Huawei SSN4SLQ16 optical interface board function, hardware version N1, N2 and N4, N2SLQ16 single board has been discontinued. It supports functions and features such as receiving and transmitting 4-channel STM-16 optical signals, overhead processing, and multiplexed segment protection. Optical interface specifications: CWDM and DWDM color optical interfaces, single-fiber bidirectional optical modules. When the AU-3 service and TCM function are not used, the N1SLQ16 single board and N2SLQ16 single board can replace each other.The N4SLQ16 single board supports the single board compatible replacement function to replace the N1SLQ16/N2SLQ16.When configuring the multiplexing segment protection and SNCP, if the working board is the N2SLQ16 with the TCM function turned on or configured for the AU-3 service, the The protection board is not allowed to be N1SLQ16 that does not support TCM function and AU-3 service, otherwise the inversion will cause service interruption. Supports multiplexed segment shared optical path protection. Provides 8 sets of Kbyte processing capacity, and single optical port provides 2 sets of Kbyte processing capacity, and 1 SLQ16 board supports up to 8 MSP rings.N4SLQ16 supports VC-4 channel inner loopback and outer loopback functions. Inserted in slots 1 to 4 and slots 15 to 16, each single board can be configured with two optical ports. Inserted in slot 5 to slot 8, slot 11 to slot 14, each single board can be configured with 4 optical ports.