Tech Esoterica – Networking

IP Addresses

Modem IPv4 default (most of the time):

  • 192.168.0.1
  • 192.168.1.1
  • 192.168.2.1
  • 10.0.0.1
  • 10.0.0.1

Ports

Blocked ports:

PortProtocol/IP versionDescription
0TCP, IPv4/6Reserved port, not meant to be used, but has been abused
25TCP SMTP, IPv4/6unsecured, botnets use it for spam, use port 587 instead
67UDP BOOTP/DHCP, IPv4gets IPv4 info from DHCP server and is vulnerable to attacks
135-139TCP/UDP NetBios, IPv4/6allows file sharing over networks and bad permissions can give full access to a remote client
161UDP SNMP, IPv4/6vulnerable to DDoS attacks
445TCP MS-DS/SMB, IPv4/6vulnerable to exploits/attacks/malware (e.g., Sasser/Nimda worms)
520UDP RIP, IPv4vulnerable to malicious route updates, gives several attack possibilities
547UDP DHCPv6, IPv6gets IPv6 info from DHCP server and is vulnerable to attacks
1080TCP SOCKS, IPv4/6vulnerable to many things
1900UDP SSDP, IPv4/6vulnerable to DoS attacks

Standard internet ports:

ServiceTCP PortUDP Port
DHCP67, 68, 135
DNS53, 13953
HTTP / HTTP-SSL80 / 443
IIS80
LDAP / LDAP-SSL389 / 636
NetBIOS139138
NTP123
RPC135, 1500, 2500
SNMP / SNMP Trap161161 / 162
Telnet / SSH, SFTP23 / 22

File-specific ports

ServiceTCP PortUDP Port
CIFS445139, 445
FTP / FTP-data / FTP over SSL / FTP over TLS21 / 20
File shares session139
TFTP69
MySQL3306
SQL53, 13753, 135, 139, 1024-5000
WebDAV, CalDAV / WebDAV(HTTPS), CalDAV (HTTPS)5005 / 5006

Mail/chat-related ports:

ServiceTCP Port
SMTP / SMTP-SSL / SMTP-TLS25 / 465 / 587
POP3 / POP3-SSL110 / 995
IMAP / IMAP-SSL143 / 993
NNTP / NNTP-SSL119 / 563
IRC531
X.400102

Proprietary ports:

ServiceVendorTCP PortUDP Port
BonjourApple5353
iTunes ServerApple3689
Macintosh File Services (AFP/IP)Apple548
Microsoft ChatMicrosoft6665, 6667
Microsoft Message QueueMicrosoft135, 1801, 2101, 2103, 21051801, 3527
Microsoft NetMeetingMicrosoft389, 1720, 1731

Authentication ports:

ServiceTCP PortUDP Port
Kerberos88, 464, 543, 54, 205388, 464
RADIUS1812, 1812, 1645, 1646
VPN – OpenVPN1194
VPN – PPTP1723
VPN – L2TP/IPSec500, 1701, 4500