Nvidia: The Rival That Arrives With the GPUsThin moat

Cisco Systems (CSCO) — moat facet

Nvidia's Ethernet revenue grew 2.8 times in a quarter because it sells the network to buyers who already have to buy its GPUs.

Nvidia competes with Cisco from a position no networking company can match: it sells the GPUs the customer is building the data centre around. Cisco names Nvidia among its competitors1, and IDC put Nvidia first in data-centre Ethernet switching in the first quarter of 2026 with 21.5%2.

Ethernet revenue, Q2 2026 ($bn)5.43 (+36.2%)Cisco, all Ethernet3.86 (2.8x)NvidiaThe Next Platform on IDC Q2 2026 Ethernet data
Cisco is larger; Nvidia is growing far faster.

The speed is the point. In the second quarter of 2026 Cisco's total Ethernet revenue grew 36.2% to $5.43 billion, "but Nvidia grew by 2.8X", to $3.86 billion3. Arista's pages in this collection chart how quickly Nvidia rose in data-centre Ethernet.

The relationship is harder for Cisco than a normal rivalry because Nvidia does not have to win on the switch alone. A buyer who needs Nvidia's GPUs is already negotiating with Nvidia, and the network can be added to the same order.

Cisco's defence is to sell to buyers who want a network independent of their GPU supplier, and its hyperscaler orders show such buyers exist: $9.3 billion in fiscal 20264.

IDC's first-quarter report was headlined by Nvidia becoming number one in data-centre Ethernet switching as the market surged 39.8% to $15.4 billion5. A market growing that fast has room for several winners, which is why Cisco's own data-centre revenue rose 43.0% in the same quarter6 while it lost share.

What tells the story is Cisco's total Ethernet revenue against Nvidia's. Cisco is still larger overall, $5.43 billion to $3.86 billion in the second quarter7; if Nvidia passes it within a year, the GPU vendor will have become the default network vendor as well.

Moat trajectory: Narrowing

Nvidia first in DC Ethernet; grew 2.8x in Q2 2026.

The number that tests this moat
Third-party estimate
Ethernet revenue vs Nvidia, latest quarter
Cisco $5.43bn (+36.2%) vs Nvidia $3.86bn (2.8x) (Q2 2026)

Whether the GPU vendor becomes the default network vendor; Nvidia passing Cisco overall would confirm it.

Source: The Next Platform on IDC Q2 2026 Ethernet ↗
References
  1. ReportedCisco names Nvidia among its competitors, and IDC put Nvidia first in data-centre Ethernet switching in the first quarter of 2026 with 21.5%.
    Cisco Systems Form 10-K for fiscal 2026 (year ended 25 July 2026) - Item 1A risk factors, competition and legal proceedings. — FY2026 · publ. 2 September 2026 · source ↗
  2. Third-party estimateCisco names Nvidia among its competitors, and IDC put Nvidia first in data-centre Ethernet switching in the first quarter of 2026 with 21.5%.
    DataCenterKnowledge on IDC 1Q26 - data-centre Ethernet switching shares: Nvidia 21.5%, Arista 20.7%, Cisco 17.8%. — 1Q26 · publ. 2026 · source ↗
  3. Third-party estimateIn the second quarter of 2026 Cisco's total Ethernet revenue grew 36.2% to $5.43 billion, "but Nvidia grew by 2.8X", to $3.86 billion.
    The Next Platform on IDC's Q2 2026 Ethernet data - Cisco Ethernet $5.43bn (+36.2%), data-centre $2.24bn (+77.3%), Arista $2.3bn, Nvidia $3.86bn. — Q2 2026 · publ. 20 September 2026 · source ↗
  4. ReportedCisco's defence is to sell to buyers who want a network independent of their GPU supplier, and its hyperscaler orders show such buyers exist: $9.3 billion in fiscal 2026.
    Cisco fourth-quarter and fiscal 2026 results release, Form 8-K exhibit 99.1 - quarterly revenue by line and segment, margins, AI infrastructure orders and fiscal 2027 guidance - orders, acquisitions, dividend and fiscal 2027 guidance. — Q4 FY2026 · publ. 12 August 2026 · source ↗
  5. Third-party estimateIDC's first-quarter report was headlined by Nvidia becoming number one in data-centre Ethernet switching as the market surged 39.8% to $15.4 billion.
    IDC, Worldwide Ethernet switch and router tracker, 1Q26 - Cisco switching revenue $4.5B and 29.3% share, router share 35.1%. — 1Q26 · publ. 2026 · source ↗
  6. Third-party estimateA market growing that fast has room for several winners, which is why Cisco's own data-centre revenue rose 43.0% in the same quarter while it lost share.
    IDC, Worldwide Ethernet switch and router tracker, 1Q26 - Cisco switching revenue $4.5B and 29.3% share, router share 35.1%. — 1Q26 · publ. 2026 · source ↗
  7. Third-party estimateCisco is still larger overall, $5.43 billion to $3.86 billion in the second quarter; if Nvidia passes it within a year, the GPU vendor will have become the default network vendor as well.
    The Next Platform on IDC's Q2 2026 Ethernet data - Cisco Ethernet $5.43bn (+36.2%), data-centre $2.24bn (+77.3%), Arista $2.3bn, Nvidia $3.86bn. — Q2 2026 · publ. 20 September 2026 · source ↗
Sources
Generated September 25, 2026