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- Path: news.cfa.org!news
- From: bpiersel@brookings.itctel.com (Brian Piersel)
- Newsgroups: comp.dcom.modems
- Subject: Re: Actual Data Transfer Rates??
- Date: Sun, 24 Mar 1996 01:40:30 GMT
- Organization: Communicating for America Network Services
- Message-ID: <3154a55c.28033668@news.cfa.org>
- References: <4incqn$87h@babylon.fcl.net>
- Reply-To: bpiersel@itctel.com
- NNTP-Posting-Host: brookings-4.dialup.itctel.com
- X-Newsreader: Forte Agent .99d/32.182
-
- On Tue, 19 Mar 1996 22:34:48 GMT, ian@thenet.co.uk (Ian Leigh) wrote:
-
- >Just a quick one about the modem speed displays that appear such as
- >system monitor for Win95 or on an FTP program. When downloading I
- >quite often get a speed of 3.1 kbs even though my modem is only a 2.8
- >kbs model. Is there a reason for this?? Since it is normally zipped
-
- I assume you have a 28.8 kbit/sec modem, and if you divide that by 10
- bits/byte (1 start, 8 data, 1 stop), you get 2.88 kbytes/sec. However,
- when the modem is using an error-correction protocol, such as MNP or
- v.42, most of the framing bits are removed, and the average word
- length is close to 8 bits/byte. This works out to 3.6kbytes/sec. You
- lose some to the error-correction overhead, but you should still get
- speeds of 3.1kbytes/sec or higher on a good line.
-
-
- ------------------------------------------------------------------
- Brian Piersel Brookings, SD
- Internet: bpiersel@brookings.itctel.com CompuServe: 72723,321
- World Wide Web: http://ourworld.compuserve.com/homepages/BPiersel/
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