|  | 9.1 | The TCP/IP Protocol Suite
| 9.1.2 | TCP/IP protocol stack and the application layer
The application layer supports addressing protocols and network management. It also has protocols for file transfer, e-mail, and remote login. DNS (Domain Name System) is a system used in the Internet for translating names of domains and their publicly advertised network nodes into addresses. WINS (Windows Internet Naming Service) is a Microsoft-developed standard for Microsoft Windows NT that automatically associates NT workstations with Internet domain names. HOSTS is a file created by network administrators and maintained on servers. They are used to provide static mapping between IP addresses and computer names. POP3 (Post Office Protocol) is an Internet standard for storing e-mail on a mail server until you can access it and download it to your computer. It allows users to receive mail from their inboxes using various levels of security. SMTP (Simple Mail Transport Protocol) governs the transmission of e-mail over computer networks. It does not provide support for transmission of data other than plain text. SNMP (Simple Network Management Protocol) is a protocol that provides a means to monitor and control network devices, and to manage configurations, statistics collection, performance and security. FTP (File Transfer Protocol) is a reliable connection-oriented service that uses TCP to transfer files between systems that support FTP. It supports bi-directional binary file and ASCII file transfers. TFTP (Trivial File Transfer Protocol) is a connectionless unreliable service that uses UDP to transfer files between systems that support the TFTP. It is useful in some LANs because it operates faster than FTP in a stable environment. HTTP (Hypertext Transfer Protocol) is the Internet standard that supports the exchange of information on the World Wide Web, as well as on internal networks. It supports many different file types, including text, graphic, sound, and video. It defines the process by which Web browsers originate requests for information to send to Web servers. - The troubleshooting protocols Telnet is a standard terminal emulation protocol used by clients for the purpose of making remote terminal connections to Telnet server services; enables users to remotely connect to routers to enter configuration commands. PING (Packet Internet Groper) is a diagnostic utility used to determine whether a computer is properly connected to devices/Internet. Traceroute is a program that is available on many systems, and is similar to PING, except that traceroute provides more information than PING. Traceroute traces the path a packet takes to a destination, and is used to debug routing problems. There are also a few Windows-based protocols that you should be familiar with: NBSTAT -- a utility used to troubleshoot NetBIOS name resolution; used to view and remove entries from the name cache. NETSTAT -- a utility that provides information about TCP/IP statistics; can be used to provide information about the status of TCP/IP connections and summaries of ICMP, TCP, and UDP. ipconfig/winipcfg -- utilities used to view current network settings for all ip (nic) adapters on a device; can be used to view the MAC address, IP address, and gateway.