Question

what is the primary function of cisco discovery protocol (cdp)?

a to provide a secure tunnel for data transmission
b to encrypt data traffic between cisco devices
c to discover information about directly connected cisco devices
d to assign ip addresses to devices on a network

Explanation:

Analyze the protocol purpose

Cisco Discovery Protocol (CDP) is a proprietary Layer 2 link-local protocol developed by Cisco Systems. It is designed to share information between directly connected Cisco network devices (such as routers, switches, and IP phones).

Evaluate the options

• Option A describes a VPN or tunneling protocol (e.g., IPsec, GRE), which is incorrect.
• Option B describes encryption protocols (e.g., MACsec, IPsec), which is incorrect as CDP transmits information in plaintext.
• Option C describes neighbor discovery, which is the primary function of CDP (sharing device IDs, address info, port IDs, platform, etc., with directly connected neighbors).
• Option D describes DHCP or SLAAC, which is incorrect.

Answer:

• A To provide a secure tunnel for data transmission
• B To encrypt data traffic between Cisco devices
• C To discover information about directly connected Cisco devices (Correct answer)
• D To assign IP addresses to devices on a network