SSIS enhancements in SQL Server 2012 brings a brand new deployment model for SSIS project deployment. This new deployment model is called Project Deployment Model and unlike the Legacy Deployment Model where each package was a single unit of deployment, this new model creates a deployment packet containing everything (packages and parameters) needed for deployment in a single file with an ispac extension and hence streamlines the deployment process.

Apart from handling the deployment issues, managing the configuration file for each environment for each package was also a pain in the Legacy Deployment model. The new Project Deployment Model includes Project/Package Parameters, Environments, Environment variables and Environment references.

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