fcbb435a_ofessional_Growth__Leadership___Description
[Title] Connect-Disconnect [Category] Operations [Last Updated] 9/7/2006 [Description] 
When dealing with a duplex contract, every operation carries with it the callback reference. In most applications the client also would like to explicitly start or stop receiving callbacks. You can do that by adding a Connect/Disconnect methods to the contract, as shown in The download.
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