Arista Warrior, 2nd Edition

Chapter 4. Merchant Silicon

If you’ve shopped for data center switches with any of the major networking equipment vendors recently, you’ve likely heard the term merchant silicon thrown around. When I wrote the first edition of this book, there was a lot of back and forth between the major players about custom silicon versus merchant silicon, and which one is better. Although many of the big players have adopted the ways of merchant silicon, there are still times when vendors will try to convince a potential customer that the Arista way is the wrong way. Let’s take a look at the details and see whether one really is better than the other.

The Debate

To begin, let’s define our terms:

Custom silicon

Custom silicon is a term used to describe chips, usually Application Specific Integrated Circuits (ASICs), that are custom designed and usually built by the company selling the switches in which they are used. Another term I might use would be in house when describing such chips. As an example, Cisco Nexus 7000 switches use Cisco-designed proprietary ASICs.

Merchant silicon

Merchant silicon is a term used to describe chips, usually ASICs, that are designed and made by an entity other than the company selling the switches in which they are used. I might be tempted to say such switches use off-the-shelf ASICs, though that might imply that I could buy these chips from a retail store. I’ve looked, and Walmart doesn’t carry them. As an example, Arista’s 7280R switches use Broadcom’s Jericho ...