Global variables are key/value pairs that you can use in flow services. At design time, instead of hard coding the values for variables, you can instruct Integration Server to use global variables.

To use global variable substitution in flow services, when assigning a value to a pipeline variable, you must specify the global variable as the value. You must also indicate that Integration Server should perform variable substitution. Then, at run time Integration Server substitutes the variables in the flow service with the values assigned to the respective global variables.

For example, you can define global variables for input parameters, such as serverhost or serverport, of pub.client* services. At design time, instruct Integration Server to use global variables defined for serverhost or serverport as the value of the corresponding variables in the pipeline. Then, at run time, Integration Server will substitute the variables in the flow service with the values assigned to serverhost or serverport global variables.

Using global variables makes it easy to change the value assigned to a pipeline variable. Instead of changing each mapping or flow service, you can change the value assigned to a variable by changing a single global variable.

For more information about global variable substitution, see webMethods Service Development Help.