Security+ 701 Ports and Protocols

Vocabulary flashcards covering common Security+ ports and protocols, their purposes, and associated port numbers.

File Transfer Protocol (FTP)

Transfers files (legacy). Uses TCP 21/20.

Secure Shell (SSH)

Secure remote command line. Uses TCP 22.

SSH File Transfer Protocol (SFTP)

Secure file transfer over SSH. Uses TCP 22.

Simple Mail Transfer Protocol (SMTP)

Sends outgoing email. Uses TCP 25.

TACACS+

Cisco's Identity (AAA) protocol. Uses TCP 49.

Domain Name System (DNS)

Maps names to IP addresses. Uses UDP 53.

Dynamic Host Configuration Protocol (DHCP)

Assigns device IP addresses. Uses UDP 67/68.

Hypertext Transfer Protocol (HTTP)

Unencrypted web traffic. Uses TCP 80.

Kerberos

Ticket-based network authentication. Uses UDP 88.

Post Office Protocol version 3 (POP3)

Retrieves email (one-way). Uses TCP 110.

Network Time Protocol (NTP)

Synchronizes device time. Uses UDP 123.

Server Message Block (SMB) over NetBIOS

Windows file sharing (old). Uses UDP 139.

Internet Message Access Protocol (IMAP)

Retrieves/manages email (two-way). Uses TCP 143/993.

Simple Network Management Protocol (SNMP)

Monitors network devices. Uses UDP 161/162.

Lightweight Directory Access Protocol (LDAP)

Directory service for querying info. Uses UDP/TCP 389.

Hypertext Transfer Protocol Secure (HTTPS)

Encrypted web traffic. Uses TCP 443.

Secure Socket Tunneling Protocol (SSTP)

Microsoft VPN tunneling. Uses TCP 443.

Server Message Block (SMB) direct over TCP

Windows modern file sharing. Uses TCP 445.

IPSec with ISAKMP/IKE

Secures IP traffic. Key exchange on UDP 500.

Simple Mail Transfer Protocol Secure (SMTPS)

Secure outgoing email (SMTP with TLS). Uses TCP 587.

Lightweight Directory Access Protocol Secure (LDAPS)

Secure directory service (LDAP with TLS). Uses TCP 636.

File Transfer Protocol Secure (FTPS)

Secure FTP with TLS. Uses TCP 989/990.

Internet Message Access Protocol Secure (IMAPS)

Secure IMAP with TLS. Uses TCP 993.

Post Office Protocol 3 Secure (POP3S)

Secure POP3 with TLS. Uses TCP 995.

Remote Authentication Dial-In User Service (RADIUS)

Open Identity (AAA) protocol. Uses UDP 1812/1813.

Remote Desktop Protocol (RDP)

Microsoft remote desktop access. Uses TCP 3389.

Diameter

Next-gen Identity (AAA) protocol. Uses TCP 3868.

Secure Real-Time Transport Protocol (SRTP)

Encrypted voice/video streaming. Uses UDP 5004.

Transmission Control Protocol (TCP)

Reliable, ordered data delivery. Layer-4, connection-oriented.

User Datagram Protocol (UDP)

Fast, unordered data delivery. Layer-4, connectionless.

Layer 2 Tunneling Protocol (L2TP)

VPN tunneling. Uses UDP 1701 for tunneling; relies on IPSec.

Point-to-Point Tunneling Protocol (PPTP)

Old, insecure VPN protocol. Uses TCP/UDP 1723.

OSI Layer 1: Physical

Moves bits across cables and signals (wires, fiber, radio)

OSI Layer 2: Data Link

Frames data for delivery on the same network. Uses MAC addresses.

OSI Layer 3: Network

Routes data between networks using IP addresses.

OSI Layer 4: Transport

Breaks data into chunks. Uses ports. TCP = reliable, UDP = fast.

OSI Layer 5: Session

Manages connections. Starts, keeps, and ends sessions.

OSI Layer 6: Presentation

Translates data so apps understand it. Handles encryption & formatting.

OSI Layer 7: Application

Where users interact. Protocols like HTTP, FTP, DNS run here.