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SSCP · Question #1150
SSCP Question #1150: Real Exam Question with Answer & Explanation
The correct answer is B: 65536. The total number of available TCP/UDP ports is 65536, ranging from 0 to 65535.
Submitted by helene.fr· Apr 18, 2026Network and Communications Security
Question
There are ______ available service ports
Options
- A65535
- B65536
- C1024
- D1-1024
- EUnlimited
Explanation
The total number of available TCP/UDP ports is 65536, ranging from 0 to 65535.
Common mistakes.
- A. 65535 represents the highest port number, but the count also includes port 0, making the total number 65536.
- C. 1024 refers to the count of well-known ports (0-1023), not the total number of available ports.
- D. 1-1024 specifies a range, not the total count, and it omits port 0 from the count of well-known ports.
- E. The number of available service ports is finite, determined by the 16-bit port number addressing scheme.
Concept tested. TCP/UDP port numbering
Reference. https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml
Topics
#Service Ports#TCP/UDP Ports#Networking Fundamentals
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