SMTP (send mail transfer protocol)
Pop 3
465 is the default port number for SMTP. SMTP stands for Simple Mail Transfer Protocol. It is used for sending Emails over the network.
Network Control Protocol is uses to identify the Network layer protocol used in the packet
Class D
NTP(Network Time Protocol)
Simple Mail Transfer Protocol, is the technology used to send out email messages. It goes hand in hand with POP (Post Office Protocol) that is, typically, employed for receiving emails from a web server to an email program or an email client.
NTP (Network Time Protocol)
SNMP is the most widely used protocol for network monitoring
File transfer protocol
The most commonly used network protocol is Internet Protocol (IP), this is the protocol used within the Internet, this protocol is a derivative of TCP/IP Transmission Control Protocol/Internet Protocol. This is used in 99% of common corporate networks, the TCP components deals with efficiencies of network transmission. TCP/IP or IP overlays the common Ethernet networking topology.
SMTP is simple mail transport protocol. SNMP is simple network management protocol that is UDP based.