k roll-out is completed, with network elements fully commissioned, integrated, opera- tional and accepted by the operator or taken into commercial use, then the Care phase starts. A mature network operator can decide to do many operations on their own and restrict the vendor to supply only hardware replacements and guarantee. A normal care agreement consists of four categories of services: Care management Hardware services (repairs and swap) Roll-Out Network Project Management Software maintenance services (software releases, fault management, change notes) Technical support service, including help desk, emergency support services and online services Terms and Conditions The care agreement sets out terms and conditions under which the vendor performs all or part of the care services in respect of the equipment supplied by them. An overview of a care agreement gives a description of terms and conditions under which the operator has agreed to purchase the after-sales support services. In case the operator defaults a payment by more than a set amount of days, e.g. 15 days, then the vendor has the right to issue a written notice to the Operator attention that such action can lead to cancellation of the care agreement. Conversely, if the operator has raised a high priority list of problems to be solved, which is directly affecting daily operations and customers, and the vendor is unable to provide a remedial action within a preset period of time, e.g. 30 days, then the operator can issue a written notice to the vendor, attention to the fact that such default action or lack of required support can lead to penalty clauses or liquidity damages or even cancellation of contract. However, the operator has the customer's privilege of cancelling this contract if the vendor defaults on their performance or fails to abide by the agreed terms and conditions. Fees and Payment Normally the operator purchases 'care services' annually in advance and the vendor invoices them quarterly in advance, unless specified otherwise. Other add