iForm 56k Flex Guide


What you should know about K56Flex modems.
  • Although the modem is rated at 56Kbits, the highest connection speed you will achieve is 50Kb.
  • Connection speed is highly dependent upon phone line conditions at the time of dialing. Most callers connect in the range of 44-50Kb.
  • Phone line conditions may vary within the duration of the call, this may cause the modem to re-train and/or re-negotiate the connection speed. At these times the modem may stall for 10-30 seconds, but this should not be a frequent occurrence. Any modem (of any speed) will disconnect if the phone line experiences too much noise.
  • 56Kb is a maximum download speed, not the constant speed. Hence, download speeds will vary up to this speed according to net traffic and other network variables.
  • 56Kb technology is achieved by having a digital connection at the Internet Service Providers end, linking it to the public telephone system.This eliminates half of the Digital-Analog and Analog-Digital conversions that were previously needed between the users modem and the ISP, reducing quantization noise, lifting the theoretical line speed from 35Kb to 56Kb.
  • This has two important ramifications:
  • 56KFlex only supports User to ISP connections, NOT User to User connections. They will connect, but only at a maximum of 33Kb (V34).
  • Some people may NOT be able to connect at over 33Kb with their 56Kb modem if there is a telephone network Non-integrated RIM, Mux or PABX between them and their local telephone exchange. A call to Telstra may help in finding out if your telephone line can support a 56K connection. Otherwise, check first with the retailer if the modem can be returned (refund or credit) if you are unable to use it.
  • Finally, 56KFlex is an emerging technology, and the world standard for 56Kb is yet to be ratified (expected late 1998). Till then, modem consumers must be aware to make sure their modem contains the latest FirmWare release available. Having outdated FirmWare may result in lower connection speeds, and less reliable connections. Information on finding your FirmWare Version, getting the latest release and how to install it, can be obtained from the modem manufacturer or their web site. Very few modem retailers will be willing or able to offer support for 56K connection problems and will suggest the customer speak directly to themodem manufacturer. This is why it is important to purchase a well known, well supported brand that offers support and has an internet web site.
  • Modems that we know are currently working well with our digital interface are Netcomm 56 Roadsters (I & II), Banksia 56 modems.
  • If you currently have a Rockwell chipset based K56Flex modem and cannot find any support, and are experiencing intermittent disconnection problems, try the following suggestion:
    Put the string AT+MS=56,1,32000,4x000 in the Extra settings window of your modem properties, where x can be 0,2,4,6 or 8. This will limit your connection to that speed. We recommend you start with 40000 or 42000 and if successful over several adequately long connections, raise the speed by 2000 until problems restart, then drop back to the last successful setting. To find this window double-click My Computer, double-click ContolPanel, double-click Modems, select your modem and press Properties, select the Connection tab and press Advanced. After typing the AT command in (eg: AT+MS=56,1,32000,44000) press all the OK's till you close the Modem properties window.
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