Section 4: TCP/IP Model Flashcards
Which port does File Transfer Protocol (FTP) connect to and what is the protocol’s usage?
Port: 21,22
Usage: Provides Insecure file transfers
Which port does Secure Shell (SSH) connect to and what is the protocol’s usage?
Port: 22
Usage: Provides secure remote control of another machine using a text-based environment
Which port does Secure File Transfer Protocol (SFTP) connect to and what is the protocol’s usage?
Port: 22
Usage: Provides secure file transfers
Which port does Telnet connect to and what is the protocol’s usage?
Port: 23
Usage: Provides insecure remote control of another machine using a text-based environment
Which port does Simple Mail Transfer Protocol (SMTP) connect to and what is the protocol’s usage?
Port: 25
Usage: Provides the ability to send emails over the network
Which port does Domain Name System (DNS) connect to and what is the protocol’s usage?
Port: 53
Usage: Converts domain names to IP addresses, and IP address to domain names
Which port does File Dynamic Host Control Protocol (DHCP) connect to and what is the protocol’s usage?
Port: 67,68
Usage: Automatically provides network parameteres to your clients, such as their IP address, subnet mask, default gateway, and the DNS server they should use
Which port does Trivial File Transfer Protocol (TFTP) connect to and what is the protocol’s usage?
Port: 69
Usage: Used as a lightweight file transfer method for sending configuration files or network booting of an operating system
Which port does Hypertext transfer protocol (HTTP) connect to and what is the protocol’s usage?
Port: 80
Usage: Used for insecure web browsing
Which port does Post Office Protocol Version Three (POP3) connect to and what is the protocol’s usage?
Port: 110
Usage: Used for receiving incoming emails
Which port does Network Time Protocol (NTP) connect to and what is the protocol’s usage?
Port: 123
Usage: Used to keep accurate time for clients on a network
Which port does Network Basic Input/Output System (NetBIOS) connect to and what is the protocol’s usage?
Port: 139
Usage: Used for file or printer sharing in a Windows Network
Which port does Internet Mail Application Protocol (IMAP) connect to and what is the protocol’s usage?
Port: 143
Usage: A newer method of retrieving incoming emails which improves upon older POP3
Which port does Simple Network Management Protocol (SNMP) connect to and what is the protocol’s usage?
Port: 161,162
Usage: Used to collect data about network devices and monitor their status
Which port does Lightweight Directory Access Protocol (LDAP) connect to and what is the protocol’s usage?
Port: 389
Usage: Used to provide directory services to your network
Which port does Hypertext Transfer Protocol -Secure (HTTPS) connect to and what is the protocol’s usage?
Port: 443
Usage: Used for secure browsing
Which port does Server Message Block (SMB) connect to and what is the protocol’s usage?
Port: 445
Usage: Used for Windows file and printer sharing services
Which port does System Logging Protocol (SysLog) connect to and what is the protocol’s usage?
Port: 514
Usage: Used for logging data back to centralized server
Which port does Simple Mail Transfer Protocol Transport Layer Security (SMTP TLS) connect to and what is the protocol’s usage?
Port: 587
Usage: Secure and encrypted way to send emails
Which port does Lightweight Directory Access Protocol - Secure (LDAPS) connect to and what is the protocol’s usage?
Port: 636
Usage: Provides secure directory services
Which port does Internet Message Access Protocol over SSL (IMAP over SSL) connect to and what is the protocol’s usage?
Port: 993
Usage: Secure and encrypted way to receive emails
Which port does Post Office Protocol Version 3 over SSL (POP3 over SSL) connect to and what is the protocol’s usage?
Port: 995
Usage: Secure and encrypted way to receive emails
Which port does Structured Query Language Server Protocol (SQL) connect to and what is the protocol’s usage?
Port: 1433
Usage: Used for communication from a client to a database engine
Which port does SQLnet Protocol connect to and what is the protocol’s usage?
Port: 1521
Usage: Used for communication from a client to an Oracle database
Which port does MYSQL connect to and what is the protocol’s usage?
Port: 3306
Usage: Used for communication from a client to the MYSQL database engine
Which port does File Remote Desktop Protocol (RDP) connect to and what is the protocol’s usage?
Port: 3389
Usage: Provides graphical remote control of another client or server
Which port does Session Initiation Protocol (SIP) connect to and what is the protocol’s usage?
Port: 5060, 5061
Usage: Used to initiate VoIP and video calls
What are the different layers in order in the TCP/IP model? Start with layer 1.
- Network Interface
- Internet
- Transport
- Application
What does the Network Interface layer do in the TCP/IP model?
Describes how to transmit bits accross a network and determines how the network medium is going to be used. Like twister pair copper cable, CoAxial Cable, wireless etc.
What does the Internet layer do in the TCP/IP model?
The Internet layer is where data is taken and packaged into IP datagrams. Protocols include ARP, IP, ICMP, Reverse ARP etc.
What does the Transport layer do in the TCP/IP model?
Defines the level of service and the status of the connection being used by TCP, UDP, or RTP
What does the Application layer do in the TCP/IP model?
Dictates how programs are going to interface with the transport layer by conduction session management. The protocols in this layer are HTTP, SNMP, DNS, FTP, Telnet, SSH, SMTP, SSL/TLS etc.
What is a Port?
A Port is a logical opening on a system representing a service or application that’s listening and waiting for traffic. Ports are numbered from 0 - 65535.
What range of ports are Well-Known/Reserved Ports?
Ports 0 - 1023
What are Ephemeral Ports?
Ephemeral ports are short lived temporary ports that are opened for short period of time for pre defined ranges.
What range of ports are Ephemeral Ports?
Ports 1024 - 65535
What information does a IPv4 packet consists of?
source address, destination address, IP flags and protocols
What are the sizes of a TCP and a UDP header?
TCP Header: 20 bytes
UDP Header: 8 bytes
What tool can be used to scan for open ports?
Nmap
How does a Transmission Control Protocol (TCP) work?
By conducting a three-way handshake between a client and a server, thereby establishing a connection
Please Answer true or false.
1. TCP is a connection-oriented protocol
2. Sender cannot resend a packet if the end user did not receive a packet
3. UDP can detect if packets are corrupted when they are received by a client
4. UDP is reliable than TCP
- True
- False
- True
- False
What is an Internet Control Message Protocol (ICMP)?
A Protocol used to communicate information about network connectivity issues back to the sender
True or False.
Does “ping” use the ICMP protocol?
True
What is a Genereic Routing Encapsulation (GRE) protocol?
A protocol used as a simple and effective way to create a tunnel, called a GRE tunnel, over a public network.
Does a GRE tunnel provide encryption?
No
What is an alternative protocol that can create a tunnel over a public network and also provide encryption?
Internet Protocol Security (IPSec)
What is an Internet Protocol Security (IPSec)?
A set of secure network communication protocols that operates at the network or packet processing layer and is used to protect one or more data flows between peers.
What are the two underlying protocols of IPSec?
- Authentication Header (AH)
- Encapsulating Security Payload
What is the Authentication Header (AH) in IPSec?
A protocol that provides integrity and authentication
What is Encapsulating Security Payload (ESP) in IPSec?
Provides encryption and integrity for the data packets sent over IPSec