RECOMMENDATIONS REPORT (Revised) for File Transfer Via PC Pursuit (Jan 03, 1989) Sprint Field Operations HQ Tech Support Reston, Virginia CONTENTS -------- PAGE ---- 1.0 Introduction........................................... 1 2.0 Recommendations........................................ 2 3.0 File Transfer Procedures............................... 5 4.0 Summary................................................ 6 5.0 Troubleshooting........................................ 7 SECTION 1.: Introduction ------- - ------------ Because of many customer complaints concerning PC Pursuit's inability to allow file transfers, Field Operations was requested to provide recommendations for file transfer via PC Pursuit. In compliance with this request, this document provides the following: * Recommendation on the best file transfer protocols to be used with PC Pursuit. * Recommendation on the hunt-confirm sequence and line parameters which provide optimum performance of various protocols. * The average transfer rates which can be expected using the correct hunt-confirm sequence and optional parameter settings. - 1 - SECTION 2.: Recommendations ------- - --------------- This section outlines the most common file transfer protocols used with PC Pursuit. The performance of the protocols in the direct con- nect and PC Pursuit environments are also indicated. The following protocols were tested via the Chicago in-dial to the Washington DC out-dial; the observations are summarized below. XMODEM PC Pursuit XMODEM file transfers performed at an average throughput of 34% when the correct hunt-confirm and terminal type was utilized. XMODEM does not support flow control, therefore it is suggested that the "relaxed" mode be invoked if the user's communications software permits this feature. YMODEM The performance of YMODEM file transfers VIA PC Pursuit was found to have an average throughput of 77% when the correct hunt confirm and terminal type is employed. Although YMODEM does not support flow control, it uses large 1024 byte packets which the network PAD handles quite readily under normal conditions. As a result, YMODEM is rated one of the faster protocols for file transfer via PC Pursuit. WXMODEM WXMODEM file transfers utilizing the correct hunt-confirm and terminal type performed well with an average transfer rate of 82%. This protocol is capable of handling flow control which enables it to perform with better reliability in the PC Pursuit environment. Users should be aware that an early version of PROCOMM is known to have a software problem which can affect the performance of WXMODEM file transfers. KERMIT An optimum average throughput of 65% was obtained by KERMIT file transfers via PC Pursuit. The throughput was obtained with a packet size of 90 and a window size of 31. KERMIT software which supports the sliding window feature performs with optimum efficiency in the PC Pursuit environment. - 2 - SEALINK SEALINK file transfers via PC Pursuit performed exceptionally well with an average throughput of 91% with the correct hunt-confirm and terminal type. SEALINK supports flow control and was specifically designed to operate in the networking environment. Some versions of SEALINK however, do not provide proper error recovery which could pose a problem for some users. ZMODEM File transfers utilizing ZMODEM protocol via PC Pursuit yielded an average transfer rate of 93%. ZMODEM performs well in the PC Pursuit environment at the default settings. Depending on the type of user equipment, ZMODEM options may need to be modified to permit optimum throughput. The ZMODEM command line used in our test configuration was simply as follows: Uploads: DSZ port 1 rz Downloads: DSZ port 1 sz The X.3 PAD parameters which provide optimum performance are 1:0,4:10,5:1, 7:8,12:1. In addition, flow control (XON/XOFF) should be enabled at the user PC and the host. It should be noted that in most cases these additional PAD parameters are optional and need only be employed if the user is experiencing difficulty transferring files via ZMODEM. The following page summarizes file transfer performance of the protocols tested. The protocols are listed in order (PCP best to worst) in two categories: 1) performance via direct connect, 2) per- formance via PC Pursuit utilizing the recommended hunt confirm and parameter settings shown. It should be noted that the optional parameters need only be employed if a user experiences problems with transferring a particular file. - 3 - SECTION 3.: File Transfer Procedures ------- - ------------------------ This section outlines the step by step procedure for executing file transfers via PC Pursuit. These procedures must be followed exactly to achieve optimum transfer rates. The optional X.3 parameters shown on the previous page indicates the parameters which provide the best transfer rates as well as reduce the possibility of aborts. STEP 1.: Set PC communications software to 8 bits, no parity, 1 stop bit, full duplex. At this time, the user may wish disable or enable local (XON/XOFF) flow control depending on the type of protocol to be used. STEP 2.: Dial local rotary with the communications software set at the desired speed. STEP 3.: Upon connect use the correct hunt confirm sequence: At 300/1200bps use - At 2400bps - <@ D CR> NOTE: "D" MUST BE UPPER CASE. STEP 4.: At prompt "TERMINAL = " enter and return. STEP 5.: At the "@" prompt enter the destination mnemonic, out-dial speed, ID and password. It is important that out-dial speed matches in-dial speed. DO NOT MIX IN-DIAL AND OUT-DIAL SPEEDS. STEP 6.: If OPTIONAL X.3 pad parameters are to be changed, do so at this point by entering <@ CR>. To set parameters as prescribed perform the following: To set parameters enter Example: SET 7:8,4:10,5:1,7:8,12:1 To read parameters enter Return to out-dial port by entering . STEP 7.: Upon connecting to the destination pad, ensure communication with the out-dial modem by entering . The destination modem will respond with "OK". STEP 8.: Enter and the local number you wish to dial. STEP 9.: Queue host file transfer and start file transfer. Please note that these are the basic steps needed to achieve success- ful file transfers. Since communications software may vary from package to package, additional steps may be needed to initiate the start of the file transfer at the user software level. - 5 - SECTION 4.: Summary ------- - ------- Extensive testing has resulted in identifying the expected performance of six file transfer protocols when used with PC Pursuit. These protocols have been determined to perform satisfactorily with PC Pursuit when the correct hunt-confirm, terminal type and parameters are employed. It is the recommendation of Field Operations that customers be in- formed of the correct logon procedures and the protocols which provide the most reliable file transfers. Customers should also be reminded that PCP users can expect a small degree of network delay which is considered a common characteristic of packet switched networks. In addition, users should also be informed that poor quality voice grade telephone lines can adversely affect file transfer sessions. Field Operations is one of many Sprint groups dedicated to providing customers with complete support for PC Pursuit. Field Operations will offer assistance with file transfer problems providing the customer is willing to release a copy of the problem software as well as provide the pertinent information necessary to resolve the problem. - 6 - SECTION 5.: Troubleshooting ------- - --------------- If you are experiencing trouble with PC Pursuit check the following items: * Verify the correct hunt-confirm sequence * Verify user software comm parameters are set to 8 bits, no parity and 1 stop bit. * If problems with file transfer only, try the optional ITI PAD parameters. If all else fails, then call Sprint Customer Service and report the problem. Be prepared to provide the following: * Type of communication software * Type of PC, make and model * Type of modem * Call origin (in-dial city) * Call destination (out-dial city) * Speed in * Speed out * Type of session * Time of failure * Date of failure * Point of failure in session * Out-dial number * Network Addresses (shown at login, and by command "STAT" when connected to out-dial port) Additional information may be required depending on the nature of the problem. - 7 - FILE TRANSFER PERFORMANCE STATISTICS General Communication Parameters = 8 bits 1 stop bit N no parity Terminal Type = D1 | PERFORMANCE STATISTICS DIRECT CONNECT | | | | | | XFR | | PROTOCOL SPEED SECONDS CPS BPS RATE | |======================================================| | | | ZMODEM UP 1200 ***394 114.36 1143.55 95% | | ZMODEM UP 2400 ***199 226.41 2264.12 94% | | ZMODEM DN 1200 ***394 114.36 1143.55 95% | | ZMODEM DN 2400 ***196 229.88 2298.78 96% | | | | SEALINK UP 1200 ***418 107.79 1077.89 90% | | SEALINK UP 2400 ***200 225.28 2252.80 94% | | SEALINK DN 1200 ***400 112.64 1126.40 94% | | SEALINK DN 2400 ***205 219.79 2197.85 92% | | | | WXMODEM UP 1200 ***405 111.25 1112.49 93% | | WXMODEM UP 2400 ***205 219.79 2197.85 92% | | WXMODEM DN 1200 **277 96.12 961.16 80% | | WXMODEM DN 2400 ***216 208.59 2085.93 87% | | | | YMODEM UP 1200 ***387 116.42 1164.24 97% | | YMODEM UP 2400 ***194 232.25 2322.47 97% | | YMODEM DN 1200 ***385 117.03 1170.29 98% | | YMODEM DN 2400 ***199 226.41 2264.12 94% | | | | KERMIT UP 1200 ***553 81.48 814.76 68% | | KERMIT UP 2400 ***287 156.99 1569.90 65% | | KERMIT DN 1200 ***571 78.91 789.07 66% | | KERMIT DN 2400 ***295 152.73 1527.32 64% | | | | XMODEM UP 1200 ***425 106.01 1060.14 88% | | XMODEM UP 2400 ***219 205.74 2057.35 86% | | XMODEM DN 1200 ***436 103.34 1033.39 86% | | XMODEM DN 2400 ***228 197.61 1976.14 82% | ======================================================= * Optional PAD parameters which optimize performance ** File size = 26624 *** File size = 45056 | PERFORMANCE STATISTICS VIA PCP | | | | HUNT OPTIONAL ITI | | XFR CONFIRM FLOW X.3 PAD | | PROTOCOL SPEED SECONDS CPS BPS RATE SEQUENCE CONTROL PARAMETERS NOTES | |====================================================================================================================| | | | ZMODEM UP 1200 ***399 112.92 1129.22 94% CR D CR XON/XOFF *1:0,4:10,5:1,7:8,12:1 *Host a terminal XON/XOFF | | ZMODEM UP 2400 ***200 225.28 2252.80 94% @ D CR XON/XOFF *1:0,4:10,5:1,7:8,12:1 *Host a terminal XON/XOFF | | ZMODEM DN 1200 ***398 113.21 1132.06 94% CR D CR XON/XOFF *1:0,4:10,5:1,7:8,12:1 *Host a terminal XON/XOFF | | ZMODEM DN 2400 ***204 220.86 2208.63 92% @ D CR XON/XOFF *1:0,4:10,5:1,7:8,12:1 *Host a terminal XON/XOFF | | | | SEALINK UP 1200 ***420 107.28 1072.76 89% CR D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | SEALINK UP 2400 ***202 223.05 2230.50 93% @ D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | SEALINK DN 1200 ***402 112.08 1120.80 93% CR D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | SEALINK DN 2400 ***207 217.66 2176.62 91% @ D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | | | WXMODEM UP 1200 ***406 110.98 1109.75 92% CR D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | WXMODEM UP 2400 ***263 171.32 1713.16 71% @ D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | WXMODEM DN 1200 ***469 96.07 960.68 80% CR D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | WXMODEM DN 2400 ***214 210.54 2105.42 88% @ D CR XON/XOFF *7:8,1:0 *Host a terminal XON/XOFF | | | | YMODEM UP 1200 ***467 96.48 964.80 80% CR D CR NONE *7:8,1:0 | | YMODEM UP 2400 ***252 178.79 1787.94 74% @ D CR NONE *7:8,1:0 | | YMODEM DN 1200 ***461 97.74 977.35 81% CR D CR NONE *7:8,1:0 | | YMODEM DN 2400 ***263 176.00 1760.00 73% @ D CR NONE *7:8,1:0 | | | | KERMIT UP 1200 ***558 80.75 807.46 67% CR D CR XON/XOFF *7:8,1:0 | | KERMIT UP 2400 ***285 158.09 1580.91 66% @ D CR XON/XOFF *7:8,1:0 | | KERMIT DN 1200 ***579 77.82 778.17 65% CR D CR XON/XOFF *7:8,1:0 | | KERMIT DN 2400 ***297 151.70 1517.04 63% @ D CR XON/XOFF *7:8,1:0 | | | | XMODEM UP 1200 ***985 45.74 457.42 38% CR D CR NONE *7:8,1:0 | | XMODEM UP 2400 ***636 70.84 708.43 30% @ D CR NONE *7:8,1:0 | | XMODEM DN 1200 ***1001 45.01 450.11 38% CR D CR NONE *7:8,1:0 | | XMODEM DN 2400 ***636 70.84 708.43 30% @ D CR NONE *7:8,1:0 | ====================================================================================================================== * Optional PAD parameters wich optimize performance ** File size = 26624 *** File size = 45056