Internet History
This material mainly introduces the following parts:
- Some outstanding figures in the history of Internet development
- Several important stages in the history of the Internet
Phone Line Networking 电话网络
- Dial-Up Access 拨号访问
Data Transfer with Leased Lines 使用租用线路进行数据传输
Store and Forward Networking 存储和转发网络
- Typically specialized in Mail
E-Mail could make it across the country in six hours to about 2 days
then some valuable questions about research networks were raised during 1960-1980’s
came up with the following solution:
Efficient Message Transmission: Packet Switching 分组交换
- Challenge: in a simple approach, like store-and-forward, large messages block small ones
- Break each message into packets 消息拆分成包
- Can allow the packets from a single message to travel over different paths, dynamically adjusting for use 在不同路径上传输
Use special-purpose computers, called routers, for the traffic control
Shared Network 共享网络
- Supercomputers 超级计算机
- NSF Net 美国国家科学基金会资助的一个网络以使得研究人员能够共享他们的研究成果
CERN 欧洲核子研究组织
The Explosive Growth of the Web 网络的爆炸式增长
- Mosaic - Netscape - Mozilla - Firefox
- Netscape, JavaScript and FireFox
World-Wide-Web Consortium
Security
I learned briefly from this information：
- Some people will want to benefit from your information
"Perfect security" is unachievable
下面介绍了一些术语（Terminology）
- Confidentiality 保密
-- Prevent unauthorized viewing of private information - Integrity 完整性
-- Information is from who you think it is from and has not been modified since it was sent - Plaintext （明文） is a message that will be put into secret form.
- Ciphertext （密文） is a transformed version of plaintext that is unintelligible to anyone without the means to decrypt
- The transformation of plaintext to ciphertext is referred to as encryption（加密）.
- Returning the ciphertext back to plaintext is referred to as decryption（解密）.
The strength of a cryptosystem is determined by the encryption and decryption techniques and the length of the key. - Two basic types of cryptosystems exist, secret-key（秘钥）and public-key（公钥）.
- In a secret-key scheme, the key used for encryption must be the same key used for decryption. Also called symmetric-key cryptosystem.
Secret-key cryptosystems have the problem of secure key distribution to all parties using the cryptosystem.