According to the official Huawei hardware description for the OptiX RTN 950, the Indoor Unit (IDU) chassis has a height of 88 mm. The standard rack unit (U) is defined as 44.45 mm. Therefore, the height of the RTN 950 IDU in rack units is calculated as 88 mm / 44.45 mm, which is approximately 2U. This physical dimension is a standard specification for this equipment model.

A. 1U is 44.45 mm, which is half the actual height of the RTN 950 IDU.

C. 4U is 177.8 mm, which is double the actual height of the RTN 950 IDU.

D. 3U is 133.35 mm, which is significantly taller than the actual height of the RTN 950 IDU.

1. Huawei Technologies Co.

Ltd. (2019). OptiX RTN 950 Radio Transmission System V100R019C10 Hardware Description. Document Issue 13. Section 2.1 "IDU 950"

Table 2-1 "Technical specifications of the IDU 950"

Page 10. The document explicitly states the dimensions (H x W x D) as "88 mm x 442 mm x 220 mm".

2. Huawei Technologies Co.

Ltd. (2017). OptiX RTN 900 Radio Transmission System V100R009C00 Product Description. Document Issue 11. Section 4.3.1 "Mechanical Specifications"

Table 4-10 "Mechanical specifications". Page 51. This document

covering the broader RTN 900 series

also lists the dimensions for the OptiX RTN 950 chassis as 88 mm x 442 mm x 220 mm (2U).