I’ve said before that I work in a hybrid shop– part ESRI, part Open Source. We use GeoExt/OpenLayers/GeoServer/PostGIS for the Enterprise stuff, and ESRI for the analyses, some specialized cartography, and the easy way out on one-off projects. I mostly blog about the Open Source stuff, ’cause that’s where my heart (and budget) lays.
So, now for some ESRI Fan geek-dum. Plus the obligatory work around. Fair warning:
Probably my favorite feature introduced with 9.3 is Layer Packages. Right click on a layer group, choose to export to layer package, and ArcGIS packages up your layer as a compressed layer group that you can send to friends, colleagues, and enemies.
Problem– sometimes the layer groups don’t work when you try to open them at the other end. So I’ve taken to testing them– create, double click to test (and thus decompress) and make sure there are no memory errors part-way through. I discovered a good work-around when there are memory errors– the packages decompress just fine with 7-Zip. What I’ve taken to doing now to ensure my friends, colleagues, and enemies can use my layer packages is to create, unzip with 7-zip, and re-zip with 7-zip as a *.zip file. 7-Zip and WinZip, etc. are much more stable than the engine used by Esri, and I haven’t had errors in the creation of the layer group, just the automatic decompression of it.
In essence, I’m using layer packages to help me organize the data to send, but using good old regular compression software to deliver it.
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If you like layer packages at 9.3, you may be pleased to know that the functionality has been extended to map documents in version 10 with map packages. I would imagine your same work around would apply.
If I may point out the advantage to sharing layers and maps in this way is that in addition to sharing your data, you are also sharing any cartographic properties you have applied to it, i.e. symbology, labeling behavior, drawing extents, etc. We are finding layer packages very helpful for users who are not GIS-savvy but will benefit from viewing well-symbolized data in something like ArcGIS Explorer.
We haven’t made the transition to 10 yet, but nice to know map packages are now an option. That really takes it to the next level.
You’re right about sharing symbolization. I used layer packages to send a colleague about 2GB of data without having to worry about interpretation and symbolization. I was always annoyed that symbolization of layers were so cleverly built into geodatabases where, IMHO, they don’t belong (this is GIS, not CAD!). This allows the portability that such functionality allowed while retaining the abstraction of data and representation.