协议速查表
| 协议 | 全称 | 功能 |
|---|
| HTTP | HyperText Transfer Protocol | 传输网页 |
| HTTPS | HTTP + SSL/TLS | 加密传输网页 |
| FTP | File Transfer Protocol | 文件上传/下载 |
| SMTP | Simple Mail Transfer Protocol | 发送邮件 |
| POP3 | Post Office Protocol v3 | 下载邮件到本地 |
| IMAP | Internet Message Access Protocol | 在服务器管理邮件 |
| BitTorrent | — | P2P 文件共享 |
TCP/IP 四层模型
| Layer | 功能 | 协议举例 |
|---|
| Application | 应用层协议 | HTTP, FTP, SMTP |
| Transport | 端到端传输 | TCP, UDP |
| Internet | 路由寻址 | IP |
| Link | 物理传输 | Ethernet |
Packet vs Circuit Switching 对比
| Circuit Switching | Packet Switching |
|---|
| Path | Dedicated | Shared |
| Delay | Low, constant | Variable |
| Bandwidth | Guaranteed | Best effort |
| Efficiency | Low (burst) | High |
| Fault tolerance | Low | High |
| 例子 | Phone network | Internet |
必考答题模板
Describe a protocol
[Protocol name] is used for [purpose]. It [key function].
Compare switching methods
Circuit switching establishes a dedicated path while packet switching splits data into packets. An advantage of circuit switching is guaranteed bandwidth, while a disadvantage is inefficiency for burst traffic.
Red Flags 🚩
- SMTP = Send Mail，不是 receive
- TCP/IP 是 四层 不是七层
- Router 看 IP 地址，不是 MAC 地址
- HTTPS 的 S 代表 SSL/TLS
- BitTorrent 是 P2P，不是 client-server
考试快速检查清单