max@maxsun.lgc.com (Max Heffler) (08/13/90)
I am using an Apple IIGS with a Transwarp GA and a Telebit Trailblazer plus modem to connect to another telebit at the office. When the connection was made at 19200 baud on both ends, the Telebit responded with Fast Connect implying that I had a 19200 baud connection; however, the throughput I measured under kermit was only around 2400 Baud. Does anyone know how to transmit at a faster rate with kermit, or possibly some other comm. program? Thanx in advance... -- Max Heffler internet: max@lgc.com Landmark Graphics Corp. uucp: ..!uunet!lgc!max 333 Cypress Run, Suite 100 phone: (713) 579-4751 Houston, Texas 77094
toddpw@tybalt.caltech.edu (Todd P. Whitesel) (08/14/90)
max@maxsun.lgc.com (Max Heffler) writes: >I am using an Apple IIGS with a Transwarp GA and a Telebit Trailblazer plus >modem to connect to another telebit at the office. When the connection was >made at 19200 baud on both ends, the Telebit responded with Fast Connect >implying that I had a 19200 baud connection; however, the throughput I >measured under kermit was only around 2400 Baud. Does anyone know how to >transmit at a faster rate with kermit, or possibly some other comm. program? Kermit 3.86 can handle 9600 (through a Super Serial Card and through the GS's modem port) without too much trouble. I'd check your control panel settings -- make sure THEY are set to 19200. Todd Whitesel toddpw @ tybalt.caltech.edu
UD182050@NDSUVM1.BITNET (Mike Aos) (08/14/90)
In article <1990Aug13.135356.11691@lgc.com>, max@maxsun.lgc.com (Max Heffler) says: > >I am using an Apple IIGS with a Transwarp GA and a Telebit Trailblazer plus >modem to connect to another telebit at the office. When the connection was >made at 19200 baud on both ends, the Telebit responded with Fast Connect >implying that I had a 19200 baud connection; however, the throughput I >measured under kermit was only around 2400 Baud. Does anyone know how to >transmit at a faster rate with kermit, or possibly some other comm. program? >Thanx in advance... >-- >Max Heffler internet: max@lgc.com >Landmark Graphics Corp. uucp: ..!uunet!lgc!max >333 Cypress Run, Suite 100 phone: (713) 579-4751 >Houston, Texas 77094 I've been told it's a limitation of Kermit. On the remote kermit I tell it to set baud 2400 (default is 1200), and delay 0. It seems to speed things up a little, but not all that much. You might wanna try optimizing any options for your particular set-up. (I'm only at 2400, but throughput is a lot less). ------- Mike UD182050@NDSUVM1 (.Bitnet?) "Share and Enjoy" UD182050@VM1.NoDak.Edu -Sirius Cybernetics Corporation Apple IIgs 'till I can afford a NeXT! I got LOTSA opinions. You want one? You can have it!
shatara@islnds.enet.dec.com (Chris Shatara) (08/14/90)
In article <1990Aug13.212155.29044@laguna.ccsf.caltech.edu>, toddpw@tybalt.caltech.edu (Todd P. Whitesel) writes... >max@maxsun.lgc.com (Max Heffler) writes: > > >Kermit 3.86 can handle 9600 (through a Super Serial Card and through the GS's >modem port) without too much trouble. I'd check your control panel settings -- >make sure THEY are set to 19200. > I've used kermit 3.86 at 19200 to transfer files between an MSDOS machine and MY GS Using a null modem cable for quite some time. Check the control panel settings. Also you should set the send/recive packet lengths to $FA as this is the largest packet that V3.86 will hanlde. You see an improvement in the equivalent transmission rate (fewer handshakes). /chris ============================================================================= | Chris Shatara | Internet: shatara@islnds.enet.dec.com| | Opinions expressed are | DEC Easynet: islnds::shatara | | mine and mine only! | UUCP: ...!decwrl!islnds!shatara | =============================================================================
gwyn@smoke.BRL.MIL (Doug Gwyn) (08/14/90)
In article <1990Aug13.212155.29044@laguna.ccsf.caltech.edu> toddpw@tybalt.caltech.edu (Todd P. Whitesel) writes: >max@maxsun.lgc.com (Max Heffler) writes: >>implying that I had a 19200 baud connection; however, the throughput I >>measured under kermit was only around 2400 Baud. >Kermit 3.86 can handle 9600 (through a Super Serial Card and through the GS's >modem port) without too much trouble. I'd check your control panel settings -- >make sure THEY are set to 19200. I think this misses an important point -- measured throughput cannot exceed the communication channel bit rate, but it certainly can fall far short of it. There are delays on both ends and, additionally, such high bit rates over voice-grade phone lines rely upon statistical compression techniques and half- duplex operation to attain apparent rates like 19.2Kbps. If the data does not fit the assumed statistical model, as compressed files would not, or if the communication protocol requires frequent turnaround for acknowledgment, as I think KERMIT does, then the so-called 19.2Kbps modem simply cannot provide 19.2Kbps apparent throughput. Such modems work best when sending a large amount of fairly patterned data in one direction, such as display characters for a display screen, or large blocks of data in a batched transfer protocol.
rond@pro-grouch.cts.com (Ron Dippold) (08/16/90)
In-Reply-To: message from max@maxsun.lgc.com > Connection was made at 19200 baud on both ends, the Telebit responded > with Fast Connect implying that I had a 19200 baud connection; > throughput I measured under kermit was only around 2400 Baud. You've got two problems: first, you need to use the FASTOPEN CDA to open the IIgs port up to greater than 9600 baud. The modem connects at 19200, but the path to the modem from the IIgs is only 9600. Second, kermit has lousy throughput. Your business computer should at least have a version of XMODEM. If you have YMODEM or ZMODEM, use those. ------------------------------------------------------------------------------ UUCP: crash!pro-grouch!rond | "Where knowledge ends, ARPA: crash!pro-grouch!rond@nosc.mil | Religion begins" INET: rond@pro-grouch.cts.com | - Benjamin Disraeli