This document discusses securing TCP/IP networks. It covers four main areas of TCP/IP security: encryption, non-repudiation, authentication, and authorization. Encryption involves scrambling data so it can only be unscrambled by the intended recipient. Common encryption standards discussed include asymmetric key algorithms which allow secure key exchange. Secure TCP/IP applications then use these standards and tools to protect data in transit, such as HTTPS which uses SSL/TLS encryption for web traffic security.

1. CompTIA Network+
in a Nutshell
Chapter Eleven

2. Objectives
• Discuss the standard methods for securing
TCP/IP networks
• Compare TCP/IP security standards
• Implement secure TCP/IP applications

3. TCP/IP and Security
The “inventors” of TCP/IP did not include
any real security

4. • User names and passwords on FTP, Telnet,
etc. do not begin to protect TCP/IP
applications
• Today every device with a public IP address on
the Internet is targeted
• Data moving between two hosts is
intercepted and read
• TCP/IP in its original form does not stop the
bad guys

5. • Making TCP/IP Secure
• The four areas of securing TCP/IP
A. Encryption -To scramble, mix up, change data
It can be unscrambled by the person receiving
it
B. Non-repudiation - Process that guarantees
that the data is as originally sent and came
from the source you think it came from

6. C. Authentication -Verifying that whoever
accesses the data is the person you want
accessing the data/ Classic form: user name
and password combination
D. Authorization- Defines what a person
accessing the data can do with it
Example: Windows permissions assigned to a
user account

7. • Encryption
A. Plaintext and Cleartext
-Two names for same thing
Data in easily read or viewed industry-wide
standard format
-Does not mean that it is just “text”

8. B. Cipher
-series of complex and hard-to-reverse
mathematics (an algorithm)
-You run the cipher on a string of ones and
zeroes to make a new set of ones and zeroes

9. • Asymmetric-Key Algorithm Standards
- Serious drawback to symmetric-key
algorithms
- Anyone who has the key can encrypt or
decrypt data
- Forces us to somehow send the key to the
other person
• Asymmetric-key algorithms developed as a
method for the encryptor to safely send a key
to the decryptor

10. • Secure TCP/IP Applications
A. The applications that use the above standards
and tools
B. HTTPS [Introduced in Chapter 9]
- HTTPS documents page addresses begin with
https://
-Most browsers also show a lock icon
somewhere
- HTTPS uses SSL/TLS for