Exhibit 99.1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(1)(iii) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a Statement on Schedule 13D (including additional amendments thereto) with respect to the shares of Common Stock, $0.0001 par value, of A10 Networks, Inc., a Delaware corporation. This Joint Filing Agreement shall be filed as an Exhibit to such Statement.

Dated: January 29, 2018 

VIEX Opportunities Fund, LP – Series One
By:	VIEX GP, LLC General Partner
By:	/s/ Eric Singer
	Name:	Eric Singer
	Title:	Managing Member

VIEX GP, LLC
By:	/s/ Eric Singer
	Name:	Eric Singer
	Title:	Managing Member

VIEX Special Opportunities Fund II, LP
By:	VIEX Special Opportunities GP II, LLC General Partner
By:	/s/ Eric Singer
	Name:	Eric Singer
	Title:	Managing Member

VIEX Special Opportunities GP II, LLC
By:	/s/ Eric Singer
	Name:	Eric Singer
	Title:	Managing Member

VIEX Capital Advisors, LLC
By:	/s/ Eric Singer
	Name:	Eric Singer
	Title:	Managing Member

/s/ Eric Singer

Eric Singer