Layered Service Provider, an acronym for LSP, is an existing Microsoft Windows feature from Windows 98 and removed from Windows Server 2012 Winsock 2 Service Provider Interface (SPI) .

The tiered service provider is a DLL that uses the Winsock API to be inserted into the TCP / IP stack. Once in the heap, a Layered Service Provider can insert and modify Internet traffic and outputs. This allows you to process all TCP / IP traffic that takes place between the Internet and applications that are accessing the Internet (such as a web browser, an email client, etc.).

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