9.6.1 Cryptographic Library layer

The Cryptographic Library layer, can currently be used either with libgcrypt or libnettle, each of one has its advantages and some disadvantages. Libgcrypt is a self-contained library, pretty broad in scope that supports many algorithms. In some processors like VIA, it will also use the available crypto instruction set hence providing performance benefit comparing to plain software implementation. Libnettle provides only software implementation of the basic algorithms required in TLS, and is on average 30% faster that libgcrypt on almost all algorithms. For this reason libnettle is library used by default in GnuTLS.