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NOTICE DATE: June 29, 2021

NOTICE TYPE: M-A060221-02 Operations

SHORT DESCRIPTION: Reminder - NAESB - Deprecation of all TLS versions except TLS 1.2 in the Production Environment

INTENDED AUDIENCE: All Market Participants that exchange NAESB transmissions with ERCOT

DAY AFFECTED: June 30, 2021

LONG DESCRIPTION: ERCOT will no longer support TLS 1.0, and will support TLS 1.2 exclusively for NAESB transactions in the Production Environment beginning June 30, 2021.

ACTION REQUIRED:  All Market Participants that exchange NAESB transmissions with ERCOT should confirm utilization of TLS 1.2 in NAESB transmissions both sent and received with ERCOT.

The Retail Market Test Environment User Guide can be used to test NAESB connectivity exchanges on an ad hoc basis at any of the times prescribed in the Retail Market Test Environment User Guide.

ADDITIONAL INFORMATION:  The "Retail Market Test Environment User Guide" can be found on the Texas Retail Market Testing page of ERCOT.com.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask].

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