[Image] [Image] --------------------------------------------------------------------------- Q. How does 56Kbps modem technology work? What makes it different from 28.8Kbps and 33.6Kbps technology? A. The basic concept behind this communications technology is that the public switched telephone network (PSTN) is increasingly a digital rather than analog network. Existing analog modems, such as V.34, "see" the PSTN as an analog system, even though the signals are digitized for communications throughout most of the network. Rockwell's 56Kbps technology looks at the PSTN as a digital network which just happens to have an "impaired" section represented by the copper wire connection between the central office and the user's home, usually referred to as the analog local loop. To make the technology work over that analog loop, it must "equalize" the line using special technology that converts the signal samples seen by the user's modem into the equivalent of what is being sent from the central office. More details are available in our white paper, which is available on our web site at http://www.nb.rockwell.com/mcd/K56Plus/56k_wp.html. Q. Is this new 56Kbps analog modem technology an extension of V.34 (28.8/33.6Kbps)? A. No, the techniques used in V.34 (28.8Kbps) have been exploited to their limits. This is a new technique where the network is viewed as a digital transmission medium and the data is encoded for transmission over the user's telephone line, also known as the analog local loop. Q. Can any two modems incorporating this technology connect at 56Kbps? A. Yes, if one is a central-site modem with a digital connection to the network. On the other hand, two end-user modems incorporating this technology will not connect using this technique. Furthermore, 56Kbps speeds can only be achieved on good line conditions. Q. Does 56Kbps technology have different applications than previous modems, then? A. 56Kbps technology will primarily be used for faster web browsing and Internet access, and for faster remote access to corporate LANs that digitally connect to the PSTN. Q. How can you receive data at 56Kbps when the theoretical Shannon's Limit is about 35 Kbps? A. Shannon's limit is theoretically determined by the impairments (noise) in the telephone link. This new technique relies on a reduced noise environment due to a digital connection to the network by the service provider and a new encoding technique. Q. Why hasn't this technology been developed before? A. Actually, the concept has been around for a number of years but it hasn't been practical because most modems installed at service providers used to use analog connections to interface to the network. Q. Is this new high-speed analog modem technology a compression algorithm or a modulation scheme? A. It is neither a compression algorithm nor a modulation scheme. Data is actually passed on the telephone line at 56Kbps. It is a technique for encoding data for transmission over the telephone line -- we prefer to refer to it as an encoding technique instead of a modulation scheme. Q. What's the difference between modulation and encoding schemes? A. In modulation, a carrier is modified so that it carries information. Ordinary modems modulate a carrier to carry digital data. In this new technique we encode the data. By "encoding," we mean that data is sent in digital form through the network, and encoded in such a manner that it can pass through the user's analog telephone link at a high rate. This is a very technical area which can best be understood by reading our white paper describing the technology. Q. Can you define this new product within the context of ISDN, frame relay, cable modems or ADSL? A. There are no relationships. In reference to all of these techniques, the advantage of this new technique is that it works over the existing switched telephone network. It does not require the telephone company to replace or add any new equipment. Q. What do you mean in your news release by "bridge the gap" between current analog transmission rates and fully digital communication? A. ISDN, which provides two 64Kbps channels, has not yet achieved a significant penetration in the home market. This 56Kbps technology will allow users to gain the speed advantages of almost one ISDN channel without having to order and pay for a new ISDN telephone line. Q. How will 56Kbps services compare in price to other digital services? A. This technology does not require new services. It will utilize the existing analog telephone service. Q. Can the 56Kbps technology go to even higher speeds? Under what circumstances? A. Theoretically, the technology can approach 64Kbps; however, there are a number of practical problems with achieving this speed including line noise, non-linear distortion, the quality of the network codec, and others. The industry is working to push the technology to its highest possible data rate, and rates near 64Kbps may be possible in the future. Q. Does the user need an additional phone line? A. No, this new technology will work over a single existing analog phone line. Q. Does the phone company need to install new equipment? A. No. The use of this technique will be transparent to existing phone company equipment. Q. Does the user need new equipment? A. The user must have a modem which implements this new technology. Q. Will it work on long-distance calls or only local calls? A. It will work on both local and long-distance calls, depending upon the network interconnection. See our white paper for more details. Q. What do the ISPs have to do for users to get 56Kbps Internet access and web-browsing speeds? A. Similar to end-users, the ISP must have equipment that includes modems which support this technique. Additionally, the ISP must utilize a digital connection to the network. This will be an extremely straightforward process for ISPs who are installing new central-site equipment featuring the new 56Kbps modems. However, ISPs who wish to upgrade existing central-site equipment to the new 56Kbps technology face two additional issues. First, ISPs will probably wish to use ISDN Primary Rate Interface (PRI) network connections rather than lower-performance T1 "robbed bit" interfaces. All other things being equal, users will be able to connect at a higher rate to an ISP utilizing ISDN PRI than to one utilizing a T1 "robbed bit" signaling. Many ISPs, therefore, will want to upgrade their network interface to ISDN PRI, as well as adding 56Kbps modem capability to their central-site equipment. Second, ISPs will need to make sure that their equipment provides adequate compression performance at 56Kbps operation. Without adequate compression performance, the "effective throughput" may not be much better than what users experienced at 28.8 Kbps or 33.6 Kbps. Some of the central-site modems which are being promoted as "upgradeable" to a 56Kbps encoding scheme may only have enough processing power to support adequate compression performance at 28.8Kbps and 33.6Kbps speeds. In these cases, users may not experience better throughput than when they were operating at 28.8Kbps or 33.6Kbps speeds. This is an especially insidious problem because it occurs at the central site, out of the control of the user. Even if the user has purchased a new 56 Kbps modem, the throughput may be limited by poor compression performance at the central site. See [Image] for the complete listing of modem manufacturers and Internet Service Providers (ISPs) supporting Rockwell K56Plus technology. Q. What exactly is "effective throughput?" Why is it so important to achieving full 56Kbps performance? A. It is important to first understand how modems work. Data is first sent into a modem, where it is compressed and sent over the telephone line to another modem, where it is then decompressed. The amount of data that can be sent into the modem and effectively transmitted to the other end is called the effective throughput. The level of compression that the modem's processing power can support affects the effective throughput. The better the compression, the higher the effective throughput. And the higher the effective throughput, the faster the Web pages will come up on the user's screen. Q. Will 56Kbps technology be backward-compatible with existing modems that are already installed? A. Products incorporating this new technology will also contain all previous modem modulations, including V.34, V.32bis, and facsimile modulations. During the initial stages of a connection the two modems will determine what modulation and at what speed the transmission will occur. Q. Why can't users get 56Kbps speed both sending and receiving? A. It is more difficult to equalize the upstream channel, and therefore more difficult to achieve the same high data rates as are achieved in the downstream channel. However, for Internet access, the data rate in the upstream direction is less important than downstream, since the upstream channel transmits mostly "key strokes and mouse clicks." At present, a data rate of around 30 Kbps can be attained in the upstream direction, but research continues toward increasing that rate. Q. Why can't all 56Kbps modems connect to each other, initially? What happens if a user with one manufacturers' 56Kbps modem tries to connect to a remote network or ISP that has another manufacturers' 56Kbps modem on the other end? A. Although it appears that most companies are using the same basic technique to achieve 56Kbps operation, the specific design choices are unlikely to be the same. However, if two modems are unable to connect at 56Kbps, they will drop down to a mutually interoperable industry-standard data rate like 28.8Kbps or 33.6Kbps. Rockwell is working with the appropriate standards bodies, toward the development of a ratified specification that will serve as a worldwide interoperability vehicle. Q. What is happening with the industry standards effort for 56Kbps modem technology? What standards organizations will be involved, if any, in addition to the ITU? A. The ITU sets international standards and thus would be the preferred standards body for this technology. On November 13, 1996, Rockwell Semiconductor Systems hosted the TR-30 Pulse Code Modulation (PCM) ad hoc group, the first standards meeting aimed at creating draft standards for PCM modem technology. These draft standards are being developed to ensure interoperability between 56Kbps products from a broad spectrum of modem vendors and other communications equipment suppliers. Rockwell was joined at the meeting by a number of leading U.S. PC and communications companies including Intel, Lucent, Hayes, Motorola, IBM, Compaq and Cisco. This ad hoc committee has been created under the direction of the Electronics Industry Association (EIA) and Telecommunications Industry Association (TIA) to develop an EIA/TIA interim standard for U.S. 56Kbps PCM modems by mid-1997. The TIA TR-30 group also will serve as the advisory committee to the U.S. government on modem-related issues involving the International Telecommunications Union (ITU). It is expected that the group's interim work in the U.S. will form the basis for a U.S. submission to the ITU for a worldwide standard for 56Kbps modem technology. Rockwell is a charter member of this TIA group and is the assistant editor for the draft standard, working with Motorola. Q. Why is interoperability so important to the success and adoption of 56Kbps modem technology? Will 56Kbps modem technology follow the same standards-development process as the previous 28.8Kbps and 33.6Kbps modem technology? Are there unique new interoperability issues that need be resolved before 56Kbps modem technology achieves its full potential, since this technology relies on the digital telephony infrastructure? A. Interoperability is critical to any modem technology. In the case of 56Kbps modems, the technology introduces new issues which may require slightly different handling by the industry standards bodies as compared to previous 28.8Kbps and 33.6Kbps efforts. Rockwell is working with a number of other leading PC, modem, and telecommunications equipment vendors to address these new issues which may impact the future success of 56Kbps modems. Also, Rockwell has joined with Lucent to announce that the two companies will make their 56Kbps modem chipsets interoperate at 56 Kbps. Agreements like this help to ensure that customers who purchase a modem that implements Rockwell's K56Plus will have the highest probability of achieving a connection at speeds up to 56Kbps. Q. Some people say that the first to market will achieve status as the de facto 56Kbps standard. Why isn't that true? Why does the industry need to wait for the standards bodies to determine specifications? A. The diffusion rate for a new modem technology like this will be slow, and it is critical that the industry develop worldwide standards. Early installations of 56Kbps will likely be "show POPs" rather than general deployment. Network operators will likely move slowly to avoid problems for their users. The issue of "which 56Kbps?" will disappear when there are standards. Rockwell is an active participant in the standards-development process, and is also working very closely with the central-site equipment suppliers who provide the critical ISP technology to make 56Kbps work. Q. What is the next step after the TIA/TR30 PCM Modem interim specifications are completed? A. Once the TIA PCM ad hoc committee develops its interim draft standard, for which Rockwell is the assistant editor, it will likely be submitted to the ITU. Modem manufacturers may choose to implement the TR30 interim standard until the ITU standard is achieved. Q. How long will that process take? A. The TIA PCM ad hoc committee has committed to finalizing a draft standard by mid-1997. The ITU standardization process could take another 12 to 15 months. Q. When can we see Rockwell's K56Plus? A. Rockwell will be demonstrating its K56Plus technology at COMDEX. Q. Why has Rockwell announced K56Plus before it's ready to ship? A. It takes time to educate people about this new technology, and for central-site equipment providers to incorporate the technology into their plans. This is not like traditional modem products that operate in an isolated environment -- 56Kbps technology is just one component of a large network infrastructure including both central-site and client-side modems. Rockwell announced early to help prepare the market for the final product and for its successful migration into customers' hands. Q. What will be the price premium of modems incorporating Rockwell's K56Plus technology over today's high-speed V.34 (33.6Kbps)modems? A. It is too early to know how modem manufacturers will price their products. However, it's likely that this new technology will follow the same price path as 28.8Kbps modems, which entered the market at retail prices in the mid $200 range, and quickly came down in price to under $100. Q. What customer support is there for Rockwell's K56Plus technology? A. Rockwell has already gained public support for its K56Plus technology from key central-site modem suppliers including Ascend, Cascade, Hayes, Microcom and Shiva, plus more than 100 leading client-modem manufacturers. These manufacturers support an installed base of more than 40 million modem users. See [Image] for the complete listing of modem manufacturers and Internet Service Providers (ISPs) supporting Rockwell K56Plus technology. Q. What modem experience has Rockwell applied to the development of its K56Plus technology? A. Rockwell has been a proven modem technology leader, and will continue to apply that knowledge base to our 56Kbps modems. The company has shipped more than 25 million high-speed modems for PC-based client subscriber applications in 1996 alone, and has extended its already well-established market leadership position of central site modem connection points. Rockwell also has experience in ATM, frame relay and other technologies needed to provide complete networking solutions. Q. What is Rockwell's current worldwide market share for modem products? A. According to market analysis by Dataquest and Rockwell, between January 1995 and March 1996, more than 70 percent of access concentrator ports, which contain a central-site modem, were based on Rockwell modem chipsets. Rockwell also supplies more than 50 percent of the worldwide modem products into remote modem applications. -------------------------------------- [Image] [Image][Image] [Image][Image][Image][Image] --------------------------------------------------------------------------- What's | Worldwide | Search | Technical | Company | Corporate New | Contacts | | Reference | Profile | site --------------------------------------------------------------------------- Copyright © 1996 Rockwell International, all rights reserved