Exhibit 4.23

ASSIGNMENT

For value received, Silicon Valley Bank hereby sells, assigns and transfers unto:

Name: Silicon Valley Bancshares

Address: 3003 Tasman Drive (HA-200)

Santa Clara, CA 95054

TaxID:

that certain Warrant to Purchase Stock issued by Optical Solutions, Inc. (the “Company”), on August 16, 2004 (the “Warrant”) together with all rights, title and interest therein.

Date:     8/19/04    

By its execution below, and for the benefit of the Company, Silicon Valley Bancshares makes each of the representations and warranties set forth in Article 4 of the Warrant as of the date hereof.