Web service performance depends on workload defined with the message input, web server's hardware and network resources, and involved algorithms. For a given algorithm and hardware infrastructure, it degrades by increasing message sizes or number of messages. A message overhead also occurs when signature and encryption headers are attached to SOAP messages. It requires realization of complex cryptographic operations for each message and additional parsing of the XML messages with increased size. This paper is the evaluation of the web service performance, analyzing the platform and security impact of implementation of the most common WS-security standards, i.e. XML signature and XML encryption.