Vega for Constant Maturity Swaps

Why does a Constant Maturity Swap have a positive vega? Is it because of the convexity? How does one hedge it?

• (1) Yes. Intuitvely, the convexity correction is a function of $\sigma^2$ and therefore the pricing of CMS swap depends on volatility. (2) With Swaptions. – Alex C Jul 2 at 14:51