Which XML-based web services protocol is used to exchange messages?

Which XML-based web services protocol is used to exchange messages?

• A. REST
• B. JMS
• C. SOAP
• D. XMPP

Answer: (C)

XML-based web services protocol designed for exchanging structured messages between applications is SOAP. SOAP defines an XML envelope with a header for metadata and a body for the actual payload, so different systems can communicate in a consistent, interoperable way. It is transport-agnostic but most commonly used over HTTP, and it supports standardized encoding rules and extensibility through WS-* standards, making it well-suited for formal message exchanges in web services. REST isn’t a protocol per se and isn’t tied to XML by necessity; it’s an architectural style that often uses HTTP and can return XML or JSON. JMS is a Java messaging service API for general messaging inside distributed applications, not a web services protocol. XMPP is an XML-based protocol for real-time messaging and presence, but it’s geared toward instant messaging rather than the structured web services message exchange SOAP provides.

XML-based web services protocol designed for exchanging structured messages between applications is SOAP. SOAP defines an XML envelope with a header for metadata and a body for the actual payload, so different systems can communicate in a consistent, interoperable way. It is transport-agnostic but most commonly used over HTTP, and it supports standardized encoding rules and extensibility through WS-* standards, making it well-suited for formal message exchanges in web services.

REST isn’t a protocol per se and isn’t tied to XML by necessity; it’s an architectural style that often uses HTTP and can return XML or JSON. JMS is a Java messaging service API for general messaging inside distributed applications, not a web services protocol. XMPP is an XML-based protocol for real-time messaging and presence, but it’s geared toward instant messaging rather than the structured web services message exchange SOAP provides.