TCP Parameters
This topic lists some commonly used TCP port numbers and options that can be used when establishing connections.
Port Numbers
|
Port |
Protocol |
Comments |
|---|---|---|
|
7 |
echo |
|
|
11 |
systat |
|
|
15 |
netstat |
|
|
20 |
ftp-data |
|
|
21 |
ftp |
|
|
23 |
telnet |
|
|
25 |
smtp |
|
|
37 |
time |
|
|
43 |
whois |
|
|
53 |
domain |
DNS |
|
77 |
rje |
|
|
79 |
Finger |
|
|
80 |
http |
|
|
87 |
link |
ttylink |
|
95 |
||
|
101 |
hostnames |
|
|
109 |
pop-2 |
Post Office |
|
117 |
uucp-path |
|
|
119 |
nntp |
usenet - Network News Transfer |
|
123 |
ntp |
Network Time Protocol |
|
443 |
https |
Secure http |
|
465 |
ssmtp |
|
|
512 |
exec |
|
|
513 |
login |
|
|
514 |
shell |
cmd |
|
563 |
snntp |
Options
|
Value |
Meaning |
|---|---|
|
SO_BROADCAST |
Allow transmission of broadcast messages on the socket. |
|
SO_DEBUG |
Record debugging information. |
|
SO_DONTLINGER |
Don't block close waiting for unsent data to be sent. |
|
SO_DONTROUTE |
Don't route: send directly to interface. |
|
SO_KEEPALIVE |
Send keepalives. |
|
SO_LINGER |
Linger on close if unsent data is present. |
|
SO_OOBINLINE |
Receive out-of-band data in the normal data stream. |
|
SO_RCVBUF |
Specify buffer size for receives |
|
SO_REUSEADDR |
Allow the socket to be bound to an address that is already in use. |
|
SO_SNDBUF |
Specify buffer size for sends. |
|
TCP_NODELAY |
Disables the Nagle algorithm for send coalescing. |