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HP 3000 Series Dual Host Configuration 302258 U I HP 2333A using multipoint protocol. This means that your customer can run either character mode or block mode and use most application systems offered by HP. Application subsystem support includes TDP, Slate, Inform, Dictionary, Report, Transact, MM, PM, DSG, and VPlus. As for cabling convenience, the 2333A connects to either a modem or the DSNlData Link. Terminals can be connected directly to the 2333A with the RS-232-C terminal cable. This configuration allows multiple connections through one controller, eliminating the need for daisy chaining. An optional capability that the 2333A offers is dual host support. That is, the 2333A can be connected to two communication channels (two different DSNIINP's). This allows the user to have the option of logging on to one of two different HP3000s or to have a backup system in case of any problems. This dual host configuration is configured according to the user's needs, and resides in nonvolatile memory in the 2333A. In addition to all of these features, the Multipoint Cluster Controller is manufactured by HP and is designed to support the 3000 and HP terminals. Your customers no longer need to purchase a non-HP statistical multiplexer to access their remote working environments; rather, they can purchase a multipoint solution including the 2333A. This is a total HP solution. The 2333A is supported on the 30010A INP for HP Series I1 and I11 and the 30020AlB INP for HP Series 3X, 4X, and 64. All configurations need multipoint software (32193A from IND). For more information consult the DSNIMTS and HP 2333A Sales Training Manual. Problem: How to ensure a high degree of data integrity for your remote site printing. Solution: The HP 2608s printer. The printing requirements of the remote site user can differ from those of the typical system user. Reliability and ease of use are important factors to both users; however, data integrity and recoverability becomes a more critical issue to the remote site user. Longer cables or modem connections allow greater opportunity for errors in - data transmission. For this reason, HP multipoint was chosen as the appropriate solution for remote printing using the new 2608s Line Printer. The 2608s multipoint solution includes cyclical redundancy check characters with each block of data sent to the printer to insure data integrity. If the printer detects an error or does not receive a part of the data block, the entire block is retransmitted until it is received. Another major benefit is recoverability in the event of a data transmission interruption. If there is a power failure, line problem, or paper jam, the 2608s retains information on the printer environment such as print mode, top-of-form, etc. when data transmission resumes the 2608s will execute a topof-form and begin printing from the last checkpoint (completed page) of a spooled file. A power failure and subsequent recovery can occur with no operator intervention and without having to reprint the entire spoolfile. The 2608s is supported on the 30010A INP for Series I1 and 111 and the 30020AlB for the Series 3X, 4X and 64. The configurations can be hardwired using DSNlData Link or remote using multipoint daisychaining. The 2608s printer and 262X terminals are identically configured, using the appropriate pods to either DSNIMTS configuration. Conclusion Your customer now has several alternatives available when configuring devices farther away from the 3000 systems than HP-IB or RS-232-C limitations. Convenience, data integrity, cost savings, application software compatibility and remote spooled printing all contribute to making a multipoint configuration in a very attractive solution for workstation configuration. Computer News OEM Ed~t~on January, 1983 15
HP 3000 Series For more information on this topic, the DSNIMTS Reference Manual (32193-90002), 2608s Reference Manual (02608-90915) and the 2333A Reference Manual (02333-90001) should be of assistance. Multipoint Performance Vs. Point-to-Point Performance Multipoint is different than pointto-point connections. The two major variables that differentiate the two solutions are: Cabling configurations Performance considerations By definition, point-to-point is one terminal connected to one computer port. This is a straightforward way of sending data. Direct transmission between the terminal and computer takes place without using any intermediate protocol. As data is entered into the terminal and the return key pressed, data is sent to the computer. Multipoint is defined as multiple device connections to a single line. Communication becomes a little more complex. Because multiple devices are connected to one line, a certain amount of bandwidth must be devoted to controlling access to the line by the various devices. This portion of the bandwidth is not available for transmitting data and constitutes multipoint overhead. This overhead utilizes approximately 33% of the multipoint line. This means that 66% of the multipoint line can be used for data transmission. In order to successfully predict the performance of devices on a multipoint line, it is necessary to compute the amount of data that is expected to be transferred to and from these devices. To do this, line speed and expected data transmission for the line are the two variables necessary. For specific details, refer to the DSNIMTS Sales Training Manual. 1 6 January 1983 Computer News OEM Edt~on The fact that point-to-point and multipoint protocols differ does not mean that user response times in both situations differ. Provided the multipoint configuration does not exceed the line saturation, multipoint users will see response times similar to the point-to-point users. DSNIData Link and Remote Daisy Chain are multipoint configurations must commonly seen today. With the advent of multipoint enhancements to include HP 2608s and HP 2333A support, new configurations will be arising and the question of performance (i.e., user response time) rears its head once more. Since both products are connected to a multipoint line, the same variables (amount of data and line speed) exist when determining line utilization and subsequent performance. HP 2333A and Multipoint - What Kind of Performance Can Be Expected The 2333A Multipoint Cluster Controller provides the user with a point-to-point operation in a multipoint environment. This is a key statement. Even though the 2333A allows a Term Type 10 terminal to be attached to a multipoint environment, to run either character or block mode, and be totally transparent to the user, it still uses multipoint protocol. For this reason, performance (response time) depends upon the configuration of devices, the polling sequence, the amount of data being transferred and the speed of the line. Provided data transmitted at any one time does not exceed the maximum multipoint line saturation, the user response will be that of a point-to-point configuration. The only time there may be some response time degradation is when the system processor is doing extensive 110 tasks (e.g. LISTF, SYS DUMP, TDP, SLATE, etc.). When this happens, the system processor is slower to read the data from the multipoint line; subsequently, af- fecting the multipoint user's response time. Keep in mind that this is true if the user is connected directly to a multipoint line or to a 2333A Multipoint Cluster Controller. The conclusion is: When configuring the 2333A into a multipoint environment, all the multipoint variables that affect performance must be considered. HP 2608s and Multipoint - What Kind of Performance Can Be Expected The HP 2608s connected via HP-IB runs optimally at 400 lpm using all upper and lower case characters. When connecting to a multipoint line, the 2608s throughput (lpm) is identical provided it is configured properly. This means that line speed, number of characters per printed line and number of connected devices are what determine printer throughput. To show how line speed affects printer throughput (lpm), the following test was performed. The 2608s was the only device connected to a DSNIData Link. The amount of data transmitted was constant (i.e., 132 upper case character length lines for 10 minutes). The baud rates tested were 4800,9600, and 19,200 bps. The results: As baud rate increased, so too did the printer throughput. The results differ when more devices are configured on the line. When this occurs, a priority scheme is introduced. Tests were performed where the 2608s was configured with three other terminals. This was a Daisy Chain configuration running at 9600 bps. The printer was configured as High (I), Normal (5) and Low (9) priorities while the terminals were configured at priority 5. The results: When there are multiple devices on the line, the higher assigned priority for the 2608S, the greater the Line Printer throughput (lpm). Pp3
Page 1 and 2: IntemationallJanuary, 1983 edition
Page 3 and 4: Management Topics a If Customer Mai
Page 5 and 6: Management Topics Credit to OEMs fo
Page 7 and 8: Computer Support Standard System Ma
Page 9 and 10: Computer Support Basic System Maint
Page 11 and 12: HP 250 Series Shipboard HP 250 Appl
Page 13 and 14: HP 1000 Series HP A900 s Added to D
Page 15: HP 3000 Series 262X 263X 264X Famil
Page 19 and 20: Introducing the HP 2627A Color Grap
Page 21 and 22: Terminals HP 2627A Ordering Informa
Page 23: Peripherals HP 2601Al2602A For thos

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