Hello everyone!
This post will share with you about the L1 service encryption system.
The L1 service encryption system consists of the OSN equipment with encryption boards, security management tools (for example, SMT), and network management systems (for example, U2000).
The signals transmitted by the OSN equipment use the Optical Transport Network (OTN) frame structure specified in ITU-T Recommendation G.709/Y.1331. The OSN equipment in the encryption system adds an encryption algorithm to signal processing to encrypt the OPUk payload (excluding the overhead and FEC area). In this way, the customer data is encrypted. The security management information that the encryption function uses is transmitted using OPUk overheads, without affecting client services.
Frame structure after client signal encapsulation:
As shown in the figure, client-side signals are mapped to the payload area in an OPUk frame, and then OPUk overheads are added to form a lower-order ODUk frame. Then, multiple ODUk frames are multiplexed into a higher-order ODUj (j = k + 1 or higher) frame, and then OTU overheads are added to form the final signal transmitted over an optical fiber.
Thank you!
