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RFC316 - ARPA Network Data Management Working Group

发布: 2007-6-23 14:09 | 作者:   | 来源:   | 查看: 13次 | 进入软件测试论坛讨论

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  Network Working Group D. B. McKay
Request for Comments: 316 A. P. Mulleray
NIC: 9346 IBM
February 23 & 24, 1972

ARPA Network Data Management Working Group

The meeting had two different phases. The first included
presentations of applications of networks and development work in the
design to allow data sharing in a computer network, the second was a
working meeting in which was discussed what the data management
working group should do.

Phase I

JOHN SENIOR, Univ. of Penn. and National Board of Medical Examiners,
Phila., PA., described the use of a network to provide access to
models that simulate medical behavior of patients. These models are
used primarily for teaching and testing physicians. The network
provides an interface by which varieties of terminals can connect to
and access these models. Other data bases exist to which access
through a network may be desirable; however, these data bases have a
"polyglot" of organizations making it presently impossible to use
foreign data bases.

HECTOR MAYNEZ, National Library of Medicine, described the MEDLINE
system. This has 1000 journals on-line to which access can be made
via a network. This network, as the one above, provides the
interface for access by various terminals. In this network are four
or five computers with other applications such as CAI, clinical
diagnosis, etc.

RAY BEVERIDGE, MITRE, presented the requirements for the WWMCCS
(World Wide Military Command and Control System) Network. This
network will contain 25 nodes and have a data exchange rate of the
order of 10,000,000 characters per day. Three type of data were
formulated - query data with response on the order of seconds, daily
exchange for updates and reports, and other data for weekly, monthly
or as required reports.

ERICA PEREZ, MITRE, discussed data management for the WWMCCS Network.
The two problems are determining the location of desired data, and
providing the proper security and reliability for vital data. The
location of data bases will be indicated in directories which may
automatically determine which segment is applicable to a query. The
directory will contain lists of data bases, files users and programs.

The directory can be centralized (all at one location), distributed
(split into pieces but where each piece resides at one location)
partially replicated (split into pieces but in which certain parts
may be replicated at different locations) and completely replicated
(the complete directory at all locations).

The data management system will have to deal with possibly different
hardware systems and even different local data managements systems.
One solution is to have a standard data management and data
description language for transmission of requests and data in the
network.

The system will have to provide capabilities for file transfer,
queries, remote batch, and for user communication via a mail box.
The security of the data is maintained by checking user id, terminal
authorization, process authorization and data authorization.

BOB BROWN, General Motors Research Lab., described the network of
computers at the General Motors Research Center. This network at
present consists of an IBM 360/67, a 360/65, a 370/165, three 1800's
and a Sigma 5. All of these are primarily for graphics use except
the 67 and the 165. An example of how data passes through the
network was given. The styling department develops a design on an
1800. Data on this design is sent to the 67 for stress and shape
analysis and the results returned to the 1800. After a design is
developed, it is sent to the 65-1800 combination for detailed
analysis for production. Many of the computers are running GM's own
operating systems, and the network control consists of macros added
to these operating systems. Interfacing is done by providing
specific conversion modules to the called when the specific
conversion is required. The 67 will eventually be replaced by a
hierarchical multiprocessor based on the CDC Star-100.

PHIL MESSING, MITRE, is setting up an experiment to test the
practicability of interfacing a network standard data management
language with local data management systems. In this experiment, a
user will make a request in the network language, this request will
be transmitted to a node, and translated to the language of this
local node. At present, three local systems have been selected to be
used - MADAM at MIT, LISTAR and Lincoln Labs., and NASIS at
NASA/Ames.

It is not expected that the common data language will be able to
handle all possible requests that may be made. The language should
be able to handle the most common requests, otherwise, some means of
interaction may be set up in order to allow the transmission of more
information to the target system than the common language may allow,
or finally, a user can utilize the local target language.

At a later stage in the experiment, a user will input a query, the
local host will determine where the query is to be sent, the
transmission takes place, it is accepted by the target node,
translated to the target node's local language and processed.

ERNIE FORMAN, MITRE, is developing a special, simple data management
system specifically for the purpose of measuring and testing
organizational techniques for control, directories, and files. The
question to be answered is whether each of these three functions
should be centralized, or distributed, how, and where. The initial
experimental arrangement is to have the control and directory
centralized at the Rand node, and the files to be distributed at
UCSB, Rand, and BBN. The files are each split vertically and
distributed, this organization chosen to present the more difficult
case.

DICK WATSON, SRI, described some extensions of NIC (Network
Information Center) that he would like to see, and that would involve
network data management facilities. The first would be the ability
to process text from one text processor by another. Second, it would
eventually be desirable to distribute the NIC journals. A first
stage of this would be to have several NLS (Network Library System)
systems around the network, each with its own journal. The problems
with this first stage would be in coordination of numbering and in
organization of the directory. A second stage would be one in which
the journal might reside, in part, on other than NLS systems.

A third extension is to enable the NLS System to use the results of
some other cataloging or citation and bibliographic referencing
systems as input to the NLS catalogs. The fourth extension would be
to enable other data management systems to generate data of more
general type and be usable by the NLS.

PHASE II

The second phase of the meeting was a working meeting to try and
organize the committee and try and set up an active working interest
group.

The following names presently form the committee. These are the
people who have shown active interest, and are engaged in related
activities:

Douglas B. McKay IBM Research (Chairman)
Abhay Bhushan MIT
Ernie Forman MITRE
Dorothy Hopkin University of Illinois
Phil Messing MITRE
A.P. Mullery IBM Research
Erika Perez MITRE
A. Shoshani SDC
S. Taylor MITRE
Bob Thomas BBN
Frank Ulmer NBS
Dick Watson SRI
Dick Winter CCA

It would be very useful in follow-on meetings to have representative
from the Form Machine group. Discussions on various uses of the Form
Machine by a Network Data Management facility are bound to come up in
later meetings.

A member of the form machine group would be an asset to the Data
Management Committee.

Discussion on network data management covered many aspects of the
problem with a general discussion on just what people want to be able
to do with a network data facility.

The following list, gleamed from the discussion, represents the
possible stages of development:

1. Transmission Facility - the Network Data Control Facility (DCF)
is able to route requests for files to the proper node. The
location and name must be specified.

2. Location Catalog- The DCF now has available to it a catalog which
contains the locations of the data sets to be used in the
network. Requests for files may be made by name only, the
location being determined by the DCF.

3. Description Catalog - Descriptions, as well as data sets can be
transmitted in the network. It is assumed these descriptions
exist as files at local nodes. A target node can make use of the
description to properly convert the data set to its own format.

4. Data Conversion Modules - Data descriptions are received by this
module of the DCF. Based on the descriptions, conversion
programs are called or generated which will transform a file to
the form required by the target node.

5. File Access Command Interface - this module is able to convert a
request for a file from a network data language to the local
language at which the file is located.

6. Data Access - This module, an extension of the network data
language and the interface modules, allows access to pieces of
data as specified in the data language, and generates the proper
local access commands.

7. Data Management Interface - This is the final stage, at which
general types of commands can be interfaced to local data
managements systems, providing general interaction among
different data amanagement systems at different nodes.

It was generally agreed that the ability to access all data and
different data bases is a goal which is worth achieving. There was
discussion in what is the best way to achieve this goal, and the
actual implementation techniques that could be used to achieve this.
It was agreed that the data base interfacing problem should be
studied in more detail and several people more willing to write
reports on a representative problem when they have more results from
their work.

There was also a discussion concerning the data language and whether
it is suitable or not. One fact should be made clear, the results of
this committee should not fail or succeed on the outcome of the data
language question. The initial proposal recommends the Datalanguage
as de facto standard that will be adopted in the network because of
its support and availability. The group should be able to recommend
changes when changes are shown to be necessary.

The Datalanguage discussion did point out the need for having data
set descriptions cataloged and referable by name - D. Winter, said
that he would look into this problem.

The proposal (RFC304) for a network data facility should be read
again and discussed in more detail at our next meeting. The proposal
says we can implement and achieve a stage 3 capability with what we
know today. It would be a useful stepping stone to a stage 5 and
stage 6 capability.

Related to the stages of development described above the following
studies are now in progress and will help us answer pertinent
questions.

A. Bhushan is studying a stage 1 type of network operation with
extension in local catalogs to contain entries of network data sets
of interest locally, to enable automatic calls to foreign data sets.

E. Perez will be studying the network catalog structure in more
detail and will publish an RFCon her work.

Many questions were raised about the use of the data language as a
network standard. There are two people that have volunteered writing
up their investigations of this important study.

Frank Ulmer will be looking at various data management systems to see
if their data structures are describable in terms of the
Datalanguage. In addition, the NIC represents one important network
data base that could be distributed through the network. Dick Watson
will try to describe the NLS Journal structure in terms of the
Datalanguage.

If there are any other people in the ARPA network or outside within
hearing distance of this memo who may know about any real or
potential applications of data sharing in a network, please submit an
RFCin a letter to someone associated with the Data Management
committee describing it.

Appendix -- Meeting Attendees

William Benedict USAFETAC Bldg. 159 Navy Yard Annex Wash. D.C.

Roy Beveridge MITRE

Abhay Bhushan MIT, Project Mac, Cambridge, Mass.

Bob Brown General Motors Research Lab.

Elizabeth Fong National Bureau of Standards, Wash. D.C.

Ernie Forman MITRE

Glen Grazier USAFETAC Bldg. 159 Navy Yard Annex Wash. D.C.

Dorothy Hopkin U. of Ill., Adv. Comp. Bldg., Urbana, Ill.

Hector S. Maynez National Library of Medicine

Doug B. McKay IBM Research Center

Phil Messing MITRE

Al Mullery IBM Research Center

Erika Perez MITRE

John Senior Univ. of Penn. and National Board of Medical
Examiners, Phila. PA.

Arie Shoshani SDC, 2500 Colorado Ave., Santa Monica, Cal.

Martin Snyderman Smithsonian Science Info. Exch., Wash. D.C.

Eric Swarthe National Bureau of Standards, Wash. D.C.

Suzanne Taylor MITRE

Bob Thomas BBN

Frank Ulmer National Bureau of Standards, Wash. D.C.

Dick Watson SRI

Richard Winter Computer Corporation of America

[This RFCwas put into machine readable form for entry]

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