SSH(Secure Shell)是什么呢？

  SSH(Secure Shell)是什么呢？权势巨子的说法是：‘Secure shell is a de facto standard for remote logins and encrypted file transfers。’。SSH由芬兰赫尔辛基DX的Tatu Ylonen在1995年创造，其次要目标就是通过认证和加密手段在互联网供给一条平安的毗连(其实不仅是Terminal)，默认运行于TCP 22号端口。

  目前有两种协议版本：SSH-1和SSH-2。

要理解SSH起首要大白它的几把Key: Host Key / Server Key / Session Key / User Key

详细见下表: Name Lifetime Created by Type Purpose Host key Persistent Administrator Public Identify a server/machine Server key One hour Server Public Encrypt the session key(SSH1 only) Session key One session Client (and server) Secret Protect communications User key Persistent User Public Identify a user to the serve。