ArcInfo 8 in Detail

Where does one begin when there is so much that is new, so much that can be confusing? Let us begin with the names and terminology.

ARC/INFO. Though often misspelled in the past as Arcinfo, Arc/Info, and such, the official, trademarked name up until version 7 was in fact ARC/INFO. Starting with version 8, however, the official name has been changed to ArcInfo. I think that from a philosophical point of view this says a lot. First, it is an indication that although it is founded on the previous versions of the software, the new version is significantly different, with more to come. Second, it gives me the sense that ESRI is falling in line with the rest of the software industry, where EveryOneAndTheirBrother has an UpAndDown name these days. And this may be a stretch, but the disappearance of the forward slash from the name also is an indication for me of the waning importance of UNIX, where the forward slash is king, from the future of ArcInfo.

Now that I have raised the thorny UNIX issue, I will quickly back off and get back to it later.

Let's tackle the ArcInfo versus ArcGIS terminology. One of the greatest sources for anxiety that I have heard is whether the command line, AML, ArcTools, and the rest of the traditional functionality of ArcInfo is going away. The answer is an emphatic “No.” All of ARC/INFO 7.2.1 is still available in ArcInfo 8.Here is an analogy between the old and new components of ArcInfo: think of the difference between a computer running in DOS, without any Windows interface – that would be ARC/INFO 7. Now think of a Windows NT machine, where a DOS window is available, in case you want to use the old DOS commands or fire up an old DOS software package – that would be ArcInfo 8. Does that make sense?

Also included in ArcInfo 8, is a new software called “ArcGIS,” which is comprised of ArcMap, ArcCatalog, and ArcToolbox. “Old” ArcInfo is still there, but you're going to have a whole lot more power and flexibility if you use ArcGIS. Both are available, but they are not the same, nor are they built on top of each other. ArcGIS is a brand spanking new, object-oriented, software, written with all new COM components called ArcObjects.

If the new part is called ArcGIS, what do we now call the “old” part? ESRI calls the two components Desktop ArcInfo (the “new” stuff, or ArcGIS) and Workstation ArcInfo (the “old” stuff). One of the most obvious differences between the two is that Workstation ArcInfo runs in both UNIX and NT, but Desktop ArcInfo only runs in Windows NT. Which gets us back to UNIX, doesn't it? Wait, we'll get back to that.

Does ArcGIS, or Desktop ArcInfo, have all the functionality of Workstation, or “old” ArcInfo? No, not yet. The main components that have been migrated are Arcedit and Arcplot, and portions of Arc, Network, Tables, and INFO. TIN and Grid have not been migrated, and many of the functions of Arc are only indirectly available. ArcGIS consists of three components: ArcMap, which is the combined editing, query, and mapping component that has absorbed much of Arcedit, Arcplot, and Network; ArcCatalog which has absorbed components of Arc, Tables, and INFO; and ArcToolbox, which has absorbed the remainder of Arc. Of these components, ArcMap and ArcCatalog are based on the new ArcObjects. ArcToolbox is merely a new (and improved) forms-based interface to “old” ArcInfo commands - a sort of crossover component that bridges the gap between the two versions.

The functions served by ArcMap and ArcCatalog are executed and run in Windows NT alone. However, and this is where we finally get back to UNIX, ArcToolbox functions are executed either in NT or UNIX. “How's that?” you ask. Workstation ArcInfo has been modified so that it can be executed locally or remotely, immediately or in batch. Since ArcToolbox executes “old” ArcInfo commands, it too can take advantage of this capability. I shall elaborate.

Imagine that you are cleaning a small coverage on your NT workstation. No problem. You run it locally and right away. However, suppose you have to intersect several dozen coverages, you can instruct a remote UNIX ArcInfo application server to execute the command, either right away or at a specified time. This relegates the UNIX workstation (or the NT application server, for that matter) to handling big disk I/O, CPU, and RAM jobs, and the desktop computer to handling smaller tasks and launching jobs.

Play close attention! What we are witnessing here is a rapid evolution of the software towards the Web. In the near future, especially after ArcIMS is released, we are likely to see application servers serving up GIS “brains” over the Web, with the user interface being a somewhat-intelligent application running inside a Web browser. In other words, instead of all the brains residing locally in an ArcInfo desktop machine, we will see Java applications that are somewhat GIS savvy interacting dynamically in real time, with a heavy duty server around the corner or across the world. A far cry from today’s “real” GIS and funky IMS applications, where you click on the browser and eventually receive a picture of the answer.

Whoa! How did I go from explaining the modules of ArcInfo 8 to discussing science fiction GIS? Hah! Not science fiction at all. ArcInfo 8 (8.0.1 to be precise) is in my opinion the beginning of a rapid and wild ride towards truly distributed GIS for ESRI, even for the common installation in the small county or city down the road. So saddle up, hang on tightly, and get ready for a fun ride.