11. A communication system comprising: a handheld telecommunications device; a main database system; a first network connection configured to exchange data between the main database system and a local database system, the local database system being configured to connect to the main database system via the first network connection, the main database system and the local database system being separated by a first firewall; a digital mobile telecommunication connection between the handheld telecommunications device and the local database system, the local database system being configured to connect to the handheld telecommunications device via the digital mobile telecommunication connection, the local database system and the handheld telecommunications device being separated by a second firewall, the digital mobile telecommunication connection tunneling through the second firewall; and the local database system including a memory configured to store machine executable instructions, and at least one processor configured to execute the machine executable instructions to create a local database instance, receive user permissions from the main database system through a database tunnel implemented using the first network connection, the database tunnel tunneling through the first firewall, receive a portion of a document database via the database tunnel, the document database corresponding to a document, receive a request for a user document from the handheld telecommunications device via the digital mobile telecommunication connection, map the portion into the user document, send the user document to the handheld telecommunications device via the digital mobile telecommunication connection, receive a modified document from the handheld telecommunications device via the digital mobile telecommunication connection, the modified document including a modification request specifying a modification of the portion, extract the modification request from the modified document, forward the modification request to the main database system via the database tunnel only if the modification request is allowed by the user permissions, and synchronize the local database instance with the document database through the database tunnel.
11. A communication system comprising: a handheld telecommunications device; a main database system; a first network connection configured to exchange data between the main database system and a local database system, the local database system being configured to connect to the main database system via the first network connection, the main database system and the local database system being separated by a first firewall; a digital mobile telecommunication connection between the handheld telecommunications device and the local database system, the local database system being configured to connect to the handheld telecommunications device via the digital mobile telecommunication connection, the local database system and the handheld telecommunications device being separated by a second firewall, the digital mobile telecommunication connection tunneling through the second firewall; and the local database system including a memory configured to store machine executable instructions, and at least one processor configured to execute the machine executable instructions to create a local database instance, receive user permissions from the main database system through a database tunnel implemented using the first network connection, the database tunnel tunneling through the first firewall, receive a portion of a document database via the database tunnel, the document database corresponding to a document, receive a request for a user document from the handheld telecommunications device via the digital mobile telecommunication connection, map the portion into the user document, send the user document to the handheld telecommunications device via the digital mobile telecommunication connection, receive a modified document from the handheld telecommunications device via the digital mobile telecommunication connection, the modified document including a modification request specifying a modification of the portion, extract the modification request from the modified document, forward the modification request to the main database system via the database tunnel only if the modification request is allowed by the user permissions, and synchronize the local database instance with the document database through the database tunnel. 12. The communication system of claim 11 , wherein the extraction of the modification request includes comparing the user document to the modified document.