How to verify the value from a member in one group?

[streetycat]

At least, we need the infomations below:

1. The block that generated the root state mount on the GroupState tree;
2. The signatures from 2/3 admins for the block, It can avoid some malicious nodes provide the wrong value;
3. The tree nodes in all the path for the GroupState tree, It is difficult to describe，Examples are as follows:

// The RPath folders
|--root
    |--folder1
    |--folder2
        |--folder2-1
        |--folder2-2

If I want get the object mount at "/root/folder2/folder2-1", I must get the ObjectMaps below:
* "root", we can get the ObjectId eq with the result-state in the block, and we can get the keypair <folder2, value> in next branch from the "root" ObjectMap;
* "/root/folder2", we can get the ObjectId eq with the keypair <folder2, value> from "root", and we can get the keypair <folder2-1, value> in next branch from the "folder2" ObjectMap;
* "/root/folder2/folder2-1", the target object we need, We can get the ObjectId eq with the keypair <folder2-1, value> from "folder2"

So. We need the total ObjectMap infomation of each branch, and the target Object.

In most cases, It will workable, but it'll be inefficient when there are too many branchs, because of the large redundance information.

Maybe we need other solution for large data volume scenario:

Each admins make a signature on every value on the branchs on-demand:

1. vote to the value when someone request it
2. and cache it for next request

The client can verify it only with the signatures from 2/3 admins, without the ObjectMaps of the branchs.