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OCR for page 25
4
Technical Path to an Open System
The advantages of a digital production environment for data-intensive prod-
ucts such as nautical charts and chart information were discussed in the previous
chapters. The questions that remain concern the details of how to achieve the
transformation most efficiently and rapidly.
This chapter reviews NOAA's digital production activities and outlines the
steps necessary to move the digital system forward in the short and long term in
the most cost-effective and technologically advanced way. Detailed descriptions
of NOAA's current nautical information systems are found in the technical re-
view and evaluation of ANCS II (Goodchild et al., 1995~.
CURRENT SOFTWARE TOOLS
ANCS II is a digital chart production system developed for NOAA through a
private vendor. ANCS II comprises six major custom software modules in addi-
tion to commercial software (approximate number of lines of custom code for
each module is shown in parentheses):
task management (40k lines)
source logging (20k lines)
source evaluation (20k lines)
nautical information database software (160k lines)
chart graphics database software (240k lines)
chart finishing (20k lines)
Task management, source logging, and source evaluation are functions for
which ANCS II provides integrated software tools. Outside ANCS II, NOAA has
25
OCR for page 26
26
NAUTICAL CHART PROGRAM
a stand-alone database system for source logging. Task management and source
evaluation currently are carried out manually.
The nautical information database (NIDB) software manages the application
of new source data to the NIDB, the repository of scale-independent vector data.
The chart graphics database (CGDB) software manages the maintenance of vec-
tor data describing scale-specific depiction of NIDB data in specific chart prod-
ucts. This information on how to build each specific chart product from the NIDB
is stored in the CGDB. Both NIDB and CGDB are approximately 3 percent loaded
at this time, although the data are not yet up to date. Chart-finishing software
produces a raster chart image from the CGDB vector data.
Mariner, a commercial software product, is used in conjunction with NIDB
and CGDB software to cull survey source data from soundings to be retained in
the NIDB and to select from NIDB soundings that will be shown in a particular
chart product. Mariner has a small installed base (fewer than 100 licenses), and
unlike other products that are part of ANCS II, the vendor has no plans at present
to link Mariner to a routinely supported platform; consequently, it will be expen-
sive to maintain.
The Super Computer-Assisted Revision System/Computer-Assisted Compi-
lation (SCARS/CAC) is a software tool developed from commercial off-the-shelf
(COTS) products and chart-finishing software used in ANCS II to compile and
edit raster chart images. The data repository associated with SCARS/CAC con-
sists of raster images representing each chart product. This repository is fully
loaded, but is not up to date for all charts. SCARS/CAC allows cartographers to
edit raster images of paper chart products, and it eliminates the expense and delay
associated with manual engraving. Current capabilities require scanning markups
and applying changes to the raster chart by superimposing the markup. Planned
refinements will increase the ability of SCARS/CAC to accept vector source data
as well as scanned (raster) images.
Most of the workstation hardware on which ANCS II components were de-
veloped is obsolete by present-day standards. Furthermore, the components of
the ANCS II operating system are no longer routinely supported by the vendor.
This will make future maintenance expensive and complicate the replacement of
obsolete hardware. To move digital production system tools forward in a direc-
tion consistent with the themes and considerations described in chapter 3, NOAA
would need to move to a hardware platform and operating system that could be
updated and expanded with COTS software and hardware (hereafter referred to
as "sustainable operating environment"-for example, Windows NT or UNIX/
open systems). This move would also give NOAA greater flexibility in managing
the total life-cycle costs of operations and maintenance refurbishment, replace-
ment, and system evaluation.
To make the transition to an open environment, decisions must be made on
how best to implement each functional component of the data management and
production system in software.
OCR for page 27
TECHNICAL PATH TO AN OPEN SYSTEM
27
PATH FORWARD
To move forward, choices will have to be made in selecting in-house tools,
contractor-developed tools, and COTS software to create the most economical
means of providing required functions. The evaluation of each component should
take into account the performance and productivity, as well as the total life-cycle
cost, of each alternative. Some limits on performance may be acceptable (e.g.,
with COTS products) if they can be acquired and maintained at a much lower
cost.
In general, these trade-off analyses need to employ a cost-recovery or cost-
benefit analysis that takes into account total life-cycle costs. In the following
sections, the elements that should to be taken into account in conducting the
evaluation of ANCS II are discussed. In each case, comparison should be made
between the migration and maintenance cost of the existing ANCS II or SCARS/
CAC component and the cost of a COTS alternative. This comparative informa-
tion could be used to support a decision to either migrate the ANCS II component
to a sustainable operating environment or abandon the ANCS II component and
use COTS (and SCARS/CAC) software for this function. The following discus-
sion examines alternatives for each function.
Task Management
Automated task management is important for the efficient maintenance of
nautical chart data and products. Migration and maintenance costs of the ANCS
II task management components should be compared to the costs of COTS prod-
ucts that provide similar functions. In conducting the evaluation, it should be
noted that the nature of tasks to be managed in the evolving data management and
production environment will change over time and may differ (even in the near
term) from the ANCS II tasks if ANCS II is not deployed as designed.
Source Logging
Source logging refers to tracking source material disposition from the time it
arrives at NOAA, through its use in updating charts and other information products,
to its storage in an archive. Source logging is necessary to the efficient manage-
ment of source material for use in updating NOAA databases and products.
Source Evaluation
Source evaluation is the analysis of source materials for reliability and rel-
evance to the updating of databases and products. Source evaluation is important
to the efficient and accurate application of new source data to databases and
products.
OCR for page 28
28
NAUTICAL CHART PROGRAM
Vector Database Management
The master vector database (the NIDB in ANCS II) is at the heart of NOAA's
function as data manager. Broadly, this database is the repository of the largest-
scale (most accurate) representation of nautical chart information for U.S. waters.
New source information updates this database, and the database, in turn, updates
data sets and products.
As with the other elements of the ANCS II system, migration and mainte-
nance costs of the NIDB software component could be compared to the cost of a
COTS solution to the vector database requirement and serve as the basis for a
decision to either (1) migrate all or part of the NIDB software to a sustainable
operating environment or (2) abandon the NIDB software and use COTS products
for this function. In conducting this comparison, it should be noted that not all
functions of the NIDB software may be needed, depending on the choice of output
management tools (see below). If the NIDB software is retained, the Mariner com-
ponent might still be replaced with COTS products if the existing Mariner com-
ponent cannot be migrated economically to a sustainable operating environment.
Three main options for loading the vector database (the NIDB in ANCS II)
are (1) loading specified themes for critical regions from existing source data,
(2) importing Digital Nautical Chart/Vector Product Format (DNC/VPF) data,
and (3) digitizing NOAA paper charts. These options are not mutually exclusive.
It appears that loading data from an appropriate combination of the sources
above is a reasonable route to acquiring sufficient vector data for creating prod-
ucts in the short term. If SCARS/CAC continue to be used (see below), vector
data used to update raster images in SCARS/CAC could also be brought back to
the vector database with relatively modest effort and cost. New source data could
routinely be brought into the vector database once it is operational.
On-Line Data Warehouse
To meet evolving customer needs in the long term, it is likely that NOAA
will need to develop the capability of making digital data available to users and
vendors directly through an on-line data warehouse. Such a service would pose
substantial challenges to NOAA technical, financial, and organizational-as
well as create the need for additional expertise to develop appropriate network-
ing, distribution, and interactive capabilities. To enable vendors to provide prod-
ucts from NOAA data with NOAA's official sanction, NOAA might consider
developing standards and procedures to ensure that the data reach users without
degradation.
Output Management
Output management includes the production of raster, paper, and vector prod-
ucts, as well as the generation of data sets to be made available through a central
OCR for page 29
TECHNICAL PATH TO AN OPEN SYSTEM
29
data clearinghouse or warehouse that would be easily accessible to users. The two
main alternatives are:
(1) Vector editing of output. Migrate ANCS II CGDB and chart-finishing
software to a sustainable operating environment and develop software to convert
vector data from the CGDB to a format suitable for export to electronic chart
vendors and users (this requires loading the CGDB).
(2) Raster editing of output. Use SCARS/CAC to produce raster and paper
products and develop software to convert vector data from the master vector data-
base to a format suitable for export to electronic chart vendors and users. This
may require more extensive software development, since the master vector data
is not compiled to specific scales.
Alternative (2) is the (:C)TS alternative, since SCARS/CAC is built largely
on COTS software. Note that with either alternative it will be necessary to de-
velop or acquire software to extract vector data for export to electronic chart
vendors and users. The alternatives must be compared in terms of total life-cycle
costs. It is likely that database loading costs will be greater for the first alterna-
tive, while (new) software costs will be greater with the second alternative.
EXAMPLES OF ALTERNATIVE SYSTEMS
The following are three examples of possible alternatives for the data man-
agement and production system:
1. ANCS II as envisioned in the Nautical Charting Services Production
Modernization Plan
2. partial ANCS II with SCARS/CAC
3. SCARS/CAC plus COTS, no ANCS II
These examples illustrate the range of possible configurations and are illustrated
in figures 4-1, 4-2, and 4-3.
Alternative 1 (figure 4-1~. ANCS II is implemented as envisioned. NOAA
proceeds with full deployment of ANCS II as described in the Nautical Charting
Services Production Modernization Plan (NOS, 1995) and discontinues further
development and use of SCARS/CAC. NIDB and CGDB are fully loaded. A
migration strategy is developed and pursued to move ANCS II to a combined
hardware and software environment that makes it economically sustainable.
Alternative 2 (figure 4-2~. Partial ANCS II with SCARS/CAC. NOAA
retains the NIDB software and database components of ANCS II, as well as task
management, source logging, and source evaluation, and links the retained ANCS
II software with SCARS/CAC. The retained parts of ANCS II are migrated to a
sustainable platform; Mariner is replaced by COTS as appropriate. Source data
are managed and maintained in the NIDB and routed from there to SCARS/CAC.
OCR for page 30
30
Source P
..-..
NIDE
; ~
Vector
: Themes:
. .
. , _
., ~ .
NAUTICAL CHART PROGRAM
I Alternative 1 |
~-
ANCS II ANCS II _
SourceP.' _ Source
Logging ~Ed aluation
Pit' ~
ANCS II
NIDB
Software
I ,
ANCS II
EC
(to be
den eloped)
1
,
ANCS II ANCS II
CGDB ' _ Chart
Sore are , Finish
JO
\
SCARS ~CAC ~\
_ _ _ _ _ _ \
,%~
. .
..
Raster
: Separates:
. .
, .
.,~ .
-
_
Vector
· Data
Products
r Rasterlpaper
~Product
EC = electronic chart
p = paper
v = sector
r= raster
FIGURE 4-1 ANCS II as envisioned. Note: Components not used in this configuration
are indicated win broken lines.
SCARS/CAC remains the production system for raster and paper chart products.
Vector products are provided from the NIDB with software to be developed to the
extent that it is loaded.
Alternative 3 (figure 4-3~. SCARS/CAC plus COTS, no ANCS II. ANCS
II is abandoned entirely. SCARS/CAC is developed further and integrated with a
vector database and COTS software for management, logging, evaluation, and
other functions. Vector products are provided from the vector database, with soft-
ware to be developed, to the extent that it is loaded.
The alternatives described above require different database preparation
methodologies. Alternative 1 (ANCS II as envisioned) requires population of
both the NIDB and the CGDB. In this alternative, the CGDB must be loaded
through the automated and interactive processing of data from a fully populated
OCR for page 31
TECHNICAL PATH TO AN OPEN SYSTEM
31
NIDB using ANCS II. Alternatives 2 and 3 do not make use of the ANCS CGDB
and, therefore, do not require it to be loaded. However, they each require the
development (or procurement via COTS) of new software to compile vector prod-
ucts from the main vector database (NIDB or others).
NOAA has several choices for achieving the population of the NIDB:
· using original hydrographic source data and compiling it into vector data
· using the digitizing capabilities of ANCS II to populate the NIDB from
paper-source photographic separates
· using commercial contractors to digitize paper-source photographic
separates
· using digital data automated by the Defense Mapping Agency in the digi-
tal nautical chart format
ANCS II
Source p.v
/
_'
Vector
Themes
Alternative 2
ANCS II
Source
.
Logging
p.\ ~
p.r
NOB
Source
Evaluation
ANCS II
P,~
NIDB
Soft vare
ANCS II
CGDB
Soft vare
SCARS / CAC
_ ~
~J C ~SePar ~ ~CGDB
' -"'
ANCS II
EC
(to be
den eloped)
. ........
: ANCS II
Chart
Finish
Vector
Data
Products
rRaster/Paper
' Product
EC = electronic chart
p = paper
= sector
r= raster
FIGURE 4-2 Partial ANCS II with SCARS/CAC. Note: Components not used in this
configuration are indicated with broken lines.
OCR for page 32
32
NAUTICAL CHART PROGRAM
| Alternative3 l
, .
: ANCS II :
Source
Logging
-
Management
p.` Logging
Source ~Es aluation
(sit` or manual)
' in\'
.1
I/ ,'
Vector
Themes NIDB
. ......
: ANCS II
ANCS II
EC
(to be
developed)
, ..............
: ANCS II :
NIDB
Software
, ..............
ANCS II
, .............
: ANCS II
. .
CGDB Chart
: Softu are : : Finish
. , .
\ps.r
\9 Of / 1
~SCARS / ~^
,
Vector -> EC
Software /-
~(to be /
/ des eloped) '/r
C ~ ~ -'),
Raster
Separates
C
r Raster/Papcr
Prr`A''rt
Vector
v ~ Data
Products
EC = electronic chart
CGDB v - ~ ector
r= raster
FIGURE 4-3 SCARS/CAC Plus COTS, no ANCS II. Note: Components not used in this
configuration are indicated with broken lines.
These choices are not mutually exclusive. A discussion of costs associated
with the generation of vector data for the NIDB is provided in appendix E.
Under alternative 2 (partial ANCS II with SCARS/CAC), the CGDB
does not exist. Options for the population of the NIDB are the same as for
alternative 1.
Under alternative 3 (SCARS/CAC plus COTS, no ANCS II), the CGDB also
does not exist. The requirement to move toward production of ECDIS (Electronic
Chart Display and Information System) vector data would imply that a vector
database of some type would still exist with content similar to the proposed ANCS
II NIDB. Again, the options for populating it would be the same as alternative 1,
except that the option to use ANCS II digitizing capabilities for population would
not exist.
OCR for page 33
TECHNICAL PATH TO AN OPEN SYSTEM
COMMENTS ON THE NOAA MODERNIZATION PLAN
33
The Nautical Charting Services Production Modernization Plan (NOS,
1995) (see summary in appendix B) recognizes that decisions must be made in
the near future about the best options for fulfilling the functions of the digital
nautical data management and production system. In light of the choices avail-
able to NOAA and discussed in this report, the plan would benefit from being
modified to reflect more explicit decisions and to ensure that the necessary in-
formation to support these decisions is generated in a timely fashion. Such a
modification would minimize the likelihood of using scarce resources on projects
that will not be sustained.
Representative terms from entire chapter:
vector database
