An image forming apparatus, comprising: a first interface unit, which includes a first port and a second port, respectively for establishing a first channel and a second channel between the image forming apparatus and a driving device in communication with the image forming apparatus; characterized by: an imaging controller, for receiving data from the first channel as page data to be imaged, and acquiring data from the second channel as virtual data that has been generated in accordance with a pre-established rule; and a timer, for calculating a first duration from a last time when the image forming apparatus receives either page data from the first channel or virtual data from the second channel, whichever comes later; wherein when the first duration reaches a first predetermined duration, the imaging controller performs timeout handling for ceasing a present imaging job; wherein the image controller is further configured to: acquire data from the second channel; judge whether the data acquired from the second channel conform to the pre-established rule; and determe the data acquired to be virtual data, if the data are judged to conform to the pre-established rule; wherein the pre-established rule prescribes that the data acquired comprise A, B, C, or D, or alternatively comprise D and any one of A, B, and C, among which: A represents any one of a pre-established group of data, or a pre-established datum; B represents data generated in accordance with a pre-established random number generation rule; C represents pre-established attribute information of an imaging job, including at least one selected from a group consisting of name, type of document, creator, sequence of current page data, size and creation time of the current page data of the imaging job; and D represents encrypted data obtained by encrypting above A, B, or C with a specified key. an imaging controller, for receiving data from the first channel as page data to be imaged, and acquiring data from the second channel as virtual data that has been generated in accordance with a pre-established rule; and a timer, for calculating a first duration from a last time when the image forming apparatus receives either page data from the first channel or virtual data from the second channel, whichever comes later; wherein when the first duration reaches a first predetermined duration, the imaging controller performs timeout handling for ceasing a present imaging job; wherein the image controller is further configured to: acquire data from the second channel; judge whether the data acquired from the second channel conform to the pre-established rule; and determe the data acquired to be virtual data, if the data are judged to conform to the pre-established rule; wherein the pre-established rule prescribes that the data acquired comprise A, B, C, or D, or alternatively comprise D and any one of A, B, and C, among which: A represents any one of a pre-established group of data, or a pre-established datum; B represents data generated in accordance with a pre-established random number generation rule; C represents pre-established attribute information of an imaging job, including at least one selected from a group consisting of name, type of document, creator, sequence of current page data, size and creation time of the current page data of the imaging job; and D represents encrypted data obtained by encrypting above A, B, or C with a specified key. acquire data from the second channel; judge whether the data acquired from the second channel conform to the pre-established rule; and determe the data acquired to be virtual data, if the data are judged to conform to the pre-established rule; wherein the pre-established rule prescribes that the data acquired comprise A, B, C, or D, or alternatively comprise D and any one of A, B, and C, among which: A represents any one of a pre-established group of data, or a pre-established datum; B represents data generated in accordance with a pre-established random number generation rule; C represents pre-established attribute information of an imaging job, including at least one selected from a group consisting of name, type of document, creator, sequence of current page data, size and creation time of the current page data of the imaging job; and D represents encrypted data obtained by encrypting above A, B, or C with a specified key. A represents any one of a pre-established group of data, or a pre-established datum; B represents data generated in accordance with a pre-established random number generation rule; C represents pre-established attribute information of an imaging job, including at least one selected from a group consisting of name, type of document, creator, sequence of current page data, size and creation time of the current page data of the imaging job; and D represents encrypted data obtained by encrypting above A, B, or C with a specified key.