2.1 Compare and contrast Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) ports, protocols, and their purposes.

What does IP stand for?

Internet Protocol

What is at the beginning of a ethernet payload and at the end?

The beginning (from the client machine) is the Ethernet Header and at the end is the Ethernet trailer (Server machine).

On a ethernet payload what data is inside IP?

TCP data

On a ethernet payload what data is inside TCP?

HTTP data

How are TCP and UDP transported?

Encapsulated by the IP protocol.

What layer is TCP and UDP utilized on?

The OSI Layer 4 also called the transport layer.

What does TCP stand for?

Transmission Control Protocol

What type of protocol is TCP?

connection-oriented

Why is TCP considered "reliable" delivery?

Because it can manage out of order messages or retransmissions.

Does the TCP have flow control?

Yes and the receiver can manage how much data is sent.

What does UDP stand for?

User Datagram Protocol

Is UDP connection-oriented or connectionless?

connectionless

Why is UDP considered unreliable?

No error recovery and there is no reordering of data or retransmissions

Does UDP have flow control?

No because the send determines the amount of data transmitted,

Why would you ever use UDP?

Real-Time communication because there is no way to stop and resend the data. Also the time doesn't stop for your network.

What are the protocols that utilize UDP?

Dynamic Host Configuration Protocol (DHCP) and Trivial File Transfer Protocol (TFTP)

What is DHCP?

A protocol used to automate the assignment of IP Address. It stands for Dynamic Host Control Protocol.

What is TFTP?

Trivial File Transfer Protocol

What are the protocols that utilize TCP?

Hypertext Transfer Protocol Secure (HTTPS) and Secure Shell (SSH)

What is a port number?

Whenever a computer/server attempts to communicate with another computer/server over a network, it is necessary for the connection to be sent to both the correct IP address as well as the correct port number on that IP address. A given computer has 65535 ports that are each capable of running a service. Typically ports 1- 1023 are reserved for common communication protocols.

What are permanent port numbers called?

Non-ephemeral ports

What number range does permanent port numbers utilize?

Ports through 0 through 1,023 and usually is on a server or a service.

What are temporary port numbers called?

Ephemeral ports

What number range does temporary port numbers utilize?

Ports 1,024 and 65,535. These are determined in real-time by the client.

What are port numbers for?

Communication, not security

What protocols can utilize any number between 0 and 65,535?

TCP and UDP

Are TCP and UDP port numbers the same?

No. For example there can be one service on TCP Port 80 and a service on UDP Port 80.

How do firewalls make the decision to allow certain traffic?

Firewalls allow or reject certain traffic based on port numbers.

What information should you know about port numbers?

The port number, the protocol, and how that protocol is used.

What port numbers is by File Transfer Protocol (FTP)?

TCP 20 and TCP 21. TCP 20 is for data transfers and TCP 21 is used to control the data transfer.

What is the function of the File Transfer Protocol (FTP)?

Transfers files between systems. Also includes file management functions such add or removing files.

What port number does Secure Shell (SSH) use and what is its functionality?

TCP 22 and is a encrypted communication link

What port number is used by Telnet what is its functionality?

TCP 23. Can access devices remotely but in the clear communication which means not secure and anyone can see the information in these packets.

What port number does the Simple Mail Transfer Protocol (SMTP) use and what is its functionality?

TCP 25. Server to server email transfer. Also used to send mail from a device to a mail server.

What port number does the Domain Name System (DNS) use and what is the functionality?

UDP 53. Converts names to IP addresses. For example www.professormesser.com = 162.159.246.164

What port number does the Dynamic Host Configuration Protocol (DHCP) use and what is the functionality?

UDP 67 and UDP 68.

Automated configuration of IP address, subnet mask, and other options. If you use a public wifi like at a coffee shop then you are utilizing DHCP.

What port number does Hypertext Transfer Protocol (HTTP) use and what is the functionality?

TCP 80. Web server communication that is not encrypted.

What port number does Hypertext Transfer Protocol Secure (HTTPS) use and what is the functionality?

TCP 443. Web server communication that is encrypted.

What port number does the Post office Protocol version 3 (POP3) use and what is the functionality?

TCP 110 Receive emails from a single email client.

What port number does the Internet Message Access Protocol version 4 (IMAP4) use and what is the functionality?

TCP 143. Receives email from multiple email clients.

What does SMB stand for and what Operating System utilizes this protocol?

Server Message Block. Microsoft Windows and is also called Common Internet File System (CIFS).

What are the port numbers and function when using Network Basic Input/output System (NetBIOS) over TCP/IP?

UDP 137 NetBIOS name services finding the name of devices on the network.

TCP 139 NetBIOS session service to setup a session between devices.

What port number is used by SMB when it is communicating over TCP with NetBIOS?

TCP 445 (NetBIOS-less)

What are the ports used by Simple Network Management Protocol (SNMP) and what is the function of each of these ports?

UDP 161 Send a query for performance of a device

UDP 162 Monitors metrics and if anything exceeds those metrics an alert is given which are also called traps.

What versions of SNMP send information in a non encrypted form?

Version 1 and Version 2

What version of SNMP sends information in a encrypted form?

Version 3

What port number does Lightweight Directory Access Protocol (LDAP) use and what is the functionality?

TCP 389.

Queries directories

What port number does Remote Desktop Protocol (RDP) use and what is the functionality?

TCP 3389.

Shares a desktop remote connection with another desktop.