A cellular device comprising: a card comprising storage that stores a provisioning profile comprising a shared International Mobile Subscriber Identity, IMSI, and a shared secret key, wherein the shared IMSI and the shared secret key are also stored by a Mobile Network Operator, MNO, apparatus operated by an MNO to service a cellular network provided by the MNO, the card further comprising instructions that, when executed by a processor of the cellular device or the card, dynamically generate, and store to the storage, the shared IMSI and the shared secret key; the provisioning profile in the card, including the shared IMSI and the shared secret key, having been assigned to a plurality of other cards to enable other cellular devices comprising the respective cards to complete an authentication procedure via the cellular network with the MNO apparatus using the same shared IMSI and the same shared secret key, wherein the authentication procedure is compliant with a standard cellular communication protocol; a radio configured to connect to cellular networks; and the storage storing additional instructions that, when the cellular device is operating, are executed by the processor to cause the processor to use the shared IMSI and the shared secret key to perform the authentication procedure with the MNO apparatus to establish a channel, via the radio, with the cellular network; wherein the storage stores a master key, wherein the master key is stored by the other cellular devices, and wherein when the processor dynamically generates the shared IMSI and the shared secret key, the master key is used to generate the shared IMSI and the shared secret key; wherein the instructions to cause the processor to dynamically generate the shared IMSI and the shared secret key, and to perform the authentication procedure with the MNO apparatus comprise selecting the shared IMSI from a predetermined range; dynamically computing the shared secret key as a function of the shared IMSI and the master key; using the dynamically generated shared secret key and the selected shared IMSI to authenticate with the MNO; selecting, if there is a collision due to the selected shared IMSI being in use, another shared IMSI and repeating the selecting, computing, and using steps; and using the established channel on the MNO's network to provision the cellular device with a subscriber profile. a card comprising storage that stores a provisioning profile comprising a shared International Mobile Subscriber Identity, IMSI, and a shared secret key, wherein the shared IMSI and the shared secret key are also stored by a Mobile Network Operator, MNO, apparatus operated by an MNO to service a cellular network provided by the MNO, the card further comprising instructions that, when executed by a processor of the cellular device or the card, dynamically generate, and store to the storage, the shared IMSI and the shared secret key; the provisioning profile in the card, including the shared IMSI and the shared secret key, having been assigned to a plurality of other cards to enable other cellular devices comprising the respective cards to complete an authentication procedure via the cellular network with the MNO apparatus using the same shared IMSI and the same shared secret key, wherein the authentication procedure is compliant with a standard cellular communication protocol; a radio configured to connect to cellular networks; and the storage storing additional instructions that, when the cellular device is operating, are executed by the processor to cause the processor to use the shared IMSI and the shared secret key to perform the authentication procedure with the MNO apparatus to establish a channel, via the radio, with the cellular network; wherein the storage stores a master key, wherein the master key is stored by the other cellular devices, and wherein when the processor dynamically generates the shared IMSI and the shared secret key, the master key is used to generate the shared IMSI and the shared secret key; wherein the instructions to cause the processor to dynamically generate the shared IMSI and the shared secret key, and to perform the authentication procedure with the MNO apparatus comprise selecting the shared IMSI from a predetermined range; dynamically computing the shared secret key as a function of the shared IMSI and the master key; using the dynamically generated shared secret key and the selected shared IMSI to authenticate with the MNO; selecting, if there is a collision due to the selected shared IMSI being in use, another shared IMSI and repeating the selecting, computing, and using steps; and using the established channel on the MNO's network to provision the cellular device with a subscriber profile.