System.Net/WCF Diagnostics SDP package helps us with the ability to enable and collect logs for fault analysis and monitoring of WCF Service and ASP.Net application hosted on Azure/On-Premise.
 - WCF tracing can be enabled for WCF Service or WCF Client (Example - Windows forms/ASP.Net).
 - System.Net tracing is meant only for client applications, basically traces outgoing http web requests.

Below is relevant MSDN documentation for configuring System.Net and WCF tracing.

Configure System.Net tracing
http://msdn.microsoft.com/en-us/library/ty48b824(v=vs.110).aspx

Configure WCF tracing
http://msdn.microsoft.com/en-us/library/ms730342(v=vs.110).aspx

System.Net trace output is a text file, you can just open it and look for possible issues. WCF trace output requires a special tool called Service Trace Viewer, please follow the below link for more information.
http://msdn.microsoft.com/en-us/library/ms732023(v=vs.110).aspx

Here are the download and KB links for the SDP package.
https://dsazure.blob.core.windows.net/azuretools/SYSTEM_NET_WCF_TRACING_global.DiagCab
https://support.microsoft.com/kb/2952803

Once you capture the traces, you can either analyze yourselves or open a case with Microsoft Azure Support for further assistance.