HMAC over MD5

NavyMooseCCNA

Good Morning Everyone,

I'm studying for my Security+ using Darril Gibson's book. Chapter 10 discusses Crypto and I'm not understanding HMAC and how it works over MD5. I re-read the section several times and found mainly fluff and not much meat. I'm having trouble understanding why you would do this instead of just using MD5. In my humble opinion, the HMAC sections are on the weak side and not explained very well.

If anyone can explain this to me, I would appreciate it.

Thank you in advance.

gespenstern

Read wiki article on HMAC, it has exact formula and pseudocode. From computational viewpoint (cracking) it is roughly twice more expensive than just a hashing algorithm used (like MD5).