port : Java Glossary


The word port has at least three meanings:


TCP/IP Ports
Port name Port number
echo, used for testing. 7
DayTime, returns date/time as a string. 13
FTP (File Transfer Protocol) 20 and 21
SMTP (Simple Mail Transfer Protocol) 25
Time, returns 32-bit days since 1900/01/01. 37
DNS 53
POP3 (Post Office Protocol version 3) 110
NTP (Network Time Protocol)
64-bit number with 32 bits as the integer
and 32 bits as the fractional portion
of seconds since 1900/01/01.
utime 519
timed timeserver 525
SNTP (Simple Network Time Protocol) 580
dbAnywhere 8889
IN Windows Server 2003 you can find out which process in using which port with the Netstat -nao command.

Hardware Ports

At a hardware level are special registers called ports. When you write them you output to external I/O devices such as serial ports, parallel ports or hard disk controllers. When you read from them, you input from I/O devices.
Serial Port Assignments
com1: com2: com3: com4:
port: 3f8 2f8 3e8 2e8
irq: 4 3 4 3
Parallel Port Assignments
lpt1: lpt2: lpt3: LPT4: LPT5: LPT6: LPT7:
port: 3BC 378 278 368 268 358 258
irq: 7 5 ? ? ? ? ?
IANA list of TCP/IP Port Number Uses
UART: tool to check your serial port and IRQIRQ assignments

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