Port and Protocols

Question	Answer
Port 20	FTP using TCP File Transfer Protocol Transfer Control Protocol to transfer information, unencrypted
Port 21	FTP using TCP File Transfer Protocol Transfer Control Protocol to establish & manage connection, unencrypted
Port 22	SSH & SFTP Secure Shell encrypted remote conn. between 2 devices over terminal emulator asymmetric encryption for conn. & auth.
Port 23	Telnet Teletype Network TCP port unencrypted remote conn. between 2 devices over terminal emulator used for initial setup of networking devices, including enabling SSH
Port 25	SMTP Simple Mail Transfer Protocol TCP port upload emails to email server
Port 49	TACACS+ TCP port encrypts username and password
Port 53	DNS & DNSSEC Domain Name System TCP port translates comp. name or website into full IP address works with FQDN
Port 67	DHCP Dynamic Host Configuration Protocol lease IP addresses, helps block spoofing & cache poisoning needs: IP address, subnet mask, default gateway address, DNS server address
Port 68	DHCP Dynamic Host Configuration Protocol lease IP addresses, statically or dynamically assigned Discover Offer Request Acknowledge
Port 69	TFTP Trivial File Transfer Protocol UDP port older method of transmitting small amounts of data unsecure
Port 80	HTTP Hyper Text Transfer Protocol TCP port unsecure
Port 88	Kerberos & EIGRP Enhanced Interior Gateway Routing Protocol native IP port Cisco proprietary encapsulates directly into IP datagrams
Port 89	OSPF Open Shortest Path First native IP port
Port 110	POP3 Post Office Protocol TCP port download emails to comp., data moves one direction, does not keep copy
Port 123	NTP Network Time Protocol UDP port Stratum 1 servers obtain UTC and provide that info to Stratum 2 servers considered "authoritative time"
Port 139	SMB Server Message Block sharing access to files, printers, serial ports and other resources on a network unsecure
Port 143	IMAPv4 Internet Message Access Protocol TCP port download emails to computer, keeps a copy unencrypted
Port 161	SNMP Simple Network Managing Protocol receives requests uses UDP "SNMP get-requests"
Port 162	SNMP Simple Network Managing Protocol responds to requests uses UDP "SNMP get-requests"
Port 179	BGP Border Gateway Protocol TCP port exterior routing protocol linking autonomous systems on the internet
Port 389	LDAP Lightweight Directory Access Protocol TCP and UDP port structure for organizing a companies personnel & resources into groups set permissions open source, other dir. based on LDAP
Port 443	HTTPS Hyper Text Transfer Protocol Secure TCP port
Port 445	CIFS & SMB Common Interest File System Server Message Block TCP port network file system protocols, bridging gap between diff. file systems & protocols file & printer sharing across network
Port 465	SMTPS TCP port no longer recommended
Port 500	IPSec UDP port transport mode - payload is encrypted tunnel mode - header and payload encrypted
Port 514	Syslog UDP port for logging and exchanging event messages on computers and network devices
Port 520	RIP Routing Information Protocol TCP port older routing protocol
Port 587	MSA Mail Submission Agents TCP port email clients use this port to submit messages to the SMTP server for transmission
Port 636	LDAPS secure LDAP Lightweight Directory Access Protocol TCP port
989/990	FTP ES "Explicit TLS" establishes an unsecure connection over port 21 then upgrades to secure connection to transfer user authentication using the AUTH TLS command 990 - connection \| 989 - data transfer
Port 993	IMAPS Internet Access Message Protocol TCP port
Port 995	POP3S Post Office Protocol
Port 1433	MS SQL TCP port
Port 1521	Oracle SQLnet TCP port
Port 1812/1813	RADIUS UDP port encrypts only the password
Port 2049	NFSv4 Network File System TCP port Unix and Windows allows computers on a network to exchange files
Port 3306	MySQL TCP port
Port 3389	RDP Remote Desktop Protocol TCP port provides an encrypted tunnel
Port 5060	SIP Session Initiation Protocol UDP port session management, creation, and tear-down sip:jane.bloggs@212.123.456 sip:support@telcosystem.xyz.com sip:22449832@telcosystem.xyz.com:6000
Port 5061	SIPS UDP port
Port 54323	PostgreSQL TCP port
Well Known Ports	0-1023
Registered Ports	1024-49151 used mostly for software and protocols that are not so universal
Dynamic/Private/Ephemeral	49152-65535 short-term and may be used for any purpose
Ethernet Protocol	for transferring data on a LAN layer 2 OSI model
Internet Protocol	set of rules for addressing and routing packets of data across a network layer 3 OSI model
STARTTLS	a secure implementation of SMTP "Explicit TLS" requires authentication before message submission

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	Created by Lyndsay Badding almost 2 years ago