Ports

Only the services you switch on open a port. The Services screen in PBConfig shows and changes all of them. See The Services screen.

Service Port Protocol Notes
Telnet 23 TCP Always on. The in-browser terminal shares this listener.
SSH 22 TCP Off until you enable it. Stop Windows OpenSSH Server first if it owns port 22.
RLogin 513 TCP Optional.
Web (PBWeb) 80 TCP HTTP only for now.
FTP (PBFtp) 21 TCP Plus passive data ports 50100 to 50200.
NNTP 119 TCP Plain or STARTTLS.
NNTP over TLS 563 TCP The simplest choice for PBMessages.
BinkP and EMSI mail 24554 TCP FidoNet-style mail.
Inter-BBS who is online 11 UDP Only if inter-BBS messaging is on.
Inter-BBS messages 18 TCP Same.
Inter-BBS finger 79 TCP Optional, off by default.
PBLink QWK hub 21 and 50000 to 50040 TCP Only if you run a hub. It can share port 21 with PBFtp.

Two services cannot use the same port on the same protocol. After a change, restart the service in Service Management or restart PBDispatch.

Outgoing connections

Some features connect out to other servers. These normally need no firewall change.

Feature Goes to
Program updates, BBS list www.proboardbbs.com (HTTPS)
BBSLink games.bbslink.net on port 23, and an HTTP(S) handshake
DoorParty A local relay on 127.0.0.1, port 9999
Skull Crash sclink.xibalba.vip on ports 4443, 4514 and 4513
MRC chat The relay on port 5000
IRC Port 6667 or 6697
QWK and mail polling The uplink you configured