A network architect is designing a solution for zero-touch provisioning (ZTP) of new branch office routers. The solution needs to dynamically fetch initial configuration files and software images from a central server based on the device's serial number or MAC address. Which protocol is commonly used by network devices to discover the provisioning server and download necessary files during ZTP?
- ABGP (Border Gateway Protocol)
- BOSPF (Open Shortest Path First)
- CDHCP (Dynamic Host Configuration Protocol)
- DDNS (Domain Name System)
Show answer & explanationAnswer & explanation
Correct answer: C. DHCP (Dynamic Host Configuration Protocol)
DHCP is a crucial component in ZTP. Network devices use DHCP to obtain an IP address, and often, DHCP options (like option 67 for boot filename or option 150 for TFTP server address) are used to point the device to a provisioning server (e.g., TFTP, HTTP) from which it can download its initial configuration or software image.
Why the other options are wrong
- A. BGP is a routing protocol used for exchanging routing information between autonomous systems, not for device provisioning.
- B. OSPF is an interior gateway routing protocol, not for initial device provisioning and file discovery.
- D. DNS translates domain names to IP addresses, but DHCP is typically used to discover the initial provisioning server itself.
DHCP in ZTP
In Zero-Touch Provisioning (ZTP), DHCP (Dynamic Host Configuration Protocol) is used by new network devices to obtain an IP address and discover the location of a provisioning server (e.g., TFTP, HTTP) via DHCP options, which then provides initial configuration or software images.
- Assigns IP address.
- Provides network configuration.
- Uses DHCP options (e.g., 67, 150).
- Points device to provisioning server.
Memory trick: DHCP is the 'DOORway' for ZTP to get network access and find its config.