  Web service technology has gained more important role in developing
distributed applications and systems on the Internet. Rapid growth of published
Web services makes their discovery more and more difficult. There exist many
web services which exhibit similar functional characteristics. It is imperative
to provide service consumers with facilities for selecting required web
services according to their non-functional characteristics or QoS. The
QoS-based web service discovery mechanisms will play an essential role in SOA,
as e-Business applications want to use services that most accurately meet their
requirements. However, representing and storing the values of QoS attributes
are problematic, as the current UDDI was not designed to accommodate these
emerging requirements. To solve the problems of storing QoS in UDDI and
aggregating QoS values using the tModel approach. The aim is to study these
approaches and other existing QoS tModel representation for their efficiency
and consistency in service discovery. This paper discusses a broad range of
research issues such as web service discovery or web service selection based on
QoS in the E-Business domain.
