MapSnack presentation at slideshare.com : view here
Virtualization is an emerging technology on x86 platform simplifying deployment and configuration of complex information technologies. In free and open source software for geoinformatics area, however, this trend is not yet fully reflected or leveraged. Contribution introduces results and experiences with FOSS geospatial virtual appliance called ‘MapSnack’. MapSnack is a fully pre-installed and pre-configured geospatial virtual appliance that runs on any standard x86 machine in a self-contained, isolated environment.
A vision of MapSnack is to accompany raw geospatial data which comes in different formats with functionality to explore, query, share and manage content. That is merge data with functionality logic to simplify their absorption by consumer. MapSnack eliminates the installation, configuration and maintenance effort associated with deploying complex stacks of software for web mapping.
There are basically two approaches how to achieve that. First is traditional and nowadays very popular LiveCD appliance, second is a virtual appliance
1. Geospatial LiveCD Appliance:
This approach takes Knoppix LiveCD concept for fast deployment on user’s machine. LiveCD on one hand simplifies deployment and readiness to use geospatial appliance but on other hand remastering and maintenance of such system is difficult since intrinsic system is read only. LiveCD advantage is however in that it can run on any virtual or real machine which supports x86 ISA (Instruction Set Architecture) thus decision to let geospatial appliance run on real or virtualized (partitioned) hardware is left up to user. Another advantage of LiveCD system is embedded compressed file system which is automatically extracted during the boot up.
2. Geospatial Virtual Appliance – Mapsnack
Recently much attention of IT have been drawn towards virtualization on x86 platform. Although there are many different levels of virtualization (hardware, operating system, application) virtualization in this contribution is treated as ability to run multiple operating system on one CPU or one single computer. Important differentiation from the term emulation is that virtualization partition real hardware into multiple running context while emulation does it all in (higher) software layer. Virtualization is used in different areas such as server consolidation, running legacy applications within legacy OS’es, running untrusted applications in secure isolated sandboxes, application mobility, clean/single service design and many others. MapSnack as geospatial virtual appliance is minimum sized Linux virtual machine with web user interfaces for deploying instant geospatial infrastructure and applications. Thus provides to the consumer advantage of quick deployment with nearly zero-based installation and minimum skills to get it running.
MapSnack consist of latest UMN MapServer and P.Mapper with sample dataset. Underlying operating system is Debian Sarge 3.1r2 with latest updates. VMware Player has been chosen as virtualization platform to run MapSnack. Since it is not optimal to stick to one virtualization platform, future version will be virtualization platform independable, thus running a microinstall in the first run of appliance. Virtualized environment has an advantage that anybody can extend or modify it. User gets all necessary preinstalled and preconfigured software without even need to change his current production environment. This opens doors for Windows users who would like to combine comfort of Windows based GUI with performance and effectivity of single service virtual appliance based on Linux..
This approach of geospatial virtual appliance answers also areas of MapSnack usability :
1. Portable map browsing – nowadays map browsers rely on internet connections. In case connection or server is broken and maps are urgently needed MapSnack can be quickly deployed as off-line /backup (or stand alone) map server.
2. Encapsulating geospatial data with functionality – geospatial data providers might want to add value to customers by providing not only processed data coming from various electromagnetic sensors but also by providing software appliance for viewing and manipulating geospatial content.
3. Education of OGC standards (WxS) on stable and ‘always available’ source of geospatial content.
MapSnack can be downloaded from :http://mapsnack.mendelu.cz
I am very suprised that no one ever used term “Geospatial Virtual Appliance” on interent – at least Google returned only 2 references… So from now on I will start to monitor number of Google responses on this term…try it too.. btw. MapSnack (Geospatial Virtual Appliance) got ‘HONORABLE MENTION’ sign by VMWare in ‘Ultimate Virtual Appliance Challange’ competition. check here
I’ve tested AJAX based approach for displaying maps on web page. I took sample area north to Brno 20x 20 km covered by various geodata including VHR IR images. I had to intercept HTML requests to map server to see what it takes to generate map of particular range and layer. (I had no access to map server, nor I took care what mapping engine serves maps, but it was not in format of WMS). I found quite simple prototype of AJAX display on mike page and I bend it little bit to work with geographicaly referenced maps (actually I needed JTSK system used here in Czech Republic). Conclusion is that AJAX approach for map display has lot of potential since is is elegant, extensible and transparent for end user (just save your page and you may run locally your client or include your client on your own page. Also more about AJAX vs. Flas approach for map displaying see David Blasby’s blog On my sample you may zoom in/out and pan. In zoom level 4 you will get IR aerial images. tested on IE6 and NN6.
I am excited to announce born of MapSnack. I and my colleague Jachym have created experimental Live Linux CD with GIS capability called ‘MapSnack’..your fast food for GIS. Interesting fact is that it can be run directly on HW or as virtual machine from VMware. The reason to do it was to give data consumers not only processed data but also basic functionality to view, analyse and publish them. Moreover installation time is either zero (in case of live runing) or just copy ISO file to your computer to run it from VMware. But may be it is crazy … you go for a shoping and buy an ice cream and you get fridge for free…:))
download iso [669 MB] – you can burn ISO on CD and run as Live Linux
download VMX config [1 KB] to run ISO file as virtual machine
If you don’t have VMware Workstation, go to VMware player to download free virtual machine player either for Windows or for Linux so you can enjoy running LiveCD on top of your host OS.
Details to run MapSnack in VMware Player: Download both files (ISO + VMX) into the same folder – named for example MapSnack. When you double click on VMX file you will get VMware player running and asking you to create new identifier…just confirm. Then MapSnack enters full screen mode…to get out back to your host OS pres Ctrl+alt.