MNP-10 explanations, discussions, and beyond. NOTE: This file includes information collected and condensed from many sources. Supra's sole intent in providing this file is to inform user's of what MNP-10 is and what it is not. MNP10.TXT Rev 1.0 (PHM 6/2/93) from Supra BBS (503)967-2444 Supra's Technical Support department has been contacted by many users either confused or curious about the MNP-10 protocol and what it is able to do for them. The information provided in this file should assist modem user's in grasping an unbiased view of MNP-10's benefits and shortcomings. A brief look into CDPD is also provided at the end of this document to put MNP-10 into a more precise light in regard to other available advanced protocols. ********* MNP10 ********** Condensed Supra's CompuServe Area (Fm: Stephen Satchell 70007,3351) First, MNP-10 is also known as ACE, or Adverse Channel Enhancement. If the communication channel or connection changes characteristics significantly, the protocol will rebuild the data connection, possibly changing modulation methods in order to effect the repair. So a connection running V.32 modulation might, when something really hash happens on the line, might be recovered by reverting to a 2400-bps V.22 bis connection. Also, if the connection starts out bad and gets better, ACE will increase the speed until you reach the maximum practical speed for the channel you have. That's what it does. Note that ACE reacts to CHANNEL CHANGES. While this used to be a problem on the Public Switched Telephone Network (PSTN) the widespread installing of digital transmission means that changes don't happen because of the inter-exchange network. Local networks are also going digital, so the changes during a call simply don't happen. (This also negates the reason for having fall-forward and fallback in V.32 bis.) "So MNP-10 becomes a useless appendage for wireline calls. Cellular calls are another story, since each second can bring a whole new connection..." **** Citation: Newsbytes, Dec 11, 1992 pNEW12110013 ------------------------------------------------------------------------------ Title: Microcom maintains MNP 10 works best for cellular. (Microcom Inc.'s MNP 10 error correction system for cellular networks) Authors: Blankenhorn, Dana ------------------------------------------------------------------------------ Reference #: A13083837 ============================================================================== Full Text COPYRIGHT Newsbytes Inc. 1992 ..omitted.. Spokesman David Powers told Newsbytes that a number of US companies are also looking at MNP 10, in the same way as Bell Canada, and his company will soon name names. He also discussed why the system is preferable to V.42, the wired standard for error correction and compression at 9,600 bits/second, and V.42bis, which extends the same system up to 14,400 bits/second. "The advantage of MNP 10 over V.42 is fundamental," he said. "It can set-up a call, or perform the handshake, at 1200 bits/second upgrade the speed to 14,400, stay at that level as the connection allows, downgrade to slower speeds as conditions become noisy, and then unlike other schemes, upgrade the speed again. Most other modems will downgrade in a noisy environment, then stay there for the duration. MNP 10 gives you the most efficient transmission possible." ..omitted.. **** Citation: Newsbytes, Dec 10, 1992 pNEW12100017 ------------------------------------------------------------------------------ Title: Bell Canada launches MNP-10 trial on cellular net. (three-month trial of data transmission protocol) Authors: Buckler, Grant ------------------------------------------------------------------------------ Reference #: A13088059 ============================================================================== Full Text COPYRIGHT Newsbytes Inc. 1992 ..omitted.. Introduced at the beginning of 1991, MNP-10 is a data transmission protocol designed to minimize errors while getting the best possible performance out of modems, according to Microcom. Its key feature is the ability not only to slow down to a lower transmission speed when line quality is poor, but to speed up again if the connection improves. Most modems will slow down in response to a poor connection, but cannot resume a higher speed. The ability to shift speed both up and down makes MNP-10 well suited to cellular transmission, where the quality of a connection may vary as the mobile unit moves around. MNP-10 can also cope with the glitches caused as the cellular system "hands- off" calls from one cellular transceiver to the next, Powers said. ..omitted.. **** Citation: MacWEEK, Jan 27, 1992 v6 n4 p18(1) ------------------------------------------------------------------------------ Title: Data, voice go on air with combo. (Mitsubishi International Corp. and Microcom Inc. to co-market Cellular Data Link cellular telephone with built-in modem) (Gateways) (Product Announcement) Authors: Welch, Nathalie ------------------------------------------------------------------------------ Subjects: Product Introduction; Marketing Agreements; Telephones; Modems Integrated Voice/Data Companies: Mitsubishi International Corp._Marketing Microcom Inc. (Norwood, Massachusetts)_Marketing Products: Microcom MNP-10 (Modem)_Marketing Microcom Cellular Data Link (Cellular communications equipment)_Product introduction Reference #: A11884117 ============================================================================== Full Text COPYRIGHT Coastal Associates Publishing L.P. 1992 ..omitted.. MNP 10's Adverse Channel Enhancements regulate modulation and data packet size to optimize throughput across the poor quality connections frequently experienced with cellular systems. ..omitted.. **** Citation: MacWEEK, March 8, 1993 v7 n10 p18(1) ------------------------------------------------------------------------------ Title: Rockwell adds MNP Level 10 to chip sets. (Rockwell International Corp.) (MNP 10 adverse-channel protocol) (Gateways: Briefs) (Brief Article) ------------------------------------------------------------------------------ Subjects: Enhancements; Chip Sets; Cooperative Agreements; Protocol Companies: Rockwell International Corp._Product enhancement Microcom Inc. (Norwood, Massachusetts)_Product development Reference #: A13497616 ============================================================================== Full Text COPYRIGHT Coastal Associates Publishing L.P. 1993 Rockwell adds MNP Level 10 to chip sets Newport Beach, Calif. - Rockwell International Corp. last month began offering MNP Level 10 as a standard feature in all its high-speed V.32 and V.32bis data, fax and voice chip sets. Rockwell chips form the technology base for many third-party modems. MNP 10, called an adverse-channel protocol, enhances modem communications over cellular links and poor-quality land lines. Rockwell previously offered the protocol as a standard feature in its V.22bis devices and as an option in its V.32 and V.32bis products. In addition, Microcom Inc. of Norwood, Mass., the developer of MNP Level 10, and Rockwell have agreed to develop protocol extensions for new modem technologies, such as adaptive line probing, which are anticipated to result from the creation of the V.Fast standard in late 1993. Rockwell International Corp.'s Digital Communications Division is at 4311 Jamboree Road, P.O. Box C, Newport Beach, Calif. 92658-8902. Phone (714) 833-4600; fax (714) 833-4078. **** Citation: MacWEEK, Sept 10, 1991 v5 n30 p24(1) ------------------------------------------------------------------------------ Title: Microcom ships first Mac MNP 10 modem. (Microcom Inc.'s QX/4232bis 14.4K-bps data modem uses the company's MNP 10 error-correcting protocol)(includes a related article on Microcom's role in setting modem standards) (product announcement) Authors: Wylie, Margie ------------------------------------------------------------------------------ Subjects: Product Introduction; Modems; Error-Correcting Codes; Protocol Transmission Speed; Enhancements; New Technique Companies: Microcom Inc. (Norwood, Massachusetts)_Product introduction Products: Microcom QX/4232bis (Modem)_Product introduction Reference #: A11278095 ============================================================================== Full Text COPYRIGHT Coastal Associates Publishing L.P. 1991 By Margie Wylie Norwood, Mass. -- Microcom Inc. earlier this month announced and shipped the first Mac-compatible modem to use the company's super error-correcting protocol, MNP 10. The $999 QX/4232bis is a 14.4-Kbps data modem that uses public standard V.32bis and V.42bis data-compression protocols to speed transmissions to up to 38.4 Kbps. Using Microcom's latest error-correction protocol, MNP 10, the modem is designed to overcome the harsh telephone-line conditions of overseas calls or even cellular connections, according to Microcom. The error-correcting protocol will automatically speed up or slow down data transmissions as connection conditions fluctuate (see story, below). Like all modems that use specialized compression or error- correction protocols, the MNP 10 modem requires a connection with another MNP 10 modem to take full advantage of the higher speeds, throughput and reliability offered by the protocol. It will, however, communicate with any modem that uses the V.42bis protocol, according to Microcom. The QX/4232bis is not the first MNP 10 modem, but it is the first external modem that works with Macs and IBM PCs and compatibles. Newport Beach, Calif.-based Rockwell International Corp. earlier this year shipped an internal modem with MNP 10 for PCs. Microcom Inc. is at 500 River Ridge Drive, Norwood, Mass. 02062-5028. Phone (617) 551-1000; fax (617) 551-1007. If you've ever wondered what the alphabet soup of standards surrounding modems is all about, just ask Microcom. The company began developing the now ubiquitous MNP (Microcom Network Protocol) modem standards nearly 10 years ago. Now, it mingles its technology with public standards while continuing to develop higher-level services. MNP levels 1 through 4, error-correction protocols, are now part of the public domain and have been integrated into the Consultative Committee International Telegraph and Telephone's V.42 modem standard. The standards boost a modem's throughput to up to 38.4 Kbps. MNP 5 through 7 provide data compression and are compatible with the CCITT standard V.42bis. MNP 6, 9 and 10 offer "extended services" that build on the lower-level standards. MNP 10, the most sophisticated of the standards yet, will adapt packet sizes and data speeds dynamically to accommodate fluctuating line conditions that would break other modem connections. FROM A LONG ARTICLE ON MODEM STANDARDS: Lousy Connections While MNP 2-4 amounts to little more than a frill, a newer MNP error-control protocol called MNP 10 is well worth having if you send data by cellular or other very poor connections. Of course, the modems at both ends of the connection must support MNP 10. MNP 10 has four components, the first two of which are modifications of standard CCITT handshake operations. The first--negotiated speed upshift--attempts to establish a connection at the modem's slowest speed and moves higher until the highest reliable speed is found. This virtually guarantees that a connection will be established. CCITT handshakes do the reverse, sometimes making it impossible to make a connection in the first place. The second--robust auto reliable--makes multiple attempts to overcome channel interference during the handshake sequence before giving up. Once a connection is made, MNP 10 uses a technique called aggressive adaptive packet assembly to find the ideal data packet size--somewhere between 8 and 256 bytes. CCITT protocols start with the highest packet size and reduce it progressively, an inefficient process on a poor line. MNP 10 does the reverse. Finally, MNP 10's dynamic speed shift allows both modems to upshift or downshift the transmission rate as phone lines improve or deteriorate. CCITT V.32bis modems offer speed negotiation as well--but only when two V.32bis modems are involved. ********** CDPD ********** Condensed from Supra's CompuServe Area (Fm: Stephen Satchell 70007,3351) There is some discussion in the cellular community that the V-series protocols may not be suitable for cellular transmission. The CDPD (Cellular Digital Packet Data) people felt that pure QAM is not suitable for radio-based tranmission. They use a different protocol for the CDPD data, which permits 9600-bps operation over analog cell channels (full duplex) with some immunity to RF-based impairments and cellular-specific impairments. In particular, the modulation scheme would be "cell-switch aware" so that the data output could be clamped and data input stopped before a cell-switch occurred, and everything opened up again after the switch is completed. **** Citation: PC Magazine, Oct 27, 1992 v11 n18 p130(2) ------------------------------------------------------------------------------ Title: Lap lines: making connections with wired and wireless options. (Subnotebook Communications)(includes related article on pros and cons of different technologies) (Cover Story) Authors: Reiter, Alan A. ------------------------------------------------------------------------------ Subjects: Notebook Computers; Data Communications; Wireless Networks; Local Area Networks; Modems Reference #: A12746087 ============================================================================== Abstract: A variety of data communications options are available to users of the new generation of 'subnotebook' portable computers. Subnotebook computers do not have dedicated modem slots, instead using internal PCMCIA-slot modems or external modems connected to serial ports. Small external modems cost $150 to $500 and provide 2,400- to 14,400-bps communications; V.42 and V.42bis protocols are common for error control and data compression, along with MNP 5. Some new modems use cellular radio networks for wireless connections. Wireless data communications equipment remains bulky, expensive and less than reliable in many situations. Most of the US is covered by cellular service, but the modem must have an error-control protocol, and a cable for linking a standard modem to a cellular phone can cost as much as $300. Packet radio is an emerging wireless-communication technology that is available today and works better than cellular technology for short distances. Paging networks offer cost-effective one-way data communications and are small, inexpensive and require far less power than two-way systems. ============================================================================== Full Text COPYRIGHT Ziff-Davis Publishing Company 1992 Making connections with wired and wireless options. ..omitted.. Modems provide an alphabet soup of protocols, most notably V.42 error control and V.42bis data compression of up to 4 to 1, as well as the earlier MNP 5 data compression and error control scheme. Microcom (Norwood, Massachusetts; 617-551-1000) promotes its MNP 10 protocol as being specifically designed for communicating over cellular networks. If you intend to attempt cellular communications, hedge your bets and get a modem that handles V.42/V.42bis and MNP 10. To further complicate matters, an "enhanced" V.42 protocol incorporating most of the features of MNP 10 is under development, says Ken Krechmer, principal of Action Consulting, who specializes in telecommunications standards issues. ..omitted.. CELLULAR, PACKET RADIO If you want to send and receive data outside the office without a wired (phone) connection, you will be on the "bleeding" edge of technology: The equipment is bulky, balky, and expensive. Your choices today are cellular phones and packet radios. Cellular service covers much of the U.S. with varying degrees of reliability. To make the connection, you will need four pieces of hardware: your subnotebook computer, a modem, a thick interface cable, and a cellular phone. You'll get better coverage in remote areas with a bulky 3-watt in-car transportable phone than with a 0.6-watt portable unit. The modem needs an error-control protocol: V.42/V.42bis, Telebit PEP (Packetized Ensemble Protocol), or Microcom MNP 10. The cable can cost $300; it goes between the modem and phone and makes the modem think it's attached to a regular phone. The best-known is the Axsys cable, from Spectrum Information Technologies (Dallas, Texas; 214-630-9825). By next year, the smarts in the interface cables may be built into modems. With a good connection, it is possible to get throughput of 5,000 to 10,000 bps. Speed is important because connect time costs 20 to 50 cents a minute. The second form of ready-today wireless two-way communication outside the office is packet radio. For reliability and shorter messages such as dispatching applications, packet radio beats cellular hands down. Ardis, a partnership between IBM and Motorola, uses Motorola's over-the-air packet-radio protocol (Lincolnshire, Illinois; 708-913-1215). RAM Mobile Data, a business venture of RAM Broadcasting and BellSouth Enterprises, uses the Ericsson/Swedish Telecom Mobitex protocol (New York, New York; 212-373-1930). Typical bills on either network ranges from $40 to $120 per month. One of the most anticipated developments is the introduction of the Cellular Digital Packet Data (CDPD) service, developed by IBM and McCaw Cellular Communications. By overlaying packetdata techniques on today's analog cellular systems, data is supposed to be transmitted at 19,200 bps. CDPD is an important interim step between today's hit-and-miss analog cellular connections and the all-digital cellular network likely to become a commercial service (in a few areas only) in 1993. (New cellular phones will be both digital and analog, since the switch-over from analog service will take many years.) CDPD is a nonproprietary protocol that may be used by any cellular carrier when it becomes available in 1993. For CDPD, you will need to buy a special modem; these should be available in several versions, ranging from external portable devices to internal modems incorporated in cellular phones. ..omitted.. ********** End of File **********