Added SSHGuard.

SSHGuard written in C, protects other services in addition to SSH, works on BSD, GNU/Linux.

README.md

@@ -491,12 +491,13 @@ Comparison of NoSQL servers: http://kkovacs.eu/cassandra-vs-mongodb-vs-couchdb-v
   * [Glastopf](http://glastopf.org/) - A low-interaction web application honeypot to emulate vulnerabilities and gather attack data.
   * [Kippo](https://github.com/desaster/kippo) - A medium-interaction SSH honeypot, mostly used as a standalone SSH daemon with a configurable Filesystem sandbox.
   * [Linux Malware Detect](https://www.rfxn.com/projects/linux-malware-detect/) - A malware scanner for Linux designed around the threats faced in shared hosted environments.
+  * [Nmap](https://nmap.org) - Nmap is a free and open source utility for network discovery and security auditing.
   * [OSSEC](http://www.ossec.net/) - OSSEC is a HIDS that performs log analysis, FIM, rootkit detection, and much more.
   * [OSQuery](https://osquery.io/) - Query your servers status and info using a SQL like interface.
   * [pfSense](https://www.pfsense.org/) - Firewall and Router FreeBSD distribution.
   * [Snort](https://www.snort.org/) - Network intrusion prevention system (NIPS) and network intrusion detection system (NIDS).
   * [SpamAssassin](https://spamassassin.apache.org/) - A powerful and popular email spam filter employing a variety of detection technique.
-  * [Nmap](https://nmap.org) - Nmap is a free and open source utility for network discovery and security auditing.
+  * [SSHGuard](http://www.sshguard.net/) - A software to protect services in addition to SSH, written in C
 
 ## Service Discovery