 involving an immediate site visit by the engineer. An escalation procedure has to be mutually agreed upon for initiating when a call-out is made. During an emergency situation the operator has the responsibility to initiate adequate efforts to carry out operation and maintenance procedures recommended by the vendor and to find a remedy for the faults. Basic first line maintenance is expected from the equipment operating personnel of the operator. The operator has to maintain an operational logbook in order to record the visible faults and changes tried by its staff to correct the faulty situation. On-Site Operations Support As a part of the deal the vendor may agree to provide on-site operation support for an initial first six months period, considering working days only and not round the clock support, which is covered separately. On-site support is provided with the aim of helping the operator rapidly ramp-up the operation and maintenance for the initial network system and also of providing initial support for routine technical operations for the first few months after commercially launching the network. This includes training the operator's personnel to whom the network operations will finally be handed over. The vendor's technical audit team as an integral part of this support service conducts a postlaunch performance audit, verifying the quality of the launched network and performance level of the end user services. The operator has to agree with the vendor regarding the timing and fragmentation of services, which has to be supplied as part of the on-site operation support service, well before the scheduled start of the period of operation support. Whether the operation support service is agreed or not the responsibility of running normal operation and maintenance of the network lies with the operator at all times. In order to perform their duties and obligations the on-site support personnel of the vendor have to be given free access to all locations at all times. The operator has to provide all such spare