Cyberkraft Security+ 601 Ports and Protocols Reference Sheet

FTP

File Transfer Protocol

Ports 20 and 21
Port 21 is the control port. Port 20 is used to transfer files.

SSH

Secure Shell

Port 22
Designed to transmit data through a remote connection.

SFTP

SSH File Transfer Protocol

Port 22
A completely separate protocol from FTP that uses SSH to encrypt file transfers. NOT compliant with FTP servers.

TACACS+

Terminal Access Controller Access-Control System Plus

Port 49
Cisco proprietary protocol used for Authentication, Authorization, and Accounting (AAA) services.

DNS

Domain Name System

Port 53
Used to associate IP addresses with domain names.

DHCP

Dynamic Host Configuration Protocol

Ports 67 and 68
Assigns local IP addresses to devices on a network. Creates multiple private IP addresses from one public IPv4 address.

HTTP

Hypertext Transfer Protocol

Port 80
Protocol used for websites and most internet traffic.

Kerberos

Kerberos

Port 88
Network authentication protocol that allows communication over a non-secure network.

POP3

Post Office Protocol version 3

Port 110
Email protocol that allows email clients to communicate with email servers. Provides only one-way communication.

IMAP

Internet Message Access Protocol

Ports 143 and 993
Email protocol used by email clients to communicate with email servers. Provides two-way communication (unlike POP3).

SNMP

Simple Network Management Protocol

Ports 161 and 162
Protocol used to monitor and manage network devices on IP networks.

LDAP

Lightweight Directory Access Protocol

Port 389
Used to manage and communicate with directories.

HTTPS

Hypertext Transfer Protocol Secure

Port 443
Secure version of HTTP that uses TLS for encryption. Most websites use HTTPS instead of HTTP.

LDAPS

Lightweight Directory Access Protocol Secure

Port 636
Secure version of LDAP that uses TLS for encryption.

FTPS

File Transfer Protocol Secure

Ports 989 and 990
Uses TLS for encryption. Can also run on ports 20/21 but sometimes allocated to 989/990.

IMAPS

Internet Message Access Protocol Secure

Port 993
Secure version of IMAP that uses TLS for encryption.

POP3S

Post Office Protocol 3 Secure

Port 995
Secure version of POP3 that uses TLS for encryption.

RADIUS

Remote Authentication Dial-In User Service

Ports 1812 and 1813
Used to provide Authentication, Authorization, and Accounting (AAA) for network services.

Diameter

Diameter

Port 3868
Developed as an upgrade to RADIUS.

SRTP

Secure Real-time Transport Protocol

Port 5004
Replaced RTP. Used to stream audio and video communication using UDP.

L2TP

Layer 2 Tunneling Protocol

Port 1701
Used to create point-to-point connections like VPNs over UDP. Needs IPsec for encryption.

TCP

Transmission Control Protocol

One of two main protocols in the Internet Protocol suite. Provides error checking to ensure packets are not lost in transit.

UDP

User Datagram Protocol

The second main protocol in the IP suite. Transmits datagrams in a best-effort method. Does NOT include error checking.

PPTP

Point-to-Point Tunneling Protocol

Port 1723
Based on PPP. Deprecated protocol for VPNs.

RDP

Remote Desktop Protocol

Port 3389
Windows proprietary protocol that provides a remote connection between two computers.