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Module 10: Intermediate TCP/IP / Overview


Module 10: Intermediate TCP/IP
Overview

Routers use the IP address information in an IP packet header to determine the interface to which a packet should be switched based on its destination. Since IP does not ensure that the packet reaches the destination, it is described as an unreliable, connectionless protocol, that uses best-effort delivery. If packets are dropped in route, arrive in the wrong order, or are transmitted faster than the receiver can accept them, IP alone cannot correct the problem. To address these problems, IP relies on TCP. This module describes TCP and its functions and introduces UDP, another important Layer 4 protocol.
Each layer within the OSI reference model has various functions. These functions are independent of the other layers. Each layer expects to receive services from the layer beneath it, and each layer provides certain services to the layer above it. The application, presentation, and session layers of the OSI model, which are all considered to be part of the application layer in the TCP/IP model, access the services of the transport layer through logical entities called ports. This module will introduce the concept of ports and will explain the critical importance of ports and port numbers in data networking.
This module covers some of the objectives for the CCNA 640-801, INTRO 640-821, and ICND 640-811 exams. - 
Students who complete this module should be able to perform the following tasks: 
  • Describe TCP and its functions
  • Describe TCP synchronization and flow control
  • Describe UDP operation and processes
  • Identify common port numbers
  • Describe multiple conversations between hosts
  • Identify ports used for services and clients
  • Describe port numbering and well known ports
Understand the differences and the relationship between MAC addresses, IP addresses, and port numbers 

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