The first way to improve the scalability of a blockchain network is not to touch the architecture explained in Introduction - Why Scaling Matters, but to add a combination of hardware and software optimizations to scale the system. Solana is perhaps the best example of such an approach. This method evidently works to an extent, as seen in the high transaction rates of Solana, but it also poses some challenges:
- The hardware requirements to run a validator are increasingly high.
- At the end of the day, this method is a form of vertical scaling, and there are questions about whether it will grow indefinitely or not.
All of the properties of vertical scaling discussed in Vertical and Horizontal Scaling apply to this approach.