SOFT: Apache, nginx, FTP, SSH, VPN, MySQL, Firewalls( Cisco, iptables, ipfw, pf, Windows Firewall), exim, postfix,
sendmail, nagios, dude, squid, cacti, OpenVZ, Virtuozzo, XEN, KVM, Cpanel, Plesk, Direct Admin, ISPManager,  CloudLinux, Ruby, Rails. PROTOCOLS: OSPF, RIP(v1,v2), IS-IS, EIGRP HARDWARE: Cisco, Juniper, Riorey(Anti DDoS), MikroTik, TP-Link, HP Servers, SuperMicro Servers, DELL Servers