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CompTIA Network+ 1.4 Cisco CCST Networking 1.5
TechKnowSurge Catalog Interactives Type the Port Number
InteractiveNetworkFree

Type the Port Number

Console, file transfer and email protocols and their secure versions: type the port.

⚑ Complete this interactive to capture a CTF flag worth 5 points.

About this interactive

The lesson's ports (IANA well-known assignments): | Protocol | Port | Transport | Note | | --- | --- | --- | --- | | Telnet | 23 | TCP | Console, not encrypted | | SSH | 22 | TCP | Console, encrypted | | FTP | 21 control, 20 data | TCP | Not encrypted | | SFTP | 22 | TCP | Runs over SSH | | FTPS | 990 control, 989 data | TCP | FTP over TLS (called FTP over SSL) | | TFTP | 69 | UDP | No login, simple transfers | | SMTP | 25 | TCP | Sends and relays mail | | Mail submission | 587 | TCP | Clients send mail, secured with TLS | | POP3 | 110 | TCP | Downloads mail | | POP3S | 995 | TCP | POP3 over TLS | | IMAP | 143 | TCP | Syncs mail | | IMAPS | 993 | TCP | IMAP over TLS | | DNS | 53 | UDP and TCP | Name resolution | The lesson's note: SSL's name stuck to these protocols, but they are secured with TLS today.

What you'll learn

Aligned to

CompTIA Network+
1.4 Explain common networking ports, protocols, services, and traffic types.
Cisco CCST Networking
1.5 Describe common network applications and protocols

Key terms

Well-Known Ports
Port numbers ranging from 0 to 1023 that are reserved for standard, widely used services and protocols.
Port
A logical endpoint for communication in a network, identified by a number that specifies a particular service or application.
Secure Shell
SSH
A cryptographic network protocol that provides secure remote login and command execution over an unsecured network.
File Transfer Protocol
FTP
A standard network protocol used to transfer files between a client and a server over a TCP network.
Simple Mail Transfer Protocol
SMTP
A TCP-based application-layer protocol used to send email messages between mail servers and from mail clients to outbound mail servers, typically on port 25 (server-to-server) or port 587 with TLS (client submission). SMTP only handles sending mail; retrieval is handled by separate protocols such as IMAP or POP3.
Internet Message Access Protocol
IMAP
A TCP-based email protocol that provides dynamic synchronization between a mail server and client, operating on port 143 (insecure) or port 993 (over SSL/TLS).
Post Office Protocol version 3
POP3
A TCP-based email retrieval protocol that downloads messages from a mail server to a local client, operating on port 110 (insecure) or port 995 (over SSL/TLS).

Topics

Ports Well Known Ports Ssh Ftp Email Interactive Calculation

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