1, mature technology. Digital signature is a mature technology, widely used in e-commerce and e-government. It takes a long time and a short time for the firewall, so the digital signature technology is relatively mature.

2. High integrity. Digital signature can verify whether the original document has been changed during transmission, and ensure the integrity, authenticity and non-repudiation of the transmitted electronic document, while the firewall cannot guarantee the integrity and authenticity of transmission, so digital signature has high integrity.