TileCache is one of several open source GIS tile server solutions.  Others include MapProxy and GeoWebCache.

TileCache is a python based solution and obtains imagery from a WMS service and persists that imagery to the file system via DiskCache.

Installing TileCache on Windows/IIS

1. Download TileCache from one of the links on TileCache.org.
2. Launch IIS Manager and create a site, application or virtual directory pointing to the "tilecache" folder.
3. Open the newly created endpoint (e.g. http://localhost:83/TileCache/) in a browser and notice that you have a map with broken tiles.
4. Change the extension of tilecache.cgi to tilecache.py
5. Edit tilecache.py by removing the first line and accessing the config file directly (see http://viswaug.files.wordpress.com/2008/02/croppercapture19.png)

from TileCache import Service, cgiHandler, cfgfiles

if __name__ == '__main__':

    svc = Service.load("D:\\code\\tilecache\\tilecache.cfg")

    cgiHandler(svc)

• Modify index.html to reference tilecache.py (instead of tilecache.cgi). 
• Launch Turn Windows features on or off and check "Internet Information Services/World Wide Web Services/Application Development Features/CGI"
• Back in IIS Manager  register *.py (Add Script Mapping with Request path=*.py, Executable="c:\python27\python.exe" %s %s, Name=Python27)
• Attempt to access a tile (e.g. http://localhost:83/TileCache/tilecache.py?LAYERS=basic&FORMAT=image%2Fpng&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&STYLES=&SRS=EPSG%3A4326&BBOX=-180,-90,-90,0&WIDTH=256&HEIGHT=256) 
• If it worked you're done!  Otherwise read on.  (I received An error occurred: No section: 'cache' because I used the SVN trunk). 
• Return to tilecache.py and add brackets around the path  Service.load(["D:\\code\\tilecache\\tilecache.cfg"]).
• And now my map works...my tiles are being saved to \tmp\tilecache (e.g. D:\tmp\tilecache\basic\01\000\000\003\000\000\001.png)

Configuration TileCache

Open tilecache.cfg  and search for the [cache] section.  Modify the base value as necessary:

[cache]

type=Disk

base=g:\tilecache\Cache

Create your services simply by introducing a new section:

[Assets]

type=WMS

layers=2,3,4,5,6,7,8,9,10,11,12,13,14,15

url=http://usgvwhansendev1:5000/arcgis/services/DevVegasN/MapServer/WMSServer?TRANSPARENT=TRUE

extension=png

extent_type=loose

srs=EPSG:4326

spherical_mercator=true

levels=22

These tiles are accessible using a WMS query string (e.g. http://localhost:83/TileCache/tilecache.py?LAYERS=basic&FORMAT=image%2Fpng&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&STYLES=&SRS=EPSG%3A4326&BBOX=-180,-90,-90,0&WIDTH=256&HEIGHT=256) and assume 4326 projection.  

The metacarta sample test service is accessible in other projection as discovered by http://vmap0.tiles.osgeo.org/wms/vmap0?REQUEST=GetCapabilities&SERVICE=WMS.  They include 4269 and 900913.

Generating tile using a the 3857 projection requires modifying index.html and the tilecache.cfg.

[Test3857]

type=WMS

layers=river

url=http://labs.metacarta.com/wms/vmap0

extension=png

extent_type=loose

spherical_mercator=true

bbox=-20037508.34,-20037508.34,20037508.34,20037508.34

srs=EPSG:900913

levels=20

And the change to the open layers code in index.html to overlay the OpenStreetMap with the river layer:

function init(){

    var map, layer, options;

    options = {

      projection: new OpenLayers.Projection("EPSG:900913"),

      displayProjection: new OpenLayers.Projection("EPSG:4326")

    };

    map = new OpenLayers.Map('map', options);

    var mapnik = new OpenLayers.Layer.OSM("OpenStreetMap (Mapnik)");

    map.addLayers([mapnik]);

    var layer = new OpenLayers.Layer.WMS( "Rivers", "http://localhost:83/tilecache/tilecache.py?", {layers: 'Test3857', format: 'image/png', TRANSPARENT: true } );

    map.addLayers([layer]);

}

External Links

http://tilecache.org/docs/README.html

http://viswaug.wordpress.com/2008/02/03/setting-up-tilecache-on-iis/

http://www.esdmdata.co.uk/tilecache-on-iis7-how-to