Goldman Sachs: Optical Networking

> Driven by an AI infrastructure ramp-up and rising computing power per rack, Goldman Sachs forecasts a 9x expansion in the total addressable market (TAM) from US$15bn (GB300 NVL72, mainly in 2026) to US$154bn (Rubin Ultra NVL576, mainly in 2028).

> CPO is projected to contribute US$91bn, capturing 59% of the overall US$154bn TAM (assuming a 29% penetration rate in scale-out).

> Aggregate networking dollar content per computing unit across scale-up and scale-out is expected to surge 29x, jumping from US$315k in the GB300 NVL72 to US$9.4bn in the Rubin Ultra NVL576. Per computing unit, dollar content increases by 16x in Scale-Out and 45x in Scale-Up.

> The addressable market for optical modules/engines expands 13x when moving from scale-out to scale-up architectures.

Pluggable Optical Modules & Silicon Photonics (SiPh)

> The value market for pluggable optical modules in scale-out will grow 10x per computing unit from the 2H25 server model to the 2H27 server model.

> Equivalent 1.6T units per computing unit will skyrocket from 216 units (GB300 NVL72) to 2.5k units (Rubin Ultra NVL576).

> Silicon Photonics adoption in the datacom market is expected to spike from 6% in 1Q24 to 45% by 4Q28, offering up to a 32% BoM cost advantage and 20% price advantage over traditional EML solutions at 1.6T speeds.

Technology Matrix & Supply Chain Realities

> Copper cables and PCBs remain king for short-distance, cost-effective, and low-power connections, but optics become essential for high-speed, long-distance interconnections.

> Light source supply (both EML and CW lasers) is expected to remain very tight through 2026/2027 due to booming AI demand and Indium Phosphide (InP) substrate export controls from China. Supply balance isn't expected until 2H28 as supply chain expansions come online.

> Alternative entirely optical signal switches (like Google's Palomar OCS) are scaling rapidly, enabling datacenter speed upgrades without needing to replace the switches themselves. Lumentum’s OCS backlog crossed $400M as of Feb 2026.

This is a report from April which is made publicly online by GS, but I don't think people covered it enough. Hence, revisiting and highlighting key data potentially missed.