Brownfield Connectivity Services - Connectivity Maintenance BF. When concluding a Connectivity Maintenance contract, Siemens will keep the connection provided for the customer always up-to-date by providing hotfixes and service packs. If nevertheless a problem or question regarding the infrastructure installed by Siemens arises, the customer can use the Siemens hotline, which is Included in the contract. Further contractual conditions are can be found in the offer.