This blog will explore on the feasibility of flexibly using STM-1/4 optical module on OSN 500 optical interface.

According to Huawei's technical specifications, OptiX OSN 500 is a 1U, case-shaped SDH equipment that provides three slots, as shown in Table 1.

Table 1 OSN 500 Slot layout

The ISU slot houses a functional board integrating the SCC unit, cross-connect unit, clock unit, tributary unit, line unit, and data transparent transmission unit as shown Table 2.

Table 2 ISU boards supported by the OptiX OSN 500.

Based on the information in Table 2, it shows that the ISU board of the OptiX OSN 500 is integrated with 2-port STM-1/4 optical interfaces. We can reasonably assume that STM-1 or STM-4 modules can be randomly plugged into these two optical interfaces without encountering any limitations or alarms.

By making a module replacement test on OSN500, we obtained the answer to this question.

Test 1 On OSN 500 S4.1(SL4D) chassis

When we replace original STM-4 with STM-1 module then plugged into optical interface, a major alarm “LASER_MOD_ERR_EX” pops up below:

Test 2 On OSN 500 S1.1(SL1D) chassis

When we replace original STM-1 with STM-4 module then plugged into optical interface, a critical alarm “LSR_NO_FITED” pops up below:

LSR_NO_FITED: the pluggable optical module is not installed on the board. As a result, the board cannot receive and transmit services, and thus the board fails to function. After we replace it with STM-1 optical module, alarm disappears.

From above test, it proves that even ISU can support 2-port STM-1/4 optical interfaces, which does not mean we can randomly plug STM-1/4 optical module on OSN 500 interface. Thus, when you have OSN 500 project inquiry, it’s suggested to specify OSN 500 interface type either STM-4 or STM-1 you need, then we can help you equip the matched optical module type to avoid alarm or any potential issue to delay your deployment plan.

XPONSHOP can supply Huawei OSN 500 hardware and technical guide. If you have any related technical questions or project inquiry, please email us at sales@xponshop.com.