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

Configure WCF tracing

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.

Here are the download and KB links for the SDP package.

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