How many possible sequence number combinations are there in TCP/IP protocol?

How many possible sequence number combinations are there in TCP/IP protocol?

• A. 320 billion
• B. 32 million
• C. 4 billion
• D. 1 billion

Answer: (C)

TCP assigns sequence numbers using a 32-bit field for the byte position in the data stream. Because the field is 32 bits wide, it can represent 2^32 distinct values, which is a very large finite space—commonly described as a bit over four billion. That wide range ensures each byte in the connection can be uniquely identified, and sequence numbers wrap around only after reaching that maximum value. For practical purposes, this is described as about four billion possible sequence numbers, making the stated answer the closest and most accurate option.

TCP assigns sequence numbers using a 32-bit field for the byte position in the data stream. Because the field is 32 bits wide, it can represent 2^32 distinct values, which is a very large finite space—commonly described as a bit over four billion. That wide range ensures each byte in the connection can be uniquely identified, and sequence numbers wrap around only after reaching that maximum value. For practical purposes, this is described as about four billion possible sequence numbers, making the stated answer the closest and most accurate option.