Computer Networks

In the TCP/IP model, a port number serves as the transport service access point. It allows the transport layer to distinguish between different applications or services running on the same host.

Video streaming typically uses UDP because it prioritizes speed and real-time delivery over the error correction and retransmission overhead inherent in TCP. Using TCP for live streaming often results in unacceptable latency.

TCP is a connection-oriented protocol that uses a three-way handshake to establish a reliable session, and it processes data streams from the application layer.

TCP includes mechanisms for error recovery, flow control, and retransmission, which add overhead and latency. UDP lacks these mechanisms, making it faster but less reliable.

UDP is connectionless because it does not establish a session before sending data. Each datagram is treated as an independent unit by the transport layer, with no relationship to previous or subsequent packets.

The transport layer is responsible for end-to-end communication, including error recovery, flow control, and segmentation to ensure reliability when required by the application.

SCTP (Stream Control Transmission Protocol) is a transport layer protocol designed to provide reliable, message-oriented communication. ICMP and NDP are network layer protocols, and DHCP is an application layer protocol.

Online gaming requires low latency, so it frequently uses UDP to avoid the delays caused by TCP's retransmission and congestion control mechanisms.

TCP and UDP are the two primary transport layer protocols in the TCP/IP suite. FTP and HTTP are application layer protocols.

The transport layer receives data from multiple applications and encapsulates it into segments, which are then passed down to the network layer for routing.

In the OSI model, the Protocol Data Unit (PDU) for the Network layer (Layer 3) is indeed called a packet.

Encapsulation at Layer 3 involves adding an IP header to the data segment received from the transport layer, forming an IP packet.

IPX stands for Internetwork Packet Exchange, a protocol used in early networking environments like Novell NetWare.

IGMP (Internet Group Management Protocol) is used by hosts and adjacent routers to establish and manage multicast group memberships.

The primary purpose of the Internet Protocol (IP) is to provide logical addressing and routing for packets across interconnected networks. While IP facilitates routing, its fundamental role is defining the addressing scheme that allows data to be directed to the correct destination.