544
kshell
TCP · 0x0220
Port 544 — kshell
Authentication
Port 544 carries Kerberos remote shell over TCP. Being at or below 1023, only root may open it on Unix.
0–1023. On Unix only root may open one.
Where it sits in 65535
A port number is 16 bits, so it stops at 65535. The narrow band at the left is everything up to 1023.
065535
- Service
- Kerberos remote shell (kshell)
- Kind
- Authentication
- Protocol
- TCP
- Range
- Well-known
- Root needed
- Yes
- Hexadecimal
- 0x0220
- Binary
- 0000001000100000
- Two bytes
- 2 · 32
Same kind
Checking who you are and handing out keys.
Ports next to it
How to read this
- A port number is 16 bits, so it runs 0 to 65535. There is no port 65536.
- Opening anything at or below 1023 needs root on Unix.
- Plain and encrypted often live on different numbers — 80 and 443, for one.
- Numbers like 3000 and 8080 were never registered; those are marked as custom.
Frequently asked questions
Q. What is port 544 used for?
Kerberos remote shell (kshell) uses it, over TCP.
Q. Does opening port 544 need root?
Yes. It is at or below 1023, so on Unix only root may open it.
Q. Which range does port 544 fall in?
Well-known (0–1023). In hex it is 0x0220.
Q. Does port 544 have a twin?
Not a separate one. It either was encrypted from the start or negotiates TLS on the same number.