The Log Service in EPiserver CMS storing information how many page accesses that is done for a certain page (in the standard templates delivered by EPiserver). The statistics are based on log4net.
Flow
1) The User access a page that includes a image (to PixelImg.aspx) located in the masterpage
2) The PixelImg.aspx creates a log message to the logger EPiServer.UI.Util.PixelImg
3) In the default configuration an UDP message is send to the Log Service by a log4net appender.
4) The Log Service receives the message and distributes it to all its Log Analyzers.
Reading from LogService
In the default distribution from EPiserver the log Analyzers can be queried by a web service over TCP (TCP is used so it not is necessary to have a web service as a back-end server for this functionality).
Configure the Log Service for remote server