Important Ports - By Name Flashcards
File Transfer Protocol (FTP)
20/21 - TCP - Port 21 is the control port while port 20 is used to transfer files.
Secure Shell (SSH)
22 - TCP - Designed to transmit data through a remote connection.
SSH File Transfer Protocol
22 - TCP - A completely separate protocol from FTP (it is not compliant with FTP servers) that uses SSH to encrypt file transfers.
Simple Mail Transfer Protocol (SMTP)
587 - TCP - Internet mail protocol used to send outgoing mail from email clients to mail servers. old port used was 25.
TACACS+
49 - TCP - Cisco proprietary protocol used for authentication, authorization, and accounting (AAA) services.
Domain Name System (DNS)
53 - UDP - Used to associate IP addresses with domain names
Dynamic Host Configuration Protocol (DHCP)
67/68 - UDP - This network management protocol is used to assign multiple local private IP addresses from one public IPv4 address.
Hypertext Transfer Protocol (HTTP)
80 - TCP - Protocol used for websites and most internet traffic.
Kerberos
88 - TCP/UDP - Network authentication protocol that allows for communication over a non-secure network. Primarily uses UDP but can use TCP.
Post Office Protocol (POP)
110 - TCP - E-mail protocol that allows e-mail clients to communicate with e-mail servers. POP provides only one-way communication.
Network Time Protocol
123 - UDP - Low latency protocol used to synchronize timekeeping across a network.
Server Message Block (SMB)
445 - UDP - Windows proprietary protocol built on NetBIOS. Allows users to remotely access servers. Originally used port 139.
Internet Message Access Protocol (IMAP)
143, 993 - TCP - E-mail protocol used by e-mail clients to communicate with e-mail servers. Provides two way communication unlike POP.
Simple Network Management Protocol (SNMP)
161/ 162 - UDP - Protocol used to monitor and manage network devices on IP networks.
Lightweight Directory Access Protocol (LDAP)
389 - UDP - Used to manage and communicate with directories.
Hypertext Transfer Protocol Secure (HTTPS)
443 - TCP - Secure version of HTTP that uses TLS for encryption. Most websites use HTTPS instead of HTTP.
Secure Socket Tunneling Protocol (SSTP)
443 - TCP - Microsoft developed SSTP technology to replace the more insecure PPTP or L2TP/IPSec options available in Windows. SSTP uses TLS.
Server Message Block (SMB)
445 - TCP - Windows proprietary protocol built on NetBIOS. Allows users to remotely access servers.
Internet Protocol Security (IPSec) using ISAKMP
500 - UDP - Internet Protocol security achieved through the use of ISAKMP Internet Security Association and Key Management Protocol.
Simple Mail Transfer Protocol Secure (SMTPS)
587 - TCP - The secure version of SMTP. Uses TLS for encryption.
Lightweight Directory Access Protocol Secure (LDAPS)
636 - TCP - Secure version of LDAP that uses TLS for encryption.
File Transfer Protocol Secure (FTPS)
989/ 990 - TCP - Uses TLS for encryption. It can run on ports 20/21
Internet Message Access Protocol Secure (IMAPS)
993 - TCP - Secure version of IMAP that uses TLS for encryption.
Post Office Protocol 3 Secure (POP3S)
995 - TCP - Secure version of POP that uses TLS for encryption.
Remote Authentication Dial-In User Service (RADIUS)
1812, 1813 - UDP - Used to provide AAA for network services.
Remote Desktop Protocol (RDP)
3389 - TCP - This Windows proprietary protocol that enables remote connections to other computers.
Diameter
3868 - TCP - Developed as an upgrade to Radius.
Secure Real Time Protocol (SRTP)
5004 - UDP - SRTP replaced RTP and is a protocol used to stream audio and video communication using UDP.
Transmission Control Protocol (TCP)
N/A - One of two main protocols of the Internet Protocol (IP) suite used to transmit data over an IP network.� TCP provides error checking to ensure packets are not lost in transit. - Layer 4 (Transport Layer)
User Datagram Protocol (UDP)
N/A - The second main protocol in the IP suite that transmits datagrams in a best effort method.� UDP does not include error checking. - Layer 4 (Transport Layer)
Point to Point Tunneling Protocol (PPTP)
1723 - Layer 4 (Transport Layer) - TCP - Based on PPP. Deprecated protocol for VPNs.
Layer 2 Tunneling Protocol (L2TP)
1701 - layer 2 (Data Link Layer) - UDP - Used to create point to point connections, like VPNs over a UDP connection. Needs IPSec for encryption. Designed as an extension to PPTP.� Operates at the data link layer but encapsulates packets at the session layer.
Point to Point Tunneling Protocol (PPTP)
1723 - layer 2 (Data Link Layer) - UDP - Based on PPP. Deprecated protocol for VPNs.
