4.1 Probe Message Example
A client performing stock trades needs to locate a Target Service of Type i:StatisticalAnalysis and requires that service in the next 5 seconds. Using an implementation of WS-Discovery, it multicasts the following Probe message, which contains the <MaxResults> and <Duration> elements, as defined in this document. The <MaxResults> and <Duration> elements contain the termination criteria that limit the number of responses to one and the duration to 5 seconds. This following Probe message is sent from a client that is implementing [WS-Discovery1.1].
Example 1: Probe message sent using [WS-Discovery1.1]
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(01) <s:Envelope (02) xmlns:a="http://schemas.xmlsoap.org/ws/2005/08/addressing" (03) xmlns:d="http://docs.oasis-open.org/ws-dd/ns/discovery/2009/01" (04) xmlns:i="http://statistics.example.org/2003/stats" (05) xmlns:s="http://www.w3.org/2003/05/soap-envelope" > (06) <s:Header> (07) <a:Action> (08) http://docs.oasis-open.org/ws-dd/ns/discovery/2009/01/Probe (09) </a:Action> (10) <a:MessageID> (11) urn:uuid:3afd5e21-de48-4277-8119-f25ebdd9890a (12) </a:MessageID> (13) <a:To>urn:docs-oasis-open-org:ws-dd:discovery:2009:01</a:To> (14) </s:Header> (15) <s:Body> (16) <d:Probe> (17) <d:Types>i:StatisticalAnalysis</d:Types> (18) <MaxResults xmlns="http://schemas.microsoft.com/ws/2008/06/discovery">1</MaxResults> (19) <Duration xmlns="http://schemas.microsoft.com/ws/2008/06/discovery">PT5S</Duration> (20) </d:Probe> (21) </s:Body> (22) </s:Envelope> (23)
Lines 18 and 19 show the termination criterion inserted into the Probe message.
A Target Service host is aware of several Target Services that match the Type the client is looking for. However, it is limited to responding with a Probe Match containing information about only one Target Service. If it is able to respond within 5 seconds, it replies back to the client with a Probe Match message containing information about one such service.