Convert the 32-bit binary IPv4 address 11001010.11110101.10000011.11101011 to dotted-hexadecimal notation.

Introduction / Context:
Network engineers sometimes represent IPv4 addresses in hexadecimal form, especially in low-level debugging or when working with certain protocols and configuration tools. Converting between binary and hexadecimal is faster and more compact than working only with binary, but it still accurately represents the same underlying bits.

Given Data / Assumptions:

• Binary IPv4 address: 11001010.11110101.10000011.11101011.
• Each dotted group is an 8-bit octet.
• Each octet will be converted to hexadecimal.
• Two hexadecimal digits represent one 8-bit binary value.

Concept / Approach:
To convert from binary to hexadecimal, group the bits of each octet into two groups of four bits (nibbles). Each nibble corresponds directly to one hexadecimal digit using the mapping 0000 to 0 through 1111 to F. Once each octet is converted into two hexadecimal digits, we join the four hexadecimal octets with dots to form dotted-hexadecimal notation. This preserves the structure of the original IPv4 address while shortening the representation.

Step-by-Step Solution:
1. First octet: 11001010 splits into 1100 and 1010. 1100 is C, 1010 is A, so the first octet is CA.2. Second octet: 11110101 splits into 1111 and 0101. 1111 is F, 0101 is 5, so the second octet is F5.3. Third octet: 10000011 splits into 1000 and 0011. 1000 is 8, 0011 is 3, so the third octet is 83.4. Fourth octet: 11101011 splits into 1110 and 1011. 1110 is E, 1011 is B, so the fourth octet is EB.5. Combine the hexadecimal octets: CA.F5.83.EB.

Verification / Alternative check:
As an additional check, you can convert each hexadecimal octet back to decimal via binary. For example, CA is 11001010 in binary, which is 202 in decimal. Performing this reverse conversion for all octets will confirm that the original binary sequence and the hexadecimal representation are equivalent.

Why Other Options Are Wrong:
Option B changes the first octet from CA to C9, which corresponds to different high-order bits. Option C uses F4 instead of F5 in the second octet, altering four bits. Option D changes the final octet from EB to EE, which again modifies the underlying binary bits. Any such change means the hexadecimal does not match the original binary address.

Common Pitfalls:
Typical errors include grouping bits incorrectly, forgetting that four bits equal one hexadecimal digit, or misreading binary values when referencing the hexadecimal conversion table. Another pitfall is accidentally converting the dotted-decimal representation instead of the provided binary, leading to a completely different result.

Final Answer:
CA.F5.83.EB