


          System
          Support
          Addendum

          ________________________________________________________________

          PRODUCT NAME:  VAX Packetnet System Interface     SSA 25.40.15-A 
                         (P.S.I.), Version 4.3

          HARDWARE REQUIREMENTS

          Processors Supported:

          VAX:      VAX 4000 Model 300,

          VAX:      VAX 6000 Model 200 Series,
                    VAX 6000 Model 300 Series,
                    VAX 6000 Model 400 Series

                    VAX 8200, VAX 8250, VAX 8300, VAX 8350,
                    VAX 8500, VAX 8530, VAX 8550, VAX 8600,
                    VAX 8650, VAX 8700, VAX 8800, VAX 8810,
                    VAX 8820, VAX 8830, VAX 8840, VAX 8842,
                    VAX 8974, VAX 8978

                    VAX-11/730, VAX-11/750, VAX-11/780, VAX-11/785

          MicroVAX: MicroVAX II, MicroVAX 2000,
                    MicroVAX 3100, MicroVAX 3300,
                    MicroVAX 3400, MicroVAX 3500,
                    MicroVAX 3600, MicroVAX 3800,
                    MicroVAX 3900

          VAXstation: VAXstation II, VAXstation 3200,
                      VAXstation 3500, VAXstation 3520,



                                       DIGITAL                   July 1990

                                                               AE-LP46C-TE

 


          VAX Packetnet System Interface                    SSA 25.40.15-A
          (P.S.I.), Version 4.3 




                    VAXstation 3540

          VAXserver: VAXserver 3100, VAXserver 3300,
                     VAXserver 3400, VAXserver 3500,
                     VAXserver 3600, VAXserver 3602,
                     VAXserver 3800, VAXserver 3900

                     VAXserver 6000-210, VAXserver 6000-310,
                     VAXserver 6000-410, VAXserver 6000-420

          Processors Not Supported:

          MicroVAX: MicroVAX I


          VAXstation: VAXstation I, VAXstation 2000, VAXstation 3100 Series,
                      VAXstation 8000

          VAX:      VAX- 11/725, VAX-11/782

          Processor Restrictions

          o  At least 1.5M bytes of physical memory

          o  Non-paged dynamic pool computed as follows:

             At least:

             -  60K bytes for the VAX P.S.I. software and data storage,
                plus

             -  13K bytes if the VAX P.S.I. X.29 capabilities are re-
                quired, plus

             -  1K byte for each local DTE, plus



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             -  1.5K bytes for each virtual circuit, calculated as:

                <WINDOWSIZE>*<packetsize + 96>*2 + 700 bytes

                charged to the quota of the using process.

          o  Paged dynamic pool - VAX P.S.I. requires 50 bytes for each
             entry defined in the system DTE logical name table.

          Communications Devices

          One of the following communications devices is required for use
          with VAX P.S.I.:

          o  The KMS1P-A, KMS1P-B and KMS11-B (UNIBUS) products are DMA
             devices. The KMS communications controller executes character
             transmission, reception, and X.25 data link level protocol
             processing in microcode (LAPB only, for packets not larger
             than 1024 bytes). The VAX CPU then processes the X.25 packet
             level protocol. Optional link-level software products and
             tools available for the KMS devices are not required. The
             KMS1P-A and KMS1P-B were previously known as the KMS11-PX and
             KMS11-PY.
















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             In the case of the KMS11-B eight-line device, all lines in
             use must be connected to the same network and must be in the
             same mode (DTE or DCE).

          o  The DUP11 (UNIBUS) and DPV11-DA or DPV11-S (Q-bus) are char-
             acter interrupt devices for LAPB or LAPBE datalink handling
             where CPU cycles are required for X.25 packet and data link
             level protocol processing, and for each character sent and
             received.

          o  The DMF32 (UNIBUS) and DMB32 (BI-BUS) are multi-function
             devices which include a single DMA line. The communications
             controllers perform character transmission, reception, and
             HDLC framing in microcode. The VAX CPU then processes the
             X.25 data link (LAPB or LAPBE) and packet level protocols.

             In the case of the DMF32, only rev. J and later are supported
             with the VAX P.S.I. software, and rev. M is required for
             simultaneous operation of the printer port with VAX P.S.I..
             For the DMB32, rev.J is required.

          o  The DST32 (Busless) is a single line synchronous communica-
             tions device for the MicroVAX 2000. The DST32 supports DMA
             transfers for bit oriented protocols. The communications
             controller performs character transmission, reception, and
             HDLC framing in the microcode. The MicroVAX 2000 CPU then
             processes the X.25 data link (LAPB or LAPBE) and packet level
             protocols.

          o  The DSH32 (Busless) is a multi-function device for the Mi-
             croVAX 2000 and MicroVAX 3100 which includes a single DMA
             line. The communications controller performs character trans-
             mission, reception, and HDLC framing in microcode. The Mi-
             croVAX CPU then processes the X.25 data link (LAPB or LAPBE)
             and packet level protocols.



                                          4

 

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          (P.S.I.), Version 4.3 


          o  The KMV1A-A or KMV1A-SF (Q-bus) communications controller
             executes transmission, reception, and X.25 link level pro-
             tocol processing in microcode (LAPB only, for packets not
             larger than 1024 bytes). The VAX CPU then processes the X.25
             packet level protocol. Optional link-level software prod-
             ucts, drivers and tools, available for the KMV1A device, are
             not required. The KMV1A device was previously known as the
             KMV11-A.

          o  The DSV11 (Q-bus) is a dual line synchronous communications
             device for Q-bus systems. The DSV11 supports DMA transfers
             for bit and character oriented protocols. The communica-
             tions controller performs character transmission, reception,
             and HDLC framing in the microcode. Then, the VAX CPU pro-
             cesses the X.25 data link (LAPB or LAPBE) and packet level
             protocols.

          o  The DIV32 (Q-bus) is a single board, Basic Rate Access com-
             munications device for Q-bus MicroVAX systems running VAX
             ISDN software. The DIV32 supports one ISDN Basic Rate Access
             connection, providing two 64K bps bearer (B) channels for
             data transfer and one 16K bps (D) channel for signaling. The
             VAX ISDN software can establish a connection through the D
             channel, allowing VAX P.S.I. to establish an X.25 connection
             and transfer data via a B channel. Refer to VAX ISDN Software
             Product Description (SPD 31.23.xx) for more information about
             VAX ISDN software and the DIV32.

          o  The DSB32 (BI-bus) is a dual line synchronous communications
             device for VAXBI systems. The DSB32 supports DMA transfers
             for bit and character oriented protocols. The communications
             controller performs character transmission, reception, and
             HDLC framing in the microcode. The VAX CPU then processes the
             X.25 data link (LAPB or LAPBE) and packet level protocols.

          Refer to Table 2 for details of processor and device combina-
          tions and configuration guidelines for VAX P.S.I.

          Block Space Requirements

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          Block Space Requirements (Block Cluster Size = 1):

          Disk space required for       6,000 Blocks
          installation:                 (3.1M bytes)

          Disk space required for       8,000 Blocks
          use (permanent):              (4.1M bytes)

          These counts refer to the disk space required on the system
          disk. The sizes are approximations; actual sizes may vary de-
          pending on the user's system environment, configuration, and
          software options selected.

          For VAX P.S.I. operating in multi-host mode, the system must,
          in addition, meet the requirements for DECnet-VAX; consult
          the DECnet-VAX Software Product Description (SPD 25.03.xx)
          for a complete description of that product's minimum hardware
          requirements.

          OPTIONAL HARDWARE

          Additional communications device(s) subject to the limitations
          described in Table 2 of this System Support Addendum are re-
          quired.

          CLUSTER ENVIRONMENT

          This layered product is fully supported when installed on any
          valid and licensed VAXcluster * configuration. The HARDWARE RE-
          QUIREMENTS sections of this product's Software Product Descrip-
          tion and System Support Addendum detail any special hardware
          required by this product.

          * V5.x VAXcluster configurations are fully described in VAX-
          cluster Software Product Description (29.78.xx) and include CI,
          Ethernet and Mixed Interconnect configurations.



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          On common disks, in order to configure some product specific
          attributes that must remain unique to each system, certain
          components of the product are stored in the system specific
          environment (SYS$SPECIFIC: [SYSxxx]) of the VAX computer on
          which the installation is being performed. The remaining compo-
          nents of the product, including some or all of the executable
          images, will be installed common to all accessing VAX systems.

          Though some or all of the product's executable images will
          exist in the common system directory (SYS$COMMON:[SYSEXE])
          and be executable by all VAX computers sharing this directory,
          it is essential that the product be installed separately on
          all VAXcluster or Local Area VAXcluster licensed VAX systems
          requiring access in order to uniquely configure the product for
          each.

          The same version of VAX P.S.I. must be used on all systems in
          VAXcluster systems accessing a common disk and in Local Area
          VAXcluster configurations.

          SOFTWARE REQUIREMENTS

          VMS Operating System V5.1, V5.2 or V5.3.

          For VAX P.S.I. Multi-host mode, or for any use of DECnet (DLM)
          circuits over a PSDN(s), DECnet-VAX V5.1, V5.2 or V5.3 (either
          end-node or full-function) is required (refer to SPD 25.03.xx).

          For use with the synchronous communications interfaces, the
          appropriate device driver in the VAX Wide Area Network Device
          Drivers V1.1 software is required (refer to SPD 29.64.xx).

          For use with the DIV32 Basic Rate Access communications device,
          VAX ISDN V1.0 software is required (refer to SPD 31.23.xx).

          VMS Tailoring

          For VMS V5.x, the following VMS classes are required for full
          functionality of this layered product:

          o  VMS Required Saveset

                                          7

 


          VAX Packetnet System Interface                    SSA 25.40.15-A
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          o  Network Support

          o  Utilities

          o  Programming Support

          o  Bliss Require Files

          o  User Environment Test Package

          For more information on VMS classes and tailoring, refer to the
          VMS Operating System Software Product Description (SPD 25.01.xx)

          OPTIONAL SOFTWARE

          For VAX P.S.I. Multi-host mode:

          DECnet-VAX V5.1, V5.2 or V5.3 either full-function or end-node.

          If you have more than one VAX P.S.I. Multi-host node, users
          in one Multi-host node can gain access to PSDN(s) connected to
          another Multi-host node if both VAX P.S.I. and VAX P.S.I. Access
          are installed on the same node.

          Certain versions of these products depend upon a specific ver-
          sion of the operating system. Please refer to the System Support
          Addendum (SSA) of the product in question to determine which
          version is required.

          GROWTH CONSIDERATIONS

          The minimum hardware/software requirements for any future ver-
          sion of this product may be different from the requirements of
          the current version.

          DISTRIBUTION MEDIA

          Tape: 9-track 1600 BPI Magtape (PE), TK50 Streaming Tape

          This product is also available as part of the VMS Consolidated
          Software Distribution on CDROM.

          ORDERING INFORMATION

                                          8

 
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          (P.S.I.), Version 4.3 




          Software Licenses: QL-071A*-**
          Software Media: QA-071A*-**
          Software Documentation: QA-071AA-GZ
          Software Product Services: QT-071A*-**


          *  Denotes variant fields. For additional information on avail-
             able licenses, services and media, refer to the appropriate
             price book.

          Supported Public Networks

          Table 1 describes public PSDNs which are supported with VAX
          P.S.I. only in the countries shown. Connections to public net-
          works outside this list are customer supported only. In addition
          to these public PSDNs, certain private PSDNs have been tested
          by Digital and appropriate profiles included in the VAX P.S.I.
          product.

          Since the publication of this SPD, other configurations may have
          been tested. Please consult your local Digital office for any
          questions concerning other public PSDNs.

          ________________________________________________________________

                                    Table 1:
                         Supported Public Networks

                                       Public Network          Comments
                                       and CCITT revi-         and Re-
          Country                      sion(s)                 strictions

          Argentina                    Arpac

          Australia                    Austpac

          Austria                      Datex-P

          Belgium                      DCS

                                          9

 
          VAX Packetnet System Interface                    SSA 25.40.15-A
          (P.S.I.), Version 4.3 


                                 Table 1: (Cont.)
                         Supported Public Networks

                                       Public Network          Comments
                                       and CCITT revi-         and Re-
          Country                      sion(s)                 strictions


          Brazil                       Renpac

          Canada                       Datapac (1976 or
                                       1980)

                                       Infoswitch

          Denmark                      Datapak

          Ireland                      Eirpac (1980)

          Finland                      Datapak

          France                       Transpac

          Hong Kong                    Datapak

                                       Intelpak

          Indonesia                    SKDP

          Italy                        Itapac

          Japan                        DDX (1976, 1980)        See Note 1

                                       Venus-P (1980)

                                       Tymnet




                                         10

 


                                 Table 1: (Cont.)
                         Supported Public Networks

                                       Public Network          Comments
                                       and CCITT revi-         and Re-
          Country                      sion(s)                 strictions

          Luxembourg                   LUXPAC

          Malaysia                     Maypac

          Mexico                       Telepac

          Netherlands                  Datanet 1

          New Zealand                  Pacnet

          Norway                       Datapak

          Portugal                     Telepac

          Singapore                    Telepac

          South Korea                  Dacomnet

          Spain                        Iberpac

          Sweden                       Datapak

          Switzerland                  Telepac (1978, 1980)

          Taiwan                       Pacnet

          United Kingdom               PSS

          United States                Accunet



                                         11

 
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          (P.S.I.), Version 4.3 


                                 Table 1: (Cont.)
                         Supported Public Networks

                                       Public Network          Comments
                                       and CCITT revi-         and Re-
          Country                      sion(s)                 strictions


                                       Autonet

                                       Bell Atlantic

                                       Compuserve

                                       ConnNet

                                       IMPACS

          United States (cont.)        Infonet

                                       Mark*Net Extended
                                       Service

                                       Telenet

                                       Tymnet

                                       Western Union PTN-1

                                       Worldnet

          West Germany                 Datex-P

          Note:

          1. Digital offices in Japan can supply the mandatory additional
             information that explains the special use of VAX P.S.I. with
             the DDX PSDN.


                                         12

 


          VAX Packetnet System Interface                    SSA 25.40.15-A
          (P.S.I.), Version 4.3 



             Unless otherwise acknowledged within the product documen-
             tation, the trademarks under which the services are offered
             are proprietary to the respective national PTT, the owning or
             operating companies, or equivalent organization.

          Configuration Guidelines

          Tables 2 and Table 3 describe the physical hardware configura-
          tions supported by VAX P.S.I. in terms of CPU type and communi-
          cation interface. It is assumed that there are 128 bytes of user
          data per packet in a VAX P.S.I. Native mode configuration where
          data is being sent and received at maximum speeds in both direc-
          tions. These tables indicate configuration numbers for certain
          VAX processors supported at the time of publication.

          The numbers given in the tables are load costs. Load costs in-
          dicate the overhead of full-duplex packet transfer at the indi-
          cated speed. The load units are calculated for an application
          that does no work with transmitted/received data, and indicate
          a maximum packet rate for that configuration. An idle device
          incurs negligible load. Systems should be configured to sustain
          peak load rates.

















                                         13

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          (P.S.I.), Version 4.3 



          ________________________________________________________________

                                     Table 2:
                     CPUs, Maximum Load and Supported Devices

                                                                    Supported
                                            Maximum load            Device(s)
          CPU                               (in_load_units)

          MicroVAX 2000                     100                     DSH32,
                                                                    DST32

          MicroVAX 3100                     350                     DSH32

          MicroVAX II                       160                     DSV11,
                                                                    DPV11-
                                                                    DA,
                                                                    KMV1A-
                                                                    A,
                                                                    DIV32

          MicroVAX 3300/3400                210                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    DIV32

          MicroVAX 3500/3600/3602           330                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    KMV1A-
                                                                    SF,
                                                                    DIV32








                                         14

 
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          (P.S.I.), Version 4.3 

                                  Table 2: (Cont.)
                     CPUs, Maximum Load and Supported Devices

                                                                    Supported
                                            Maximum load            Device(s)
          CPU                               (in_load_units)

          MicroVAX 3800/3900                390                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    DIV32


          VAXstation II                     150                     DSV11,
                                                                    KMV1A-
                                                                    A,
                                                                    DIV32

          VAXstation 3200                   300                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    KMV1A-
                                                                    SF,
                                                                    DIV32

          VAXstation 3500                   300                     DSV11,
                                                                    DPV11-
                                                                    DA,
                                                                    KMV1A-
                                                                    A,
                                                                    DIV32








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          (P.S.I.), Version 4.3 


          ________________________________________________________________

                                  Table 2: (Cont.)
                     CPUs, Maximum Load and Supported Devices

                                                                    Supported
                                            Maximum load            Device(s)
          CPU                               (in_load_units)


          VAXstation 3520/3540              300                     DSV11,
                                                                    DPV11-
                                                                    DA,
                                                                    DIV32


          VAXserver 3100                    290                     DSH32

          VAXserver 3300/3400               210                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    DIV32

          VAXserver 3500/3600/3602          280                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    KMV1A-
                                                                    SF,
                                                                    DIV32

          VAXserver 3800/3900               330                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    DIV32

          VAXserver 6000-210                210                     DSB32,
                                                                    DMB32





                                         16

 
          VAX Packetnet System Interface                    SSA 25.40.15-A
          (P.S.I.), Version 4.3 

                                  Table 2: (Cont.)
                     CPUs, Maximum Load and Supported Devices

                                                                    Supported
                                            Maximum load            Device(s)
          CPU                               (in_load_units)


          VAXserver 6000-310                250                     DSB32,
                                                                    DMB32

          VAXserver 6000 Model 400          300                     DSB32,
          Series                                                    DMB32


          VAX-11/730                        40                      DUP11,
                                                                    DMF32,
                                                                    KMS1P-
                                                                    A/B,
                                                                    KMS11-
                                                                    B

          VAX-11/750                        70                      DUP11,
                                                                    DMF32,
                                                                    KMS1P-
                                                                    A/B,
                                                                    KMS11-
                                                                    B

          VAX-11/780                        120                     DUP11,
                                                                    DMF32,
                                                                    KMS1P-
                                                                    A/B,
                                                                    KMS11-
                                                                    B





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          ________________________________________________________________

                                  Table 2: (Cont.)
                     CPUs, Maximum Load and Supported Devices

                                                                    Supported
                                            Maximum load            Device(s)
          CPU                               (in_load_units)


          VAX-11/785                        180                     DUP11,
                                                                    DMF32,
                                                                    KMS1P-
                                                                    A/B,
                                                                    KMS11-
                                                                    B

          VAX 8600                          400                     DUP11,
                                                                    DMF32,
                                                                    KMS1P-
                                                                    A/B,
                                                                    KMS11-
                                                                    B

          VAX 8650                          500                     DUP11,
                                                                    DMF32,
                                                                    KMS1P-
                                                                    A/B,
                                                                    KMS11-
                                                                    B


          VAX 4000 Model 300                580                     DSV11,
                                                                    DPV11-
                                                                    S,
                                                                    DIV32






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          VAX Packetnet System Interface                    SSA 25.40.15-A
          (P.S.I.), Version 4.3 

                                  Table 2: (Cont.)
                     CPUs, Maximum Load and Supported Devices

                                                                    Supported
                                            Maximum load            Device(s)
          CPU                               (in_load_units)


          VAX 6000 Model 200 Series         250                     DSB32,
                                                                    DMB32

          VAX 6000 Model 300 Series         350                     DSB32,
                                                                    DMB32

          VAX 6000 Model 400 Series         450                     DSB32,
                                                                    DMB32


          VAX 8200/8300                     100                     DSB32,
                                                                    DMB32

          VAX 8250/8350                     125                     DSB32,
                                                                    DMB32

          VAX 8500                          360                     DSB32,
                                                                    DMB32

          VAX 8530                          450                     DSB32,
                                                                    DMB32

          VAX 8550                          550                     DSB32,
                                                                    DMB32

          VAX 8700                          700                     DSB32,
                                                                    DMB32





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          ________________________________________________________________

                                  Table 2: (Cont.)
                     CPUs, Maximum Load and Supported Devices

                                                                    Supported
                                            Maximum load            Device(s)
          CPU                               (in_load_units)


          VAX 8800/8810/882/ 8830/8840      700                     DSB32,
                                                                    DMB32

          VAX 8842                          700                     DSB32,
                                                                    DMB32

          VAX 8978                          700                     DSB32,
                                                                    DMB32

          ________________________________________________________________

                                                        Table 3:
                                         Load Units per Line at Various Speeds

          Device Type        Number     Maximum              Load Units used at speed (K bps)
                             of
                             Lines     Speed      4.8        9.6        19.2       48         64

          DMB32              1          64.0       9          18         36         90         120

          DSB32              2          64.0       9          18         36         90         120

                             or 1       192.0

          DMF32              1          19.2       9          18         36         N/S        N/S

          DPV11-DA or        1          9.6        23         64         N/S        N/S        N/S
          -S*

          DST32              1          19.6       10         20         40         N/S        N/S


                                         20

 
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          (P.S.I.), Version 4.3 


                                                  Table 3: (Cont.)
                                       Load Units per Line at Various Speeds

          Device Type        Number     Maximum              Load Units used at speed (K bps)
                             of
                             Lines     Speed      4.8        9.6        19.2       48         64

          DSH32              1          19.2       10         20         40         N/S        N/S

          DUP11*             1          9.6        23         46         N/S        N/S        N/S

          DSV11              2          64.0       9          18         36         90         120

                             or 1       256.0

          DIV32**            2          64.0       N/S        N/S        N/S        N/S        120



          KMS1P-A            1          19.2       9          18         36         N/S        N/S

          KMS1P-B            1          64.0       9          18         36         90         120

          KMS11-BD/BE***     8          19.2       10         20         40         N/S        N/S

          KMV1A-A or -SF     1          19.2       9          18         36         N/S        N/S


          *    For more than one character interrupt device, multiply the
               load units by 50% to allow for interaction between devices.

          **   The DIV32 supports 2 B-channels at 64K bps per ISDN line.






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          ***  The KMS11-BD/BE are eight (8) line devices; the load units
               indicated above are the load units for each active line at
               the indicated line speed.

          N/S  The use of the device at this speed is not supported by VAX
               P.S.I.
































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          How to Use Table 3

          The maximum system configuration, with a mix of device types,
          is computed by adding the load costs (in load units) for each
          device up to the limit for a given processor type.

          Example 1:

          A VAX 8500 is being used to process VAX P.S.I. Native mode com-
          munications. If the system uses a DMB32 at 64K bps and another
          DMB32 at 19.2K bps, the load units total 156. Assuming these
          devices are fully active, they will consume 156/360 = 43% of
          CPU for communications processing. It is inadvisable to add
          more devices to this CPU, unless it is dedicated to the task of
          communications processing.

          Example 2:

          When one line of a DSV11 is fully utilized on a MicroVAX 3800 at
          64K bps, it consumes 120/390 = 31% of the processor in process-
          ing VAX P.S.I. communications.

          Factors to Consider

          Other factors to consider when configuring hardware devices for
          use with VAX P.S.I. on a given processor are:

          o  Multi-host mode increases the CPU load of packets to or
             from VAX P.S.I. Access systems due to the additional cost
             of DECnet communications to the chosen VAX P.S.I. Access
             node.

          o  Hardware configuration limits, such as power supply, back-
             plane space, bus throughput and mapping registers available,
             and any other restrictions on the number of devices per CPU
             or per bus, must be observed.

          o  Actual/average Packet size in bytes - generally, doubling the
             actual packet size will halve the load units consumed for DMA
             devices, but increase the load units for character-interrupt
             devices by approximately 30 percent.

                                         23

 



          o  The above table assumes that data is sent and received in
             each direction of a full-duplex line in equal ratio. If the
             number of X.25 packets per second is predominantly one-way,
             the load units per line can be reduced proportionately up to
             a factor of 50%.

          [TM] Bell is a trademark of Bell Telephone Companies.

          [R]  The DIGITAL Logo is a registered trademark of Digital
               Equipment Corporation.

          [TM] DECnet-VAX, VAX, MicroVAX, VAXstation and VAXserver are
               trademarks of Digital Equipment Corporation.


























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