieving speeds greater than 33.6k.

Your Internet Service Provider

To use 56k technology through your Internet Service Provider, you must use the same standard as your ISP. For Datasync, you can use a V.90 modem (Lucent or 3Com/USRobotics modem recommended). Also, since the use of this technology requires that your ISP invest in very expensive equipment with a DIGITAL interface, some dial-in locations may not accommodate 56k simply due to the economics, or the unavailability of the digital lines required from the phone company.

Your Local Phone Company

The phone lines from your home are called "analog" lines because they are meant mostly for voice communications. Your standard phone lines sometimes goes through an analog to digital conversion process as your phone call travels to its destination. To use 56k technology over your standard phone lines, the number of such analog-to-digital conversions must be limited to
only one. If the distance between your modem and your internet service provider is greater than 18,000 feet (not as the crow flies, but as the telephone pole route takes it), then your call must travel through one or more central office "switches" where such conversions take place.
Therefore, if your modem call must travel through more than one of these switches, there is a possibility that more than one conversion is taking place, making 56k communications unlikely.

Your Local Wiring

In addition, 56k technology is extremely noise intolerant. Any noise on the phone line, regardless of its source will hamper your ability to connect at 53k. Many people are connecting at 38k, 42k, 48, and a few lucky ones are connecting at 50-52k. Noise, even in the sub-hearing level, can interfere with your ability to connect at higher speeds.

Line impedance is also important and there is little you can do if this is a problem. If your local telephone cable goes past your home or office, there is a chance that the individual line that goes to your home or office does not terminate (end) at the pole outside. There is a good chance that the cable will go on for miles and miles with all that wire hanging on to your modem line. Under normal circumstances, the telephone company accounts for this, but there are numbers of occasions where this extra cable has caused many problems with high-speed modems. If you suspect that this may be a problem, the telephone company might be willing to terminate your line on the telephone pole outside your home or office. However, don't count on it.

Check right under your desk

You may find that noise and impedance matching problems are caused by simple problems with your phone line as it enters your home. Poor connections can be caused by faulty telephone jacks and connectors, poor terminations, or even bad telephone surge suppressors (you do use surge suppressors in this area, don't you?). If you suspect a faulty surge suppressor, bypass it
temporarily while you try to connect with your 56k modem. If you notice an increase in connect speed, then it's time to replace the surge suppressor. Datasync recommends that you always use a telephone surge suppressor to avoid lightning and line surge damage to your modem.

Your Modem Manufacturer

Modem manufacturers have implemented 56k technology in a number of different ways. Some have chosen hardware chips that do the work, some have chosen a "flash bios" technique, and yet some have chosen a purely software technique. Because of this, each modem manufacturer is in the best position to explain why their modem is unable to achieve a higher speed than 28.8k. Contacting their technical support staff will result in new initialization strings or "flash bios" upgrades, either of which could be the magic answer to achieving higher speeds. If you do contact your modem manufacturer you can tell them that your ISP (Datasync) uses the Lucent PM3 communications server for V.90 implementation.

Before You Buy . . . . . . . . . .

If you plan to purchase a new modem as a jump from 14.4k, or as a replacement for a faulty one, then it makes sense to buy one that has 56k capability simply because there is little difference in cost between a new 33.6k modem and a 56k modem. If, however, you are considering the purchase of a 56k modem in place of that 28.8k or 33.6k, then you should determine if 56k will work properly in your area. Don't invest in a new modem and don't throw away that 28.8k modem until you can be relatively assured of success.

Datasync has performed extensive tests in various areas around the coast and will happily provide the results of those tests. This data is not a guarantee. It is simply a guideline. In some cases, the test data shows a maximum connection with a 56k modem of 26.4k, yet a speed of 38k was possible when a new modem initialization string was implemented. Conversely, a reduction in speed may occur based on your specific location and the condition of the telephone wiring in your home or office.

Upgrading to the New Standard

While the ITU has indicated that a new standard will be released in late Spring, implementation by modem manufacturers will take some time. Software upgrades and "flash bios" upgrades will be the fastest way to upgrade applicable modems while some will require that the modem be returned for chip upgrades or replacements. Datasync will also require that it upgrade its present equipment to the new standard. As this task is completed, Datasync's customers will be notified of its availability. Datasync will continue to gather information on the 56k technology and will make it available to its subscribers in a timely manner within this document or on its "News" pages.

56K Modem Testing

Testing was conducted from the following locations dialing into our Biloxi POP using a notebook computer with a Zoom PCMCIA K56 card. These tests were conducted from Datasync offices and from the homes of Datasync Internet Service employees and the homes of some of their friends. This information is to give some idea of the success we have found connecting from various areas, and some areas that we were unable to connect from. It should be noted that the closer you are to the POP, the better the connections were, however, phone line quality as well as the BellSouth equipment you pass through all make a difference.

What is required at the client-side?

For K56flex modem operation, the client-side modem must be operating with K56flex v1.0 software or higher. In many cases this will mean that the client-side modem will require a flash upgrade and, in a small base of modems, a hardware exchange may be necessary.

To determine if a client-modem is K56flex operational, a user can place the modem in the command mode and communicate directly with the modem using the AT command syntax. To enter AT commands, you must attach your modem to a computer's serial port and enter commands directly from terminal emulation software such as Windows 95's HyperTerminal program. To use AT commands in terminal mode to verify software version, do the following:

1. Start your data communications program.
2. At the screen prompt type in ATi3 followed by a carriage return (or enter).
3. Note the modem's response on the computer screen.
4. If the modem responds with V1.0-56K_DLS (or higher), a K56flex modem connection is possible.
5. If the modem responds with an earlier version of software (such as V0.519-K56_DLS), please contact the modem vendor's web site for the latest firmware upgrade. (See section: How can I get my K56flex client modem upgraded?)

What kind of performance can you expect with K56flex?

With the PortMaster 3 and K56flex True Digital modem technology, ISPs in effect have a completely digital path to the telephone company trunk. The PortMaster 3 experiences none of the telephone line impairments generally associated with analog modems, and it can transmit data at the highest possible K56flex connect rates.

However, client K56flex modems have to operate with the traditional analog local loop which has been optimized for voice traffic. This optimization actually impedes data traffic, and client K56flex modems must now be responsible for compensating for the telco's human speech optimization of a voice call. Client K56flex modems must be intelligent enough to differentiate between the maximum signal levels (up to 255 discrete levels) of a K56flex connection, synchronize with the local telco switch, compensate for digital loss, determine if voice PADs are present, and handle whatever noise is present on the phone line. For all of these reasons, it is the client K56flex modem that ultimately determines the maximum downstream connect speed.

Because K56flex modems operate asymmetrically, users will generally see a downstream speed of 42-52Kbps and a maximum upstream of V.34 speeds. ISPs using Channelized T1 lines generally get a 2Kbps lower connect speed than ISPs who use ISDN PRI lines.

How can I get my K56flex client modem upgraded?

It is strongly recommended that you go directly to your modem manufacturer's web site to obtain the latest software image. Some of the most common modem vendor's web sites are listed below. At the web site, be sure to look for or search on K56flex flash updates. Make sure the flash is labeled version V1.0 or higher.

Best Data
http://www.bestdata.com/
Boca Research
http://www.bocaresearch.com/
Diamond
http://www.diamondmm.com/
Hayes
http://www.hayes.com/v90.html
Motorola
http://www.mot.com/MIMS/ISG/Products/modemsurfr56/software.html
XIRCOM
http://www.xircom.com/
Zoom
http://www.zoomtel.com/k56/k56-files.html

Which client modems are compatible with the PortMaster 3?

Livingston has tested for interoperability with the following list of modems. As more modems are tested we will update this list.