Editing Secure Shell (section)

===Version 2===
In 2006, after being discussed in a working group named "secsh",<ref>[https://datatracker.ietf.org/wg/secsh/documents/ IETF (Internet Engineering Task Force): datatracker for secsh ]</ref> a revised version of the SSH protocol, '''SSH-2''' was adopted as a standard.<ref name="rfc-ssh">[https://datatracker.ietf.org/doc/html/rfc4252 RFC4252: The Secure Shell (SSH) Authentication Protocol, Jan 2006]</ref> This version offers improved security and new features, but is not compatible with SSH-1. For example, it introduces new key-exchange mechanisms like [[Diffie–Hellman key exchange]], improved [[data integrity]] checking via [[message authentication code]]s like [[MD5]] or [[SHA-1]], which can be negotiated between client and server. SSH-2 also adds stronger encryption methods like [[Advanced_Encryption_Standard|AES]] which eventually replaced weaker and compromised ciphers from the previous standard like [[Triple DES|3DES]].<ref>[https://docstore.mik.ua/orelly/networking_2ndEd/ssh/ch03_05.htm O'Reily: Secure Shell, The Definitive Guide]</ref><ref>[https://datatracker.ietf.org/doc/html/rfc4250#page-16 RFC4250: The Secure Shell (SSH) Protocol: Assigned names, Jan 2006, page 16]</ref><ref name="rfc-ssh">[https://datatracker.ietf.org/doc/html/rfc4252 RFC4252: The Secure Shell (SSH) Authentication Protocol, Jan 2006]</ref> New features of SSH-2 include the ability to run any number of [[Unix shell|shell]] sessions over a single SSH connection.<ref>{{cite web|url=http://www.snailbook.com/faq/ssh-1-vs-2.auto.html|title=SSH Frequently Asked Questions|url-status=live|archive-url=https://web.archive.org/web/20041010035705/http://www.snailbook.com/faq/ssh-1-vs-2.auto.html|archive-date=2004-10-10 }}</ref> Due to SSH-2's superiority and popularity over SSH-1, some implementations such as libssh (v0.8.0+),<ref>{{cite web|url=https://www.libssh.org/2018/08/10/libssh-0-8-0/|title=libssh}}</ref> [[Lsh]]<ref>{{cite web|url=http://www.lysator.liu.se/~nisse/lsh/|title=A GNU implementation of the Secure Shell protocols|url-status=live|archive-url=https://web.archive.org/web/20120204035753/http://www.lysator.liu.se/~nisse/lsh/|archive-date=2012-02-04}}</ref> and [[Dropbear (software)|Dropbear]]<ref>{{cite web|url=https://matt.ucc.asn.au/dropbear/dropbear.html|title=Dropbear SSH|url-status=live|archive-url=https://web.archive.org/web/20111014091250/http://matt.ucc.asn.au/dropbear/dropbear.html|archive-date=2011-10-14}}</ref> eventually supported only the SSH-2 protocol.