A problem in converting S3ORAM from 7 servers into 3 servers

[comeonsunny]

##The following is the modifications in config.h:

//=== SECRET SHARING PARAMETER================================================
#define NUM_SERVERS 3
#define PRIVACY_LEVEL 3
const long long int vandermonde[NUM_SERVERS] = {3 , -3 + P, 1};
//SERVER IP ADDRESSES
const std::string SERVER_ADDR[NUM_SERVERS] = {"tcp://localhost", "tcp://localhost", "tcp://localhost"};

##The compiling process has succeed. Then I just meet the next problem.

The problem happes in the access process

[thanghoang]

Hi, you should change PRIVACY_LEVEL to 1 for 3 servers case

[comeonsunny]

Thanks for your quick response.
From my perspective, I just consider the reason changing PRIVACY_LEVEL to 1 for 3 servers case is depended by folllowing equations.

which means in this case the client needs at least 2 shares to decrypt the key. Therefore, if the PRIVACY_LEVEL is set to 2, the client needs at least 4 shares to decrypt the key. However, there are only 3 server to provide shares. The results is the decrypting process will be cut down.
But there is another question. TO make it clear, you could see the following picture firstly.

IN my limited knowledge world, I think that you have used the SMP protocol in your code. With above condition has been achieved, if I just set PRIVACY_LEVEL to 3 for 3 servers, the result should be reasonable. Becase the client just need 3 shares to decrypt the key.