Networking Standards and Protocols Quiz

Internet Architecture Board (IAB)

• Serves as the technology advisory group for the Internet Society
• Responsible for the overall development of the protocols and architecture associated with the Internet

Internet Assigned Numbers Authority (IANA)

• Oversees Internet naming and addressing
• Manages all "unique parameters" on the Internet including IP (Internet Protocol) addresses

Organization for Standardization (ISO)

• International standards organization
• Responsible for a wide range of standards, many relevant to networking

Application Layer Protocols

• Application layer provides interfaces for application software so that applications can use network services
• Application layer protocol designates transport layer protocols and ports

Simple Mail Transfer Protocol (SMTP)

• TCP/IP protocol that defines reliable and efficient transfer of electronic mail service on the Internet

Post Office Protocol, version 3 (POP3)

• TCP/IP protocol that allows workstations to retrieve mail held by the server

Trivial File Transfer Protocol (TFTP)

• Small and simple alternative to FTP that uses UDP to transfer files between systems

File Transfer Protocol (FTP)

• TCP/IP protocol for sharing computer programs and/or data between hosts over a TCP/IP network
• Uses TCP to create a virtual connection for control information and a separate TCP connection for data transfer

Network File System (NFS)

• TCP/IP protocol that allows computers to mount remote drives
• Operates drives as if they were local drives

Domain Name System (DNS)

• TCP/IP protocol used for translating names of domains and network nodes into IP addresses

Simple Network Management Protocol (SNMP)

• TCP/IP protocol for monitoring and controlling the exchange of management information between networks and components
• Enables network administrators to manage configurations, statistics collection, network performance, and security
• Has three components:
  • Managed devices: Collect and store management information and make it available to NMSs using SNMP
  • Agent: Has local knowledge of management information and translates it into a form compatible with SNMP
  • NMS: Executes applications that monitor and control managed devices, providing the bulk of processing and memory resources for network management

Terminal Emulation Protocol Network (Telnet)

• TCP/IP protocol using TCP to establish a connection between server and client
• Uses a daemon, referred to as a remote host
• A Telnet connection is called a Virtual Terminal (VTY) session

Remote login application (rlogin)

• UNIX command that allows authorized users to log in to other UNIX machines (hosts) on a network
• Users can interact as if they were physically at the host computer
• Users can access files, read, edit, or delete them

Hypertext Transfer Protocol (HTTP)

• Application-level protocol service and Internet standard developed by the IETF
• Supports the exchange of information on the World Wide Web and internal networks

HTTPS (Hypertext Transfer Protocol over Secure Socket Layer)

• Secure message-oriented communications protocol used with HTTP
• Secure Sockets Layer (SSL) is a security protocol that works at a socket level between the TCP layer and the application layer encrypting/decoding data and authenticating entities

TCP and UDP Connections

• Computers on the Internet communicate using either the Transmission Control Protocol (TCP) or the User Datagram Protocol (UDP)

Transport Control Protocol (TCP)

• Connection-oriented TCP/IP standard transport layer protocol
• Provides reliable data delivery, duplicate data suppression, congestion control, and flow control
• Many application protocols depend on it
• Transport protocols deliver information from one port to another, enabling communication between application programs
• Reliability is ensured through error-detection and error-correction mechanisms implemented within TCP

User Datagram Protocol (UDP)

• Connectionless TCP/IP standard transport layer protocol
• Provides unreliable, best-effort service
• Sends independent packets of data (datagrams) from one computer to another with no guarantees about arrival

Port Numbers

• Data transmitted over the Internet includes addressing information identifying the computer and port for which it is destined
• The computer is identified by its 32-bit IP address
• TCP and UDP use ports identified by 16-bit numbers to deliver data to a specific application
• Range from 0 to 65,535 as they are represented by 16-bit numbers
• Ports 0-1023 are reserved for well-known services like HTTP and FTP, as well as system services

TCP and UDP Formats

• TCP Header Fields

  • Source Port: Identifies the application sending the segment (16 bits)
  • Destination Port: Identifies the application receiving the segment (16 bits)
  • Sequence Number: Refers to each byte of data sent over a TCP connection. The value equals the sequence number of the first byte in a sent segment (32 bits)
  • Acknowledgment Number: Indicates the sequence number of the next segment's first byte the receiver expects (32 bits)
  • Header Length: Indicates the length of the TCP header (32 bits)
  • Reserved: Always set to 0 for future protocol changes (6 bits)
  • Control Bits: Include FIN, ACK, and SYN flags indicating TCP data segments in different states
  • Window: Used for TCP flow control. Value is the maximum number of bytes allowed by the receiver
  • Checksum: Calculated and stored by the sender and verified by the receiver (16 bits)

• UDP Header Fields

  • Source Port: Identifies the application that sends the segment (16 bits)
  • Destination Port: Identifies the application that receives the segment (16 bits)
  • Length: Specifies the total length of the UDP header and data. The minimum length is 8 bytes (16 bits)
  • Checksum: Checksum of the UDP header and UDP data (16 bits)

SYN-ACK Handshake

• Three-way handshake method used by the sender and receiver to inform their operating systems that a connection will be initiated before actual data communication
• SYN: Synchronize
• ACK: Acknowledge
• FIN: Finish
• Sequence Number and Acknowledgment Number fields implement reliable and ordered data transmission
• Window Sliding Mechanism required by the sender to receive an acknowledgment from the receiver after transmitting a certain amount of data
• Used by TCP to control the data transmission rate

TCP Shutdown (Four-Way Handshake)

• Engaged when data transmission is complete to disconnect the TCP connection and release system resources

Test your knowledge on the essential organizations and protocols that govern internet architecture, including the IAB, IANA, and ISO. Delve into application layer protocols like SMTP and POP3, and understand their roles in network communication.