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                          ANF10 - The Protocol

                              Tom Wimberg

                        University of Louisville

                      Louisville, Kentucky  40206

Presentation by Eric J.  Werme, Digital Equipment Corporation.   Writeup
by  Scott  G.   Robinson, University of Arizona Computer Center, Tucson,
Arizona 85721.


ANF-10 is a communication  protocol  that  allows  for  complex  network
topologies   and  support  of  unit  record,  terminal,  and  task  data
transfers.  ANF-10,  implemented  to  meet  needs  of  the  DECsystem-10
environment,  was  available  before  the  DECNET  protocols  of similar
functionality.  Although the bases for ANF and DECNET were the same, the
protocols vary widely in message format and sequencing.

          S*                      N*,S*                    S*
     +--------+                 +--------+              +--------+
     | DC72NP |                 |  DN81  |              | DC72NP |
     |  DN92  |                 |  DN82  |              |  DN92  |
     +--------+                 +--------+              +--------+
               \               /          \            /
                \             /            \          /
                 \    N*     /              \   N*   /
                 +----------+               +--------+
                 |  DN87S   |               |  DN87  |
                 |  DN85    |---------------| DC75NP |
                 +----------+               +--------+
                      |                          |
                      |                          |
                    N*|S*                      N*|S*
                 +----------+               +--------+
                 | DEC-10   |               | DEC-10 |
                 | System   |               | System |
                 +----------+               +--------+

                     Example Network Configuration

                   Legend: N* = Non-Sequential Nodes
                           S* = Sequential Nodes

ANF-10 has two kinds of node processing:  sequential and non-sequential,
the  difference  being  whether  a  node  can  process numbered messages
received out of sequence.  Non-sequential nodes hold  messages  received
out  of  sequence  for  sequential  nodes  that  are  neighbors to them.
Messages whose destination is the non-sequential node itself will be put
in   sequence   before   processing   on  those  messages  begins.   The
non-sequential nodes will issue messages to their neighboring sequential

nodes   whenever   the   next   message   in   sequence   is  available.
Non-sequential  message  processing  allows   for   complex   topologies
consisting of alternate routing paths among nodes.

Data transfer in ANF is supported  for  terminals,  card  readers,  line
printers, and processes (task-to-task).  Virtual terminal facilities are
available among hosts that support  an  MCR  (monitor  command  routine)
device.   A  user from any network terminal can SET HOST to another node
that has an MCR.  Protocol fields for other devices are defined but  not
necessarily supported by Digital.

                        Protocol Characteristics

The ANF protocol consists of two parts:  the  Network  Command  Language
(NCL),  similar  in  function  to NSP in DECNET;  and the Device Control
Protocol (DCP), similar in function to DAP in DECNET.

NCL messages consist  of  three  types:   Unnumbered  Control,  Numbered
Control, and Numbered Data.  The formats are similar, as show below:

        Unnumbered Control    ----> NCT (DNA SNA) NCA NCN OPD
        Numbered Control      ----> NCT DNA SNA NCA NCN 0 CM
        Numbered Data         ----> NCT DNA SNA NCN DLA DCP

The  NCT  field  is  the  Network  Control  message  Type  and  contains
information  used  to determine the kind of node processing and the type
of message.  The DNA and SNA fields are the Destination Node Address  (a
number)  and the Source Node Address (a number).  These fields determine
where a message is routed within the network.   The  NCA  field  is  the
Network  Control  Ack  number.   This  field  is the last message number
received by the SNA from the DNA.  The NCN field is the Network  Control
message  Number.   The  field  is  incremented for each numbered message
transmitted from SNA to DNA.  This field is inserted into the NCA  field
ACKing  a  numbered message.  The OPD field stands for Optional Data and
depends on the NCT message type  subfield.   The  CM  field  is  an  NCL
control  message  that  is  used to establish and control logical links,
network topology, and nodal configuration.  The DCP field  is  dependent
upon  the  destination  device  for  a  logical  link  identified by DLA
(Destination Link Address) and is a Device Control Protocol message.

Field Definitions

The NCT extensible field appears as:

Bits         B7    B6    B5    B4    B3    B2    B1    B0
          | EXN | NSN |  I  |  TR |  RH |  Message type   |

          Where  EXN is the extensible field bit
                 NSN is a 1 for messages from a
                         non-sequential node

                 I   is a 1 to indicate this message
                         is an interuupt message

                 TR  is unused but is dedicated to
                         indictae this is a traced

                 RH  is a 1 if the DNA and SNA fields
                         are included (routing header)

                 Message Type is a number indicating
                         the type of message this is:

                                   0 = Numbered Message
                                   1 = NCL ACK
                                   2 = NCL NAK
                                   3 = NCL REP
                                   4 = NCL START
                                   5 = NCL STACK
                                   6 = Node-ID
                                   7 = Unused
                                   Types 1-6 are Unnumbered Control

The DNA and SNA fields contain the extensible binary node  number.   The
NCA and NCN fields are 3-bit message numbers.

The OPD field for Unnumbered Control messages apply only to Node-ID, NCL
START,  and  NCL  STACK.   For  other messages this field is empty.  The
format of the field is NNM SNM SID.  NNM is the node number  (extensible
binary)  for  the  SNA;   SNM  is the station name and is the extensible
ASCII name for the SNA;  SID is the software identification field.   SID
has  two  parts:  the extensible ASCII name and version of the operating
system, and the extensible ASCII creation date.

Formats of the DM and DCP fields will be presented later.

Unnumbered Control Messages

Processing of unnumbered control messages also differentiates sequential
and  non-sequential  nodes.   Sequential  nodes  can  only  process  and
generate Node-Id messages and always ignore the NCA and NCN fields.

The functions of NCL ACK, NAK, REP,START, and STACK message are  similar
to  DDCMP messages of the same name and will not be discussed here.  The
Node-ID message is used to  initialize  communication  between  neighbor
nodes.   The Node-ID is the first NCL message issued after DDCMP startup
on a communication line and is always sent without a routing header  (no
DNA  and  SNA).   Thus  it  can  only  be exchanged with neighbors.  The
Node-ID  contains  two  important  pieces  of  information   about   the
characteristics of a particular node:  1) the node number (and name) and
2) whether a node  is  sequential  or  non-sequential.   If  a  node  is
sequential  it  must  be connected to the network (terminated) through a
non-sequential node.

NCL Startup

"NCL Startup" applies to what must be done to  bring  a  node  into  the
network  and  begin  numbered  message exchange.  Startup for sequential
nodes simply involves an exchange of  Node-ID  with  its  non-sequential
neighbor.   When  the  exchange  is  complete,  numbered messages can be

Startup for non-sequential  to  neighboring  sequential  nodes  involves
exchanging  Node-IDs.  Startup for a non-sequential neighbor involves an
exchange of Node-IDs followed by  an  NCL  START-STACK-REP-ACK  sequence
similar  to  DDCMP.   The  message  numbering  (NCN  field) applies on a

node-to-node basis as opposed to  the  numbering  on  logical  links  in

Sequential Node Startup
   Node-ID ----------------------------------------> (Received by Non-
                                                      Sequential Node)
          <----------------------------------------  Node-ID
          <----------------------------------------  Numbered messages
Non-Sequential Node Startup
   Node -ID --------------------------------------->
           <---------------------------------------- Node-ID
   NCL START -------------------------------------->
           <---------------------------------------  NCL STACK
           <---------------------------------------  NCL REP
   NCL ACK  --------------------------------------->
           <---------------------------------------  Numbered Messages

Numbered Control Messages

Numbered control messages, the CM field in the NCL, formats  above,  are
differentiated  from  numbered  data  messages  by a zero (0) DLA field.
These messages  are  used  for  network  and  logical  link  management.
Network    management    functions   are   associated   with   topology,
configuration, and station control.  Logical link  management  functions
are  for  logical  link origination, termination, and flow control.  The
format of CM is:

Network Management:

   Neighbors             --> CNT 003 NNM0 LVL0 NNM1 ... LVLn
   Request Config        --> CNT 004
   Configuration         --> CNT 005 OBJ0 NDV0 PID0 OBJ1 ... PIDn
   Station Control       --> CNT 007 STC
Logical Link Management:

   Connect               --> CNT 001 DLA SLA DPN SPN MML FEA
   Disconnect            --> CNT 002 DLA SLA RSN
   Data Request          --> CNT 006 DLA DRQ

The CNT field is  an  extensible  binary  number  giving  the  count  of
remainig  characters in this control message.  Because of the CNT field,
control messages can be stacked in a numbered message.  DLA and SLA  are
the  extensible  binary  logical link addresses, one for the Destination
node and the other for the Source node.  OBJ is the object  type  for  a
device.  NDV is the number of that object type at that node.  STC is the
station control protocol message and will not be discussed here.   Other
fields will be discussed as they are used.

Network Management

After NCL Startup several network management functions must be performed
to  enable  other  nodes in the network to know about the node that just
came on-line.  This is accomplished by the non-sequential nodes  sending
Neighbors   messages   to  all  known  nodes.   These  messages  contain
information regarding the node number (NNM) and network level (LVL)  for
all  nodes it currently knows.  This means that each non-sequential node
must keep information about all nodes  in  the  network.   As  might  be
surmised,  this  takes  a lot of storage in large networks.  This scheme
also has the side effect of having  many  Neighbors  messages  exchanged
whenever  a  node  comes on-line.  An interesting correctness proof that
applies  to  the  ANF  scheme  of  topology   information   appears   in
Communications  of  the  ACM, July 1977, titled A Correctness Proof of a
Topology Information Maintenance Protocol  for  a  Distributed  Computer
Network  by  William  D.  Tajibnapis of the MERIT Computer Network.  The
MERIT scheme is a subset of the ANF scheme in  that  it  only  exchanges
information  about  nodes that have changed status instead of the entire
information base.

The Neighbors message is used  in  non-neighbor  nodes  to  perform  NCL
Startup, much like Node-ID message.  A START-STACK exchange must be done
to obtain information such as node name.  It makes no  difference  to  a
non-neighbor  node  whether a node is sequential.  The non-neighbor node
always communicates with it non-sequentially  because  sequential  nodes
terminate in non-sequential ones, i.e., terminating non-sequential nodes
provide a non-sequential interface  for  their  sequential  nodes.   The
START-STACK  also  establishes  a path by which numbered messages can be
exchanged with the new node.

Another aspect of Network Management consists of each node's features or
devices  characterized  by  object  types  (OBJ).   A  node  wishing  to
determine another node's configuration  sends  a  Request  Configuration
message  to  it.   The  other  node  would  respond with a Configuraiton
message reflecting its device and functional  characteristics  including
the  count  (NDV)  of  each  object  type  available.  The Configuraiton
information can be used to determine whether a device exists at  another
node  without  an  attempt  to  establish a logical link to that device.
Normally, a Configuration message is sent after NCL Startup  from  other
nodes  in  the  network  to  a  node  that  has  just come on-line.  The
Process-ID (PIP) field in a Configuration message is a zero byte.

    Object types:
             0 - MCR   Monitor Commands Routine
             1 - TTY   Async Terminals
             2 - CDR   Card Reader
             3 - LPT   Line Printer
             4 - PTR   Papertape Reader
             5 - PTP   Papertape Punch
             6 - PLT   Plotter
             7 - MTA   Magnetic Tape
            10 - DTA   DECtape
            11 - TSK   Process (Task)
            12 - RDE   Remote Data Entry

Logical Link Management

A logical link is a data path from a  source  object  to  a  destination
object on the network.  Multiple logical links are multiplexed into each
physical link with each logical link having a source link address  (SLA)
and  a  Destination  Link Address (DLA) associated with it.  The SLA and
DLA are established by a Connect procedure.  In general, the source node
initiating the connection issues a Connect Message with no DLA specified
(zero) and the SLA field set to a number that it will associate with the
link.   The  destination  node will either confirm or reject the connect
request.  To confirm  the  connection,  the  destination  node  sends  a
Connect Message with the DLA field set to the received SLA and supplying
a number in the SLA field that it will  associate  with  the  link.   To
reject the connection, a Disconnect Message is sent with a DLA being the
SLA of the Connect message and a zero SLA field.  The RSN byte  contains
the reason for the disconnect.

DPN stands for Destination Process Name and SPN for Source Process Name.
Each  consists  of two parts:  1) Object type and 2) Process-ID (Unit or
Task Identifier).  The Process-ID for  TSK  objects  is  the  extensible
ASCII  Identifier  (similar  to  a  fielname)  and PPN (UIC).  For other
object types this field is the unit number of that object on that  node.
The  DPN  is used in a Connect Initiate to determine which device is the
destination of the logical link.  The DPN and SPN fields in the  Connect
Message  provide  enough  information  about  the source and destination
objects so that some validity checking can be performed.

The ANF flow control scheme allows the destination of data on a  logical
link  to determine the rate at which data messages (DCP) are transmitted
to it.  This is accomplished by the Data Request message.  The DRQ field
specifies  the  number  of  free  buffers  available  for  a destination
transfer.  This number is  added  to  any  data  request  count  already
associated  with  the  DLA.  This mechanism can be overridden by sending
the DCP message as an Interrupt message (NCT subfield I set to 1).   All
input from TTY objects is sent as interrupt messages.  There are no data
requests from the host to the TTY object.

Logical link termination is accomplished by a disconnect procedure.  The
node  terminating  the logical link issues a Disconnect with the DLA and
SLA filled with the numbers for this link and the  RSN  byte  set  to  0
(Normal Disconnection).  The destination node responds with a Disconnect
Confirm which is a Disconnect  message  with  the  SLA  being  0.   Upon
receipt of the Disconnect Confirm the logical link is terminated.  Other
RSN codes are:  1) object type not available;  2) too many connects;  3)
too  many  connects to process;  4) proccess (OBJ, Task Identifier) does
not exist;  10) reassign this link to  another  node,  NNM  follows  RSN
byte.  An RSN of 10 is how SET HOST is effected.  The current host sends
a Disconnect message on a TTY object's DLA with RSN of  10  and  a  node
number  from  the SET HOST.  The node issues a Disconnect Confirm to the
original host and attempts a Connect Initiate  to  the  new  host's  MCR
object.   If  this  is successful the terminal is now on the other host.
If it is unsuccessful DN92 and DN8x software attempts a reconnect to the
previous host.  If all this fails the user gets TTY NOT CONNECTED.

Termination of logical links can occur when a  node  goes  off-line  and
there  are  logical  links  to  it.   This  condition  is  determined by
receiving a Neighbors message without  that  node  listed  in  it.   The
Neighbors message processor removes all logical links to that node.

Example of Logical Link Creation

  Connect Confirm

  CI(0,7)  ------------------------->
          <--------------------------  CC(7,1)
          <--------------------------  DRQ(7,2)

  Connect Reject

  CI(0,7)  ------------------------->
          <--------------------------  CR(7,0) or DC(7,0)

Logical Link Termination

  DI(1,7)  ------------------------->
          <--------------------------  DC(7,0)

  CI(DLA,SLA)   - Connect Initiate
  CC(DLA,SLA)   - Connect Confirm
  CR(DLA,SLA)   - Connect Reject
  DC(DLA,SLA)   - Disconnect Confirm
  DI(DLA,SLA)   - Disconnect Initiate
  DRQ(DLA,SLA)  - Data Request

                         Numbered Data Messages

Numbered data messages are distinguished from numbered control  messages
by  the specification of the DLA (not 0) with which they are associated.
The numbered data messages contain the Device Control  Protocol  message
that is used in data transfer and device characteristic control.

Device Control Protocol

The Device Control Protocol is the DCP field in numbered data  messages.
Its format is:

  Supported Messages:

            Data          -- CNT <001> (DATA)
            Data W/ EOR   -- CNT <002> (DATA)
            Status        -- CNT <003>  STC STD
            Control       -- CNT <004>  DCT CDT
  Unused Messages:

            User ID       -- CNT <005>  PPN PSWD UNAME ACCT GROUP
            File Spec     -- CNT <006>  FST FEA FDES

Data is transferred on a logical link with the  Data  and  Data  W/  EOR
messages.   Both  forms of data messages are processed identically.  The
CNT field is the number of characters excluding the CNT  field  in  this
DCP  message.   The  CNT  field allows for stacking DCP message for each

The Status message contains two fields, STC and STD.  STC is called  the
Status  Code  and STD is called the Status Data.  The STC specifies what
is to be done with the STD.  STC can be 0  for  STD  being  the  current
device  status;   1 for STD containing bits to get in the device status;
2 for STD containing bits to clear in the device status;   3  for  fatal
error  (transfer  abort).   STD bit definitions are device dependent and
will be discussed as each device is presented.

The Control message contains two device dependent fields, DCT  and  CDT.
DCT  is  called  Device  Control  and  CDT  is called Control Data.  The
Control message is used primarily on TTY objects.

                          Device Dependencies

CDR Objects

Card reader objects use a compressed data  format  and  allow  for  very
little  device  control.   The data consists of bytes with the following

       Bytes                           Meaning
      lccccccc            Seven-bit coded character

      0ldddddd            Blank compression

      00leeeee            Repetition of next byte

      0000ffff            Unencoded format


         ccccccc is the following code:
                 Number          Punches in Rows 1-0
                   0             None
                   1             1
                   2             2
                   3             3
                   4             4
                   5             5
                   6             6
                   7             7
                  10             8
                  11             9
                  12             8-2
                  13             8-3
                  14             8-4
                  15             8-5
                  16             8-6
                  17             8-7

                 Number          Zone Punches
                   100           12
                    40           11
                    20           0

      dddddd is count of blanks

      eeeee is count of repetitions (0-31)

      ffffgggggggg is twelve-bit unencoded character

The Status bits (STD) are:

 Byte 0  |EXN| P | J | F | E | R | H |MER|

 Byte 1  |   |   |   |STP|OFL| 0 |HEF|EOF|

         EXN = Extensible bit
           P = Pick fail
           J = Jam
           F = Stacker full
           E = Bad Punch
           R = Registration error
           H = Hopper empty
         MER = Master error bit

         STP = Reader has stopped
         OFL = Off-line
           O = Overrun
         HEF = Hardware EOF
         EOF = End-of-file card detected

There are no DCT and CDT fields defined for the CDR object.

LPT Objects

Line Printers use a compressed data format similar to  the  CDR  object.
Very  limited  control over the line printer can be performed.  The data
format is:

                Data                   Meaning

                lccccccc       Non-repeated ASCII character
                0ldddddd       Number of repeated blanks
                00leeeee       Number of repetitions for next character

The Status bits (STD) are:


 Byte 1  +-------------------------------+
         |   |   |   |   |PQU|NIN|PSF|PLO|

                  EXN - Extensible field bit
                  HMR - Hammer jam
                  SLW - Paper slew
                  OFL - Off-line
                  PAJ - Paper jam
                  OUT - Paper out
                  MER - Set on any error
                  FTL - Fatal error (?)

                  PQU - Bad print quality
                  NIN - No ink
                  PSF - Paper stacker full
                  PLO - Paper low

There are no DCT and CDT fields defined for the LPT object.

TTY Objects

TTY data is sent as 8-bit ASCII characters.  There is  extensive  device
control available.

The status bits (STD) are:


 Byte 1 +-------------------------------+

 Byte 2 +-------------------------------+
        |   |   |   |   |   |   |   |DSR|

                EXN - Extensible field bit
                TAP - TTY TAPE mode
                PAG - TTY PAGE MODE
                IMO - Image output
                IMI - Image input
                XOF - X-OFF typed
                ULC - Lower-to-uppercase conversion
                DEC - Deferred echo

                CAR - If DTR not set means ring, else carrier
                DTR - Data terminal ready
                NCR - No CRLF
                LIM - Line input mode
                TIW - TTY input wait
                 FF - Hardware form fead
                 HT - Hardware tabs

                DSR - Data Set Ready

The DCT and CDT fields are:

        DCT             CDT
        0               EPL     Echo Pipeline Marker
        1                       Character Gobbler
        2               CHR     TTY Characteristics
        3               D1G     Dial-out

        EPL is the Echo Pipeline Marker number  MOD(256)

        CHR is the extensible binary characteristics:
                (one field for each of the following)
                # of milliseconds after backspace <010>
                # of millilseconds after horizontal tab <011>
                # of milliseconds after line feed <012>
                # of milliseconds after vertical <013>
                # of milliseconds after form feed <014>
                # of milliseconds after carriage return <015>
                Receive speed
                Transmit speed
                Width of TTY carraige
                Auto CRLF position
                Element number
                2741 bits

         DIG is the extensible ASCII string of digits to dial.

                             DCP Operation

CDR Objects

The card reader object returns card images as long  as  there  are  data
requests  outstanding and the STP status bit is not set.  The STP status
bit becomes set on an error such as reader off-line or when an EOF  card
(12-11-0-1-6-7-8-9)  is  read.  The STP bit must be cleared by an STC of
"clear bits" and the STD set to the STP bit.  If it is not  cleared  the
card  reader  object  will not send any data regardless of data requests
outstanding.  When an error occurs a status message (STC=0,  STD=status)
is  sent  with  MER  (master  error) and STP set.  When an EOF is read a
status message is sent with MER cleared and STP set.  The  EOF  card  is
transmitted before this status.

LPT Ojbects

Data is transmitted to LPT Objects as data requests  become  outstanding
from  it.   The only error indication is if the LPT goes off-line.  This
is indicated by the MER status bit.

TTY Objects

After the logical link is established an exchange of characteristics  is
performed.   The  node having the TTY object sends a TTY characteristics
message followed by a  status  message.   Then  the  host  will  send  a
characteristics message followed by a status message.  The TTY object is
now ready for data transfer.

Input character processing involves sending the character  to  the  host
and  processing  protocol  break  characters.   To do this there are two
operating modes:  local echo and deferred echo.  Local  echo  refers  to
the  TTY  object  node  echoing  input  characters  instead of the host.
Deferred echo is the  mode  under  which  the  host  echoes  characters.
Whenever  a  control  character (other than TAB) is typed the TTY object
send a status message indicating that the object  is  in  deferred  echo
mode,  the  data  character  that  caused  the  mode change, and an Echo
Pipeline Marker.  EPL is incremented for each character  sent  from  the
TTY  object  to  the host.  In deferred echo, all characters are sent to
the host with no echoing performed, and all have an Echo Pipeline Marker
appended  to  them.   When  the  host  wants to return to local echo, it
issues a Echo Pipeline Marker with the last EPL field it  has  received.
If  the  EPL  sent matches the one at the TTY object then the TTY object
goes into local echo and  a  status  message  is  sent  reflecting  this
change.   In general, a status message is always sent to the host on any
change in status regardless of reason.  The host can force a  line  into
deferred  echo by sending a status message setting the deferred echo bit
(DEC).  The host can remove deferred echo by clearing that bit.

Output  character  processing  involves  formatting   those   characters
according  to  the  status  and  TTY  characteristics.   This  makes the
terminal appear to have SCNSER handling  of  width  and  no  CRLF.   The
Character  Gobbler  message  causes all output to the TTY object at that
node to be thrown away.  This is used to handle ^O.

Session Attendees

Ed Jordan - Goodyear Atomic             Richard Hilmer - E.I. DuPont
Richard Ruszkay - DuPont                Heidi Wmburn - Sambos
Frank Ivan - Compuserve                 Paul Malquist - Brigham Young Univ
Howard Wactlar - Carnegie Mellon        Richard Kann - On-line Systems
P Usdanandan - TIER Bombay              Colin Strutt - British Airways
A.R. Lis - SDRL                         Chuck Knopf - E MU
Jim McBride - York Ryerson              R. Imossi - Brookhaven National Labs
George Lucas - Pfizer                   Daniel Grim - Univ. of Deleware
Jim Pope - Gallaudet College            Buster Hale - Univ. of Miss.
H. Prindle - DEC                        Becky Wilson - Univ. of Ark.
Howard Merritt - INTEL                  Marty Palmieri - DEC - IPS
Wayne Wall - C.S.M.                     James Smith - First Church
Deny Crugnola - DEC                     Ben Timmerman - Univ. of Tenn.
Frank Kyle - Vanderbilt Univ.           Tom Lobb - Interprovincial Pipe Line
Julia King - Ledule Lab                 McCann - Rapida Inc.
Marty Shuttleworth - Livermore Labs     Edward Mulrean - Catholic University
Harold Stout - UT Health Sci Ctr        Marilee Thompson - Princeton Plasma
Brent Sterner - U of W. Ontario         Lori McHardy - UWO
J. G. McHardy - UWO                     C E Burgart - SAI
Casey Henderson - Fed Judicial Ctr      Edward Aiken - Naval Research Lab
Ed Smolsky - Western Michigan Univ.     Paul Bennett - Harvard Business Schl
Gary Koenig - Coordinated Mgmt Sys      Barbara Rudolph - Western Electric
C.J. Welsch - Western Electric          Robert McQueen - Stevens Institute
Dick Schofield - Univ. of New Hamp.     Rich Feghu - DEC
Roy Rezac - TELEMED                     Jim Thomas - Univ. of New Orleans
Duane Winkler - Union Carbide           Dou Hanley - Syracuse Univ.
Robert Duncan - Sycor                   Barry Howard - MFE Computer Ctr
James Wilson - Hughes Aircraft          Gene Autrey - Hunley - SRI
Bob Reardon - Schlumberger              Don Dossa - DEC
T.M. Loomis - Tx. Board of Ctl.         R R Rodriguez - Southwest Tx. State
Peter Chiu - U of Miss                  Rich Melberg - Raytheon Co.
Kirk Topits - CH2M Hi11                 Nicholas Alter - U. of New Hamp.;
Roger Uphoff - DEC St. Louis            Larry Jasper - Monsanto
John Schaefer - Monsanto                Dennis Jogensa - DEC St. Louis
Donald Brandt - EG+G                    Eric Werme - DEC
Scott Robinson - U. of Az.