EchoToken, Timestamp and POS
Request Sample:
<OTA_ReadRQ
xmlns="http://www.opentravel.org/OTA/2003/05" Version="1.0" TimeStamp="2005-08-01T09:30:47+08:00" EchoToken="echo-abc123">
<POS>
<Source>
<RequestorID Type="22" ID="PMS1"/>
</Source>
</POS>
<ReadRequests>
<HotelReadRequest HotelCode="ABC">
<SelectionCriteria SelectionType="Undelivered" ResStatus="Book"/>
</HotelReadRequest>
</ReadRequests>
</OTA_ReadRQ>
Response Sample:
<OTA_ResRetrieveRS
xmlns="http://www.opentravel.org/OTA/2003/05" Version="1.0" TimeStamp="2005-08-01T09:31:00+08:00" EchoToken="echo-abc123">
<Success/>
</OTA_ResRetreiveRS>
POS
All incoming messages except the OTA_NotifReportRQ are expected to contain a POS element with a RequestorID identifying the sending PMS.
EchoToken
All incoming messages are expected to contain a unique identifier, an EchoToken. This token will be returned in the response. It's recommended that you implement UUIDs - https://en.wikipedia.org/wiki/Universally_unique_identifier
Timestamps
As of pmsXchange v2, all timestamps will be qualified with a Timezone. All timestamps will be in GMT+0 time.
The GMT timezone does not apply to the dates provided for checkin/checkout, and daily rates. These are reported as provided by the original channel.