Network Services
This protocol uses both TCP and UDP and helps convert domain names (like www.example.com) into IP addresses so computers can find one another.
DNS (Domain Name System) — port 53 (TCP/UDP)
This protocol uses port 21 for its control connection and port 20 for its data connection to move files between hosts.
FTP: control on port 21 (TCP) and data on port 20 (TCP)
This protocol on port 25 is used to transfer email between mail servers over a network.
SMTP — port 25 (TCP)
HTTPS secures website traffic. Which port does HTTPS typically use?
HTTPS — port 443 (TCP)
The standard port for unsecure websites and web services; it's used by the protocol that transfers web pages and resources.
HTTP — port 80 (TCP)
A secure alternative to Telnet that provides an encrypted command-line connection to a server. What port does it commonly use?
SSH — port 22 (TCP)
A protocol used to retrieve email from a server by downloading messages to the client. It typically uses port 110; name the protocol.
POP (Post Office Protocol) — port 110 (TCP)
What is the primary difference between HTTP (port 80) and HTTPS (port 443) when it comes to security?
HTTPS encrypts traffic using TLS/SSL while HTTP sends data unencrypted
A set of three ports (137–139) provides support for older Windows networking features and name resolution over TCP/IP. Name this service family
NetBIOS over TCP/IP (ports 137–139) — provides legacy Windows networking features
Telnet provides an unsecure command-line connection to remote systems. Which port does Telnet use?
Telnet — port 23 (TCP
A more advanced mail retrieval protocol than POP that lets you read and manage mail on the server, often using port 143. What is it called?
IMAP (Internet Message Access Protocol) — port 143 (TCP)
LDAP operates on port 389. Briefly describe one common use of LDAP in networks.
LDAP is used to query user accounts, group membership, and directory entries (e.g., authenticating users or looking up email addresses)
This protocol listens on port 389 and is used to query information about network users and resources (often used by organizations to store user accounts).
LDAP — port 389 (TCP)
This protocol uses port 3389 to let users connect to a remote computer's graphical desktop.
RDP (Remote Desktop Protocol) — port 3389 (TCP)
When a user wants to access email while keeping messages on the server and supporting folders and flags (better for multiple devices), which protocol are they probably using (port 143)?
IMAP — port 143 (TCP)
Secure Shell (SSH) is commonly used for encrypted remote command-line connections. Which port does SSH use?
SSH — port 22 (TCP)
A client receives an IP address configuration from a server using this UDP port number; name the client-side port and the protocol.
DHCP Client — port 68 (UDP) (DHCP server uses port 67)
A protocol that enables Windows-compatible file and printer sharing on a local network and commonly uses port 445. Name the protocol.
SMB (Server Message Block) — port 445 (TCP)
Which ports or protocols are involved when an email client both sends mail via SMTP and retrieves it via IMAP? Provide the common port numbers for SMTP and IMAP.
SMTP: port 25 (TCP); IMAP: port 143 (TCP)
Windows-compatible file and printer sharing services on a local network.
SMB [ Server Message Blokc - Port 445