1, in the interest rate swap, there are reasons for the source of free cakes: ① the risk is small. Because the interest rate swap does not involve the principal, the two sides only exchange interest rates, and the risk is limited to the interest payable, so the risk is relatively small; ② The influence is slight. This is because the interest rate swap has no influence on the financial statements of both parties, and the current accounting standards do not require the interest rate swap to be listed in the notes to the statements, so it can be kept confidential; ③ Low cost. Through communication, both sides realized their wishes and reduced the financing cost; (4) Simple procedures and quick transactions. The disadvantage of interest rate swap is that there is no standardized contract like futures trading, and sometimes the other party of the swap may not be found. 2. In interest rate swap, there is the essence of free cake source: for a currency, both the holders of bottom line interest rate and floating interest rate are faced with the influence of interest rate changes. For debtors with fixed interest rates, if the interest rate trend rises, their debt burden is relatively high; For debtors with floating interest rates, if the interest rate trend rises, the cost will increase.