topic 6

Data Notation in Networking

Overview

  • Discusses notation of data based on its type.

  • Three primary notations in the industry: Dotted Decimal Notation, Binary Notation, and Hexadecimal Notation.

Types of Notations

  1. **Dotted Decimal Notation (DDN)

    • Used primarily for IPv4 addresses and subnet masks.

    • Abbreviation: DDN.

    • Familiarity with DDN based on base 10 number system; starts at 0 and goes to 9.

    • Example: IPv4 address 172.20.0.24.

    • Represented as four octets, each containing 8 bits, leading to 32 bits total.

    • Conversion: DDN to Binary and vice versa.

    • Processes: Run IP config to find IPv4 address and subnet mask.

  2. Binary Notation

    • Base two number system consisting solely of 1s and 0s.

    • Example: 1 being "on" and 0 being "off".

    • Each column in binary corresponds to a power of 2:

      • Convert binary to DDN by totaling up the contributions of on bits:
        128,64,32,16,8,4,2,1128, 64, 32, 16, 8, 4, 2, 1

    • Conversion: Start counting bits and determining place value. See connections between octets (8-bits each).

  3. Hexadecimal Notation

    • Base 16 system, consisting of digits 0-9 and letters A-F (where A=10, B=11, C=12, D=13, E=14, F=15).

    • Commonly used for IPv6 addresses and MAC addresses.

    • IPv6: 128-bit, MAC: 48-bit.

    • Conversion: Split binary into nibbles (4-bit segments), convert each to hexadecimal.

    • Verbal explanation of methods for conversion.

Conversion Processes

From Dotted Decimal to Binary

  • Process involves subtracting the values from binary representation:

    • Example Conversion: Convert 172, 20, 0, 64 to Binary.

    • 172 can subtract from 128 to yield 44; repeat for other octets.

From Binary to Dotted Decimal

  • Count from the left side onward, adding the power values for each bit that is on (1).

  • Example with binary 10101100 to get DDN 172.

Practical Application of Notation

  • Importance of conversion in networking and subnetting.

  • Emphasizes why understanding binary, hexadecimal, and dotted decimal is crucial for networking tasks such as addressing and subnetting.

Value of Data

  • Discusses importance of data in IT and its protection.

  • Data is crucial for businesses and customers, emphasizing its monetary value.

    • Example: Change Healthcare ransomware incident impacting organizational integrity and financials.

    • Cost implications of data breaches, including lost revenue, reputation, and operational disruption.

Examples of Data Breaches

  • Incident mentioned involving Change Healthcare:

    • Attacked by Black Cat Group; $25 million ransom without data recovery.

    • Implications: Losses exceeded $3.2 billion overall due to damages, lost trust, and business continuity issues.

  • Importance of Multi-Factor Authentication (MFA) in protecting against breaches.

Measurement of Data

  • Discusses units of measure used:

  1. Bits and Bytes:

    • Smallest unit: bit (b), larger unit: byte (B).

    • 1 byte = 8 bits.

    • Throughput speed measured in bits per second (bps).

    • Storage measured in bytes (kilobytes, megabytes, gigabytes).

  2. Network vs. Storage Measurement:

    • Network speeds in bits (bps), and storage measurements in bytes (B).

Importance of Backups and Recovery

  • Best defense against ransomware attacks is maintaining backups.

  • Need to verify the integrity of backups to ensure data can be recovered.

  • Example of Toy Story 2: accidental deletion of data recovered due to lucky backup discovery.

Conclusion

  • Importance of understanding data notation, its value, measurements, and recovery techniques.

  • Emphasizes role of strong access control policies, least privilege principles, and being prepared for threats (internal, external, physical).