A working knowledge of the various operating systems (e.g. Windows, OS X, Linux, etc.) commonly deployed in enterprise networks, a conceptual understanding of Windows Active Directory is also required, and a working knowledge of network communications and routing protocols (e.g. TCP, UDP, ICMP, BGP, MPLS, etc.) and common internet applications and standards (e.g. SMTP, DNS, DHCP, SQL, HTTP, HTTPS, etc.).