Confirm what server you are communicating with
A server certificate verifies the organization's identity to the client so that the client can securely browse the organization's Web site confident that:
- the website belongs to said organization (not an imposter), and
- transactions between the server and client are encrypted.
(
http://its.virginia.edu/identity/certificate/server/)因此我觉得答certificate没错
Prevent man-in-the-middle 觉得可能也是certificate, man-in-the-middle就是伪造public key,使发消息的一方误以为收到的public key是对方的(其实是man-in-the-middle),所以ppk肯定不对,certificate可以验证身份
Only confirm no change in identites compared to previous communication 这个觉得ppk没错
Make a brute force.... Salt没错
Requires a 3rd party service to be available 觉得self-signed certificate也没错
Protects against DDOS attack这个觉得几个答案好像都不太对,维基百科上说Approaches to DDoS attacks against cloud-based applications may be based on an application layer analysis, indicating whether incoming bulk traffic is legitimate and thus triggering elasticity decisions without the economical implications of a DDoS attack.
Has the most impact on total bandwidth of a server
这个不太确定,查了下,说certificate没影响多少带宽,salt无非使md5值长一点,这就影响带宽了?不确定
Most commonly abused这个不确定是self-signed 还是MD5,我更倾向于md5
对计算机安全这块只有些书本知识,不太熟,仅供参考