Domain 1.5 Flashcards
Describe UDP and TCP
UDP uses Datagrams to move data.
TCP uses segments to move data.
- Both UDP & TCP belong to Layer 4 of the OSI model.
- TCP and UDP data are encapsulated using the Internet Protocol or (IP) in order to be sent across the network
Both protocols support multiplexing, which allows for a single host to make use of both protocols simultaneously with different applications.
Describe TCP
Connection Orientated
3-Way handshake for establishing connections
Has error detection and correction
Has packet sequencing
Makes use of acknowledgement reply from recipient. This allows for packet resubmission due to loss or corruption
Flow control possible with windowing through use of Acknowledgement from recipient.
Descript UDP
Connection-less protocol
No error detection or correction
No flow control
No re-ordering of data
What are the well known ports or Non-Ephemeral ports
Ports: 0-1023
What are the Ephemeral ports, and how is their use determined
Ports: 1024-65,535
Real time use is determined by the clients using the port numbers.
What is ICMP
Internet Control Message Protocol -
“text messaging for network devices”
- Protocol carried by IP, not used for data transfer
-Allows devices to send and reply to administrative requests (ping and response from target)
-Devices can send messages when things do go well.
What is Telnet, and which port(s) does it use
TCP/23
Remote console access for devices
Sends data in the clear
What is SSH, and which port(s) does it use
TCP/22
Used for secure connections to host devices. This allows for a remote CLI session to be established.
Makes use Encryption
What is DNS, and which port(s) does it use
DNS UDP/53
Converts Names to IP addresses
Large transfers may use TCP/53
What is SMTP, and which port(s) does it use
Simple Mail Transfer Protocol TCP/25
Server to Server mail transfer
Also used to send mail from a device to a mail server.
Commonly configured on mobile devices and email clients
Other protocols are uses to receive email (IMAP, POP3)
What is IMAP, and what port does it use
Internet message Access protocol 4
TCP/143
Allows the management of an email inbox from multiple clients
EX: delete email from mailbox on phone, IMAP allows update to be reflected on a desktop email client.
What is POP3 and what port does it use
Post Office Protocol 3 TCP/110
Basic Mail Transfer Functionality
What is SFTP and what port does it use
TCP/22 Secure FTP
Makes use of the SSH protocol to send encrypted file transfer.
Provides File System Functionality:
Resume interrupted file transfers, Directory listings remote file removal
What is FTP and which ports does it use
TCP/20 for Active mode Data
TCP /21 for Control
-Transfers files between systems
-Authenticates with username and password
- Full featured File System functionality (list, add, delete)
What is TFTP? and which ports does it use
Trivial FTP UDP/69
-Very simple file transfer:
Read Write
-No authentication, so not common in production systems