# phpman > ri > Net::SSH::Transport::HMAC::SHA2_256_Etm

## [Net::SSH::Transport::HMAC::SHA2256Etm](https://www.chedong.com/phpMan.php/perldoc/Net%3A%3ASSH%3A%3ATransport%3A%3AHMAC%3A%3ASHA2256Etm/markdown) < [Net::SSH::Transport::HMAC::Abstract](https://www.chedong.com/phpMan.php/perldoc/Net%3A%3ASSH%3A%3ATransport%3A%3AHMAC%3A%3AAbstract/markdown)

(from /home/chedong/.local/share/rdoc)
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The SHA-256 Encrypt-Then-Mac HMAC algorithm. This has a mac and key
length of 32, and uses the SHA-256 digest algorithm.
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