Information Technology Reference
In-Depth Information
Table 4.2 Data Mapping Table
Source
Target
eBay.Order
TPC.COReq.Order
“eBay”
TPC.COReq.PartnerID
eBay.Order.(UserID, SecretID)
eBay.(UserID, SecretID)
TPC.(OrderID, UserID)
eBay.(Token, OrderID, UserID).(OrderID, UserID)
eBay.Token
eBay.(Token, OrderID, UserID).Token
eBay.OrderData
TPC.OrderData
In the eBay example, we have the data mapping shown in Table 4.2.
eBay and TPC stand for eBay and TPC services, respectively. Notations
such as eBay.Order stand for message Order of eBay. For complex
messages made up of multiple parts/elements, we use parentheses to
aggregate the multiple parts/elements into one single message; for
example, message eBay.(UserID, SercretID) stands for a message of
eBay, and this message is made up of two elements, that is, UserID and
SercretID;eBay.(Token, OrderID, UserID).Token stands for the ele-
ment Token in message (Token, OrderID, UserID)ofeBay.Inrow2of
Table 4.2, “eBay” stands for a constant string whose content is eBay.
Our approach assumes that the data mapping between two services
is accurate. It is easy to verify that the data mapping in Table 4.2 is
complete and accurate.
4.3.3 Mediator Existence Checking
In order to check whether there exists a mediator to glue two partially
compatible services, we introduce the concept of communicating reach-
ability graph (CRG). Its basic idea is to construct the reachability graph
of two services concurrently, using data mapping as a communication
mechanism. That is, when the source data are ready, their target should
be informed.
Given two SWF-nets N 1 and N 2 , and a data mapping I, their CRG is
a directed graph
M 2 . There are
two kinds of edges in CRG. One is an operation edge, that is,
E O ¼f
N 1 ;
N 2 ;
I
Þ¼ð
V
;
E
Þ
, where V
M 1
t
m 0
m 0 2
m 0 ;
h
m
;
t
;
ij
m
;
V and m
!
m 0 ¼
m 0
m 0 ¼
m 0 g
if t
2
T 1 ;
m 2 ; else if t
2
T 2 ;
m 1
Search WWH ::




Custom Search