563
nntps
TCP · 0x0233
Port 563 — nntps
Messaging
Port 563 carries Usenet news over TLS 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
- Usenet news over TLS (nntps)
- Kind
- Messaging
- Protocol
- TCP
- Range
- Well-known
- Root needed
- Yes
- Hexadecimal
- 0x0233
- Binary
- 0000001000110011
- Two bytes
- 2 · 51
- Plain twin
- 119
Same kind
Passing messages along, or queueing them up.
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 563 used for?
Usenet news over TLS (nntps) uses it, over TCP.
Q. Does opening port 563 need root?
Yes. It is at or below 1023, so on Unix only root may open it.
Q. Which range does port 563 fall in?
Well-known (0–1023). In hex it is 0x0233.
Q. What does port 563 wrap?
It is port 119 wrapped in TLS.