How are network policies defined in Snowflake?

A Snowflake network policy is a security feature that controls access to an account based on the user's source IP address. Administrators can create policies that specify a list of allowed IP addresses (a whitelist) and/or a list of blocked IP addresses (a blacklist). When a network policy is activated for an account or a specific user, Snowflake only permits connection attempts from IP addresses included in the allowed list and not present in the blocked list. This provides a granular, network-level layer of security for the entire account.

A. This is incorrect. Network routing within Snowflake's infrastructure is managed internally by Snowflake and is not configurable by customers through network policies.
B. This is incorrect. Rules dictating how users can use an account are managed through Snowflake's Role-Based Access Control (RBAC) framework, not network policies.
C. This is incorrect. Transferring data between accounts is managed through features like Secure Data Sharing or database replication, not network policies.

1. Snowflake Documentation: Network Policies.

Section: Overview

Content: "Snowflake supports network policies to allow or deny access to a single IP address or a list of addresses... A network policy consists of a list of allowed IP addresses and a list of blocked IP addresses."

2. Snowflake Documentation: Managing Network Policies.

Section: Creating Network Policies

Content: "You can create a network policy to allow or deny access to a list of IP addresses... Use the CREATE NETWORK POLICY command to create a new network policy." This section demonstrates the syntax CREATE NETWORK POLICY mypolicy ALLOWEDIPLIST = ('192.168.1.0/24', '192.168.255.100') BLOCKEDIPLIST = ('192.168.1.99');, which directly supports the definition in option D.