Article 4 of this Agreement. MAINTENANCE FEES: LICENSED TECHNOLOGY FOR THE BASIC SERVICES SPECIFIED IN EXHIBIT A The Maintenance Fee after the expiry of the Warranty period shall be $20,000 per year, starting from the date after the Warranty period (Contract Year), renewable at the end of each Contract Year. In the event that during the four consecutive calendar quarters which begin immediately after the start of a Contract Year, LICENSEE completes payments to D2 of one hundred thousand dollars in Runtime License Fees under this Agreement, D2 will apply a credit equaling to 100% of the Maintenance Fee against the Runtime License Fees of that Contract Year. In the event that LICENSEE exercises the Buy Out option for Runtime License Fees, there shall be no Maintenance Fee for the first three years after the expiry of the Warranty period. RUNTIME LICENSE FEES: LICENSED TECHNOLOGY FOR BASIC SERVICES SPECIFIED IN EXHIBIT A AND SIMPLE CONFERENCING TECHNOLOGY A runtime license fee shall be paid for each SRM in the Licensee Product (Exhibit B) which contains the Licensed Technology for Basic Services and simple conferencing which does not require network echo cancellation technology (Exhibit A) sold by LICENSEE. Licensee Products which do not run the Licensed Technology are not subject to runtime license fees. The runtime license fee is based on the number of ports of service that a customer can expect the SRM to provide. As such, this runtime license fee calculation may be used for an SRM with any number of DSP processors (DSPs), with any MIPS Software License D2 Technologies, Inc. and Maintenance Agreement August 4, 1997 CONFIDENTIAL 45 performance rating, as long as it is from the TI TMS320C54x, TMS320C55x, or TMS320C6x processor family. Fee_per_SRM = Fee_per_Port * DSPs_per_SRM * Average_Ports_per_DSP Where: Fee_per_SRM is the runtime license fee