September 2018
Beginner to intermediate
224 pages
5h 33m
Japanese
Content preview from 図解まるわかり セキュリティのしくみ
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
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公開鍵暗号には、公開された鍵が正しい相手の鍵である保証がないとい
う不安があります。AさんがBさんになりすまして、Bさんの公開鍵を公
開しても、それが正しいかを判断できません。公開鍵と秘密鍵を作成する
のは自由なので、Bさんになりすますことが可能なのです。
実社会でも、他人になりすまして印鑑を作成されると、その印鑑が本人
のものか判断できません。ただし印鑑の場合は、公的機関に印鑑登録して
おけば、印鑑証明書によって本人のものであることを確認できます。
公開鍵暗号も同様で、公開鍵を管理する認証機関によって「間違いない
相手である」という証明書が発行されると、安心して取引を行うことがで
きます。この機関を（CertificateAuthority：）と呼び、こうし
た認証の基盤になっているのが（PublicKeyInfrastructure：
）です（図5-8）。
認証局は誰でも作れるので、攻撃者が勝手に作成した認証局では信頼で
きません。そこで、信頼できる認証局によって発行された証明書であるこ
とを検証するためにが使われます。
証明書チェーンはとも呼ばれ、その証明書を発行した認証局を
順にたどって、信頼できる認証局までたどれるかどうかを調べるために使
われます。図5-9のように、発行された証明書に含まれる認証局のデジタ
ル署名を順に確認し、最上位の認証局に到達できるか確認します。
この最上位にあたる証明書をと呼びます。Webサイトを閲 ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.