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CompTIA Network+ 1.4 Cisco CCST Networking 1.5
TechKnowSurge Catalog Interactives Which Application Protocol Does the Job?
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Which Application Protocol Does the Job?

Which application layer protocol does each job?

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

About this interactive

From the lesson: - **DHCP** hands a device the settings it needs on this network: IP address, subnet mask, default gateway and DNS server. Move the laptop and the next network's DHCP server gives it new ones. - **DNS** translates the names users type, such as www.techknowsurge.com, into the IP addresses packets need. - **HTTP and HTTPS** transfer web pages, pictures and other resources between a server and a browser; HTTPS is the secure form. - **SMTP** sends mail: from the user's client to its server, and from server to server, even when the recipient is offline. - **POP3 and IMAP** let the recipient's mail client fetch that mail from the server when the user comes back online.

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

Application Layer
The topmost layer of the OSI model (Layer 7) that provides network services directly to end-user applications.
Dynamic Host Configuration Protocol
DHCP
A network protocol that automatically assigns IP addresses and other configuration parameters to devices on a network.
Domain Name System
DNS
A hierarchical naming system that translates human-readable domain names into IP addresses.
Hypertext Transfer Protocol
HTTP
An application-layer protocol that defines how web browsers and servers communicate to request and deliver web pages and other content, operating over TCP on port 80. HTTP transmits data in plaintext, which is why it has been largely replaced by HTTPS for sensitive content.
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.
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).
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).

Topics

Application Layer Dhcp Dns Http Email Interactive Categorize

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