#### Authenticated RPC and Protection Levels

The authenticated RPC facility provides several levels of protection so that applications can control tradeoffs between security and performance. Following is a summary of some of the protection levels that an application using authenticated RPC may specify:

· Connect level

Performs authentication only when a client and server establish a relationship (or connection)

· Call level

Attaches a verifier to each client call and server response that protects the system-level metadata of every RPC call (but not the application-level data)

· Packet-integrity level

In addition to protecting metadata, ensures the integrity of the application-level data (RPC call and return parameters) transferred between two principals, that is, that none of it has been modified in transit

· Packet-privacy level

In addition to protecting metadata and integrity, encrypts all application-level data, thus guaranteeing its confidentiality

Refer to the discussion of authenticated RPC in Basic RPC Routine Usage and RPC and Other DCE Components for complete information about protection levels.

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