Technology - Internet 2 - TCP, UDP & SCTP

Synopsis

We explain TCP/IP’s UDP send and forget ‘datagram’ packets and TCP error-corrected two-way ‘pipes’, each with their 65,536 ports per IP address. We discuss how the 4 billion IPv4 address range is divided into subnets for LANs and other purposes. We also explain Network Address Translation (NAT), the new SCTP protocol and the adoption of IPv6 together with the current IP version 4.

Table of Contents

• 1. Synopsis
• 2. Introduction
• 3. TCP/IP packets
  • 3.1 IPv4 header
  • 3.2 Routing
    • 3.2.1 Dropping a packet
    • 3.2.2 The Routing Table
  • 3.3 UDP packet
  • 3.4 TCP
    • 3.4.1 TCP header
    • 3.4.2 TCP’s two-way ‘pipe’
    • 3.4.3 Three-way handshake
    • 3.4.4 TCP flow control
• 4. IP Addresses
  • 4.1 Overview
    • 4.1.1 4 billion IP addresses are not enough
  • 4.2 TCP and UDP port numbers
    • 4.2.1 Port numbers for major protocols
  • 4.3 Stream Control Transmission Protocol (SCTP)
    • 4.3.1 A new Transport Layer protocol
    • 4.3.2 Designed for VoIP
    • 4.3.3 Individual retransmissions per message stream
    • 4.3.4 Multihoming for redundancy
    • 4.3.5 Security
  • 4.4 Network and broadcast address
    • 4.4.1 Subnets
    • 4.4.2 Broadcast address
• 5. Transition to IPv6
  • 5.1 IPv6 islands in an IPv4 sea
  • 5.2 Dual stack networks
    • 5.2.1 Two separate address ranges
  • 5.3 Avoiding NAT – Network Address Translation
  • 5.4 IPv6 Benefits
    • 5.4.1 IPv6 Mobility
    • 5.4.2 IPv6 available in most operating systems
• 6. Related reports

• Exhibit 1 – An 8 address TCP/IP subnet