2.1 Ports & Protocols Flashcards
Internet protocol package
(Ethernet header, ip, tcp, http data, ethernet trailer)
TCP
Transmission control protocol
- Formal connection setup and close
- reliable, has recovery for errors
- flow control
- –> can manage how much data is sent, because TCP ack messages are sent
UDP
User datagram protocol
- connectionless, no formal open or close connection (no handshakes)
- unreliable
- no acknowledgement of data reception, no recovery
No flow control
- sender just decides how much to send
Packet transportation (IP)
- goes from IP address to another IP (house)
- MAC to enter lock in door
- room number - Port
Ipv4 sockets
Server IP address, protocol, server app port number
Client IP address, protocol, client port number
Non-ephermal ports-
permanent port #’s
Usually port numbers assigned to applications on server
Server ports: 0-1023
Ephermal ports
Temporary port numbers
Client ports: 1024 - 65 535
Chosen in realtime by client
TCP ports
Can range from 0 - 65,535
Udp ports
Can range from 0 - 65,535
FTP
File transfer protocol, transfers files between systems
Tcp/20 (active mode data port)
Tcp/21(controls communication)
Authentication:
- can use security username and password
- can use anonymously by typing in anonymous
Full featured functionality
-list,add,delete
SSH & port
Secure shell
Allows for encrypted communication on console level (ex. Command line)
Tcp/ Port 22
Telnet
Communication to console but not encrypted
Tcp/port 23
- not commonly used on network - outdated
SMTP
Simple mail transfer protocol
Used to send messages from a mobile device or server to server
-port: tcp/25
DNS & port
Domain name system
Converts names to IP addresses
Port: UDP/53
HTTP & port
Hypertext transfer protocol
Communication with web browser to web server
Port: tcp/80
