A method of securely storing data on a network for access by devices (101, 102, 103) that belong to an authorized domain, the method comprising the steps of: establishing an authenticated channel between any domain member device and a candidate device that is to be included in the domain, over which channel authentication data of the candidate device is sent, said any domain member device being a domain master device; encrypting, at the domain master device, a confidential domain key with an encryption key of said candidate device and storing the encrypted domain key, thereby including the candidate device in the domain; and storing encrypted data on the network, which data is encrypted at any storing domain member device (101, 102, 103) by means of the domain key; the method characterised by: storing, on the network, a domain list comprising a domain identifier, the encryption key of each domain member device, a message authentication code including each encryption key and a domain authentication key derived from the domain key, and the encrypted domain key that corresponds to each domain member device; deleting, at the master device, when a domain member device is removed from the domain, a corresponding encryption key from the domain list; creating, at the master device, a confidential new domain key (K'); encrypting, at the master device, the new domain key with each remaining encryption key obtained from the domain list and producing a new message authentication code based on the new domain key and the remaining encryption keys; and creating, at the master device, an updated domain list based on the new domain key and storing the updated domain list on the network. establishing an authenticated channel between any domain member device and a candidate device that is to be included in the domain, over which channel authentication data of the candidate device is sent, said any domain member device being a domain master device; encrypting, at the domain master device, a confidential domain key with an encryption key of said candidate device and storing the encrypted domain key, thereby including the candidate device in the domain; and storing encrypted data on the network, which data is encrypted at any storing domain member device (101, 102, 103) by means of the domain key; the method characterised by: storing, on the network, a domain list comprising a domain identifier, the encryption key of each domain member device, a message authentication code including each encryption key and a domain authentication key derived from the domain key, and the encrypted domain key that corresponds to each domain member device; deleting, at the master device, when a domain member device is removed from the domain, a corresponding encryption key from the domain list; creating, at the master device, a confidential new domain key (K'); encrypting, at the master device, the new domain key with each remaining encryption key obtained from the domain list and producing a new message authentication code based on the new domain key and the remaining encryption keys; and creating, at the master device, an updated domain list based on the new domain key and storing the updated domain list on the network. storing, on the network, a domain list comprising a domain identifier, the encryption key of each domain member device, a message authentication code including each encryption key and a domain authentication key derived from the domain key, and the encrypted domain key that corresponds to each domain member device; deleting, at the master device, when a domain member device is removed from the domain, a corresponding encryption key from the domain list; creating, at the master device, a confidential new domain key (K'); encrypting, at the master device, the new domain key with each remaining encryption key obtained from the domain list and producing a new message authentication code based on the new domain key and the remaining encryption keys; and creating, at the master device, an updated domain list based on the new domain key and storing the updated domain list on the network.