In WCF, "wsHttpBinding" uses plain unencrypted texts when transmitting messages and is backward compatible with traditional ASP.NET web services (ASMX Web Services) ?

"wsHttpBinding" is secure (messages are encrypted while being transmitted), and transaction-aware. However, because this is a WS-* standard, some existing applications (for example: a QA tool) may not be able to consume this service. Hence, it is not completely backward compatible.