What to know:

• Kraken could be the first of many to get direct access to the Federal Reserve payments system, analysts say after this week's approval of the crypto exchange's limited master account.

• This was an approval from the regional Fed bank in Kansas City, leaving some uncertainty about how Kraken's new status will relate to what the national-level Federal Reserve Board has been doing in writing a new "skinny" master account framework.

• The Kraken development surprised some in the crypto sector who'd been awaiting the policy process on the new system, but the traditional banking industry argued it represents a threat to the financial system.

The crypto industry keeps knocking down the barriers into the core U.S. financial system, and digital assets exchange Kraken's approval for a limited Federal Reserve account marked another such milestone that analysts think could be the first of a trend.