TCP/IP Flashcards
Class A Addresses
First Octet Value is 1-127
Subnet Mask is 255.0.0.0
of Hosts per network is 16,777,214
Class B Addresses
First Octet Value is 128-191
Subnet Mask is 255.255.0.0
of Hosts per network is 65,534
Class C Addresses
First Octet Value is 192-223
Subnet Mask is 255.255.255.0
of Hosts per network is 254
Class D Addresses
Used for multicasting applications
First Octet Value is 224-239
Has potential for 268,435,456 unique multicast groups that users can subscribe to from a multicast application.
Class E Addresses
Designed for experimental purposes
First Octet Value is 240-247
Port 20
FTP Data
Port used by FTP to send data to a client
Port 21
FTP Control
Port used by FTP commands sent to the server
Port 22
SSH
Port used by Secure Shell (SSH) to encrypt remote access communication. It typically is used as a secure replacement to Telnet.
Port 23
Telnet
Port used by Telnet to remotely connect to a system such as a server or router.
Port 25
SMTP
Port used to send Internet e-mail.
Port 53
DNS (Domain Name System)
Port used for DNS zone transfers
Port 80
HTTP
Internet protocol delivering web pages to the browser.
Port 110
POP3
Port used by POP3, which is the internet protocol to read e-mail.
Port 139
NetBIOS
Port used by the NetBIOS session service and is used to establish a connection between two systems for NetBIOS communication.
Port 143
IMAP
Port used by IMAP, which is a newer internet protocol to read e-mail.
