chapter339, [SORA] draft: renewal Whitepaper 1, introduction

1, introduction

Welcome to SORA Network!
First, we would talk a concept in SORA Network.
SORA ネットワークにお付き合いいただき、誠にありがとうございます。

1-A, About sufficient and necessary conditions for drive scan
1-A, ドライブ検査に対する十分条件ならびに必要条件について

  • Regarding HDD/SSD/NVMe, Let’s consider the logic from α to β below.

α: Confirmation of normality by full scan.
β: There is no problem sequential and random read/write.
α: 完全な検査(完全スキャン)で正常性を確認
β: シーケンシャルおよびランダムの読み書きは問題ありません

  • First, scanning of HDD come to necessary and sufficient condition. Therefore, in the case of HDD, the old scan logic is no problem. Simply, just check the good or bad of a sectors.
  • Next is the case of SSD/NVMe, necessary conditions is OK, but not sufficient conditions. Therefore, must be not only check the quality of a sectors but also a drive benchmark and so on used as other mapping.

1-B, Why is this result?
1-B, どうしてそのような結果に?

  • The reason is that the correspondence from state of sectors to scan results is that HDD is bijection, but SSD/NVMe is monomorphism.
  • In other words, even if you perform a sector scan on SSD/MVMe, they does not mean that they have been checked all target in flash memory due to monomorphism. Therefore, the sufficient conditions are not satisfied.

1-C, So what should?
1-C, では、どうするべきか?

  • First of all, “data protection” is the highest priority for drive scan. Because this aim to scan that are carried out to protect the data.
    まず第一に、「データ保護」はドライブスキャンの最優先事項です。 これは、データを保護するために実行されるスキャンを目的としているためです。
  • If you won’t need to protect data, there is one easy way to make a bijection with SSD/NVMe. That is to write “random numbers” to all sectors, in this case, sectors prediction management is not possible, so bijection is used.
  • However, that doesn’t make sense.
    We need logic to determine when to replace a drive while preserving the data.
  • Therefore, we have adopted a mechanism that collects statistical elements in drive status by the Blockchain and sandwiches a mapping that converts monomorphism to surjection, as if it see object from inner to outer by a lens.
    Building that Blockchain … is one of the purposes of SORA Network.