OV Copyright © 2011 Element K Content LLC. All rights reserved. TCP/IP Addressing and Data Delivery  The TCP/IP Protocol Suite  IP Addressing  Default IP Addressing Schemes  Create Custom IP Addressing Schemes  Implement IPv6 Addresses  Delivery Techniques

OV Copyright © 2011 Element K Content LLC. All rights reserved. TCP TCP/IP is the native Protocol of the Internet and is required for Internet connectivity. Transmission Control Protocol (TCP):  Is part of the TCP/IP Protocol Suite along with another Transport-layer protocol - User Datagram Protocol (UDP)  Is a connection-oriented, guaranteed-delivery protocol used to send data packets between computers over the Internet.  Is part of the Internet protocol suite along with the Internet Protocol (IP)  Is responsible for breaking up data into datagrams, reassembling them at the other end, resending data lost in transit, and resequencing data. IP is responsible for routing individual datagrams and addressing.

OV Copyright © 2011 Element K Content LLC. All rights reserved. IP Internet Protocol (IP):  A Network-layer protocol that is responsible for routing individual datagrams and addressing.  A connectionless protocol and acts as an intermediary between higher protocol layers and the network.  Makes no guarantees about packet delivery, corruption of data, or lost packets.  Works in concert with TCP, which establishes a connection between a source and the destination.

OV Copyright © 2011 Element K Content LLC. All rights reserved. The IP Data Packet Delivery Process Application Transport Internet Network Interface TCP/IP model Passes IP address to Internet layer Passes IP address to Internet layer 3 3 Uses subnet mask to determine the network of the receiving node Uses subnet mask to determine the network of the receiving node Service establishes connection and resolves the name Service establishes connection and resolves the name

OV Copyright © 2011 Element K Content LLC. All rights reserved. UDP User Datagram Protocol (UDP) or Universal Datagram Protocol:  Is a connectionless Transport-layer protocol in the Internet Protocol suite  Is a best-effort delivery protocol that is used with IP like TCP  Transmits data and ensures data integrity as TCP, but lacks reliability, flow- control, and error-recovery functions.  Is less complex than TCP and because it is connectionless, provides faster service

OV Copyright © 2011 Element K Content LLC. All rights reserved. ARP Address resolution in ARP is performed by the following three steps:  ARP receives an IP address from IP.  If ARP has the MAC address in its cache, it returns it to IP. If not, it issues a broadcast to resolve the IP address.  A target node with the corresponding IP address responds with a unicast that includes its MAC address.

OV Copyright © 2011 Element K Content LLC. All rights reserved. ICMP Sending NodeReceiving Node Data Receiving Node Buffers Fill Source Quench Message Flood warning Flood warning

OV Copyright © 2011 Element K Content LLC. All rights reserved. IGMP IGMP is used for multicast packet routing IGMP is used for multicast packet routing IGMP

OV Copyright © 2011 Element K Content LLC. All rights reserved.  The header part contains the destination and source addresses.  The footer part contains an error checking code.  The data part contains the actual information or data that is to be transmitted. Data Packets Header Footer Data

OV Copyright © 2011 Element K Content LLC. All rights reserved. A network address typically includes two parts: one that identifies the network, and the other that identifies a node on the network. Network Addresses Network portion Node portion

OV Copyright © 2011 Element K Content LLC. All rights reserved. Network Names Descriptive host name IP address mapping

OV Copyright © 2011 Element K Content LLC. All rights reserved. IP Addresses 32-Bit Binary Address Network Address (NA) portion Host Address (HA) Portion

OV Copyright © 2011 Element K Content LLC. All rights reserved. Subnets  The process of logically dividing a network into smaller subnetworks or subnets, with each subnet having a unique address.  The conventional addressing technique has IP addresses with two hierarchical levels, namely network ID and host ID. Subnet A Subnet B Network is divided into smaller subnetworks

OV Copyright © 2011 Element K Content LLC. All rights reserved. Subnet Masks IP address Network address Subnet mask differentiates the network and node portions of the binary IP address Subnet mask differentiates the network and node portions of the binary IP address Node portion Network portion Subnet mask removes the node portion Subnet mask removes the node portion

OV Copyright © 2011 Element K Content LLC. All rights reserved. Subnet Mask Structure  The ones in the mask always start at bit 32, to the left of the mask.  The zeros in the mask always start at bit 1, to the right of the mask.  The ones in the mask must be contiguous, with no zeros interspersed between the ones.

OV Copyright © 2011 Element K Content LLC. All rights reserved. IP Address Assignment Rules TCP/IP

OV Copyright © 2011 Element K Content LLC. All rights reserved. Binary and Decimal Conversion = 255 Binary number Binary place value Decimal equivalent

OV Copyright © 2011 Element K Content LLC. All rights reserved. Binary ANDing Subnet mask in binary IP address in binary ANDing Network ID IP address Subnet mask Masks the node portion of the IP address Masks the node portion of the IP address Network portion Node portion

OV Copyright © 2011 Element K Content LLC. All rights reserved. ICANN ICANN Companies lease IP addresses from ICANN

OV Copyright © 2011 Element K Content LLC. All rights reserved. IP Address Classes Address ClassDescription Class A Provides a small number of network addresses for networks with a large number of nodes per network.  Address range: to  Number of networks: 126  Number of nodes per network: 16,777,214  Network ID portion: First octet  Node ID portion: Last three octets  Default subnet mask: Class B Provides a balance between the number of network addresses and the number of nodes per network.  Address range: to  Number of networks: 16,382  Number of nodes per network: 65,534  Network ID portion: First two octets, excluding Class A addresses  Node ID portion: Last two octets  Default subnet mask:

OV Copyright © 2011 Element K Content LLC. All rights reserved. IP Address Classes (Cont.) Address ClassDescription Class C Provide a large number of network addresses for networks with a small number of nodes per network.  Address range: to  Number of networks: 2,097,150  Number of nodes per network: 254  Network ID portion: First three octets, excluding Class A and Class B addresses  Node ID portion: Last octet  Default subnet mask: Class D Addresses are set aside to support multicast transmissions. Any network can use them, regardless of the base network ID.  Address range: to Example of a Class D address: Class E Addresses that are set aside for research and experimentation.  Address range: to Example of a Class E address:

OV Copyright © 2011 Element K Content LLC. All rights reserved. Private IP Addresses  Private IP addresses are addresses that organizations use for nodes requiring IP connectivity within enterprise networks, but not requiring external connections to the Internet.  IP addresses in each of the Classes A, B, and C are reserved as private IP addresses.

OV Copyright © 2011 Element K Content LLC. All rights reserved. The Local and Remote Addressing Process Node uses a subnet mask to determine the destination of packet Node applies subnet mask to its own IP address Node applies the subnet mask to the packet's destination address The node compares the two network IDs Are they the same? Two nodes are on the same subnet Two nodes are remote to each other Yes No

OV Copyright © 2011 Element K Content LLC. All rights reserved. Default Gateways Gateway Default gateway is the address of the router connected to the Internet Default gateway is the address of the router connected to the Internet

OV Copyright © 2011 Element K Content LLC. All rights reserved Custom TCP/IP Subnets Custom subnet mask Routes traffic between subnets Routes traffic between subnets A class of leased addresses that are divided into smaller groups A class of leased addresses that are divided into smaller groups

OV Copyright © 2011 Element K Content LLC. All rights reserved. Custom Subnet Masks Class C network address Class C network address Custom subnet mask Custom subnet mask Borrowed bits from the left side of the node Borrowed bits from the left side of the node

OV Copyright © 2011 Element K Content LLC. All rights reserved. Variable Length Subnet Masks Subnet 1 6 addresses Subnet 2 14 addresses Subnet 3 30 addresses 5 nodes nodes nodes

OV Copyright © 2011 Element K Content LLC. All rights reserved. Classless Inter Domain Routing /23 CIDR notation combines a network address with a number to represent the number of one bits in the mask. CIDR combines the network address with a number CIDR combines the network address with a number

OV Copyright © 2011 Element K Content LLC. All rights reserved. IPv4 Address Space Limitations Limitations of the IPv4 address space include:  The 32-bit IP address space itself, which provides only a theoretical maximum of 2 32, or approximately 4,295 billion, separate addresses.  The division of the address space into fixed classes; addresses falling either between classes or between subnets are unavailable for assignment.  IP address classes provide a small number of node addresses, leading to difficulty matching IP address leases to a company's needs.  The depletion of Class A and Class B IP address assignments.  Unassigned and unused address ranges within existing Class A and Class B blocks.

OV Copyright © 2011 Element K Content LLC. All rights reserved. IPv6 IPv6:  Is the successor to IPv4, an addressing scheme that increases the available pool of IP addresses by implementing a 128-bit binary address space.  Includes new efficiency features.  Is incompatible with IPv4.

OV Copyright © 2011 Element K Content LLC. All rights reserved. IPv6 Addresses  An IPv6 address is a 128-bit binary number assigned to a computer on a TCP/IP network.  Some of the bits in the address represent the network segment; the other bits represent the host.  For readability, the IPv6 address is usually separated by colons into eight groups of four hexadecimal digits.

OV Copyright © 2011 Element K Content LLC. All rights reserved. Implement IPv6 Addresses To implement IPv6 on an IPv4 network, follow these guidelines:  Implement IPv6 in phases throughout the organization.  Ensure interoperability between IPv4 and IPv6 during the initial phase of the transition from IPv4 to IPv6.  Avoid using subnet masks while migrating your network to IPv6 as it is not necessary to use subnet masks.  Remember that the network classes used in IPv4 will not apply to IPv6.  Configure AAAA DNS records for IPv6 although IPv4 DNS services make use of A records.  Upgrade the necessary hardware to support IPv6. This includes all nodes, hosts, and routers on the network.  Ensure that the IPv6 environment, once implemented, is scalable to support the future requirements of your network.  Ensure that IPv6 packets that are sent on an IPv4 network are encapsulated. This can be done by tunneling.

OV Copyright © 2011 Element K Content LLC. All rights reserved. Connections A connection:  Is a virtual link between two nodes established for the duration of a communication session.  Provides flow control, packet sequencing, and error recovery functions to ensure reliable communications between nodes.

OV Copyright © 2011 Element K Content LLC. All rights reserved. Flow Control The following are common flow-control techniques:  Buffering  Data windows  Fixed and sliding windows

OV Copyright © 2011 Element K Content LLC. All rights reserved. Buffering  A flow control technique in which data received is stored on a buffer.  Is used when reading information from the disk or RAM.

OV Copyright © 2011 Element K Content LLC. All rights reserved. Data Windows 10 1 Without data windows With data windows Packet ACK Defines how much data can be sent without waiting for an acknowledgment Defines how much data can be sent without waiting for an acknowledgment

OV Copyright © 2011 Element K Content LLC. All rights reserved. Error Detection Data sent with EDC in footer Receiver generates an EDC and compares it with the one sent in the footer Do they match? Process data YesNo Request data be retransmitted

OV Copyright © 2011 Element K Content LLC. All rights reserved. Parity Check Compare bytes with parity bits Compare bytes with parity bits Parity bit 1 1 SenderReceiver Sender adds one bit to each word of data Sender adds one bit to each word of data 2 2 Receiver compares the transmitted and received bytes Receiver compares the transmitted and received bytes 3 3 If there is a mismatch, the receiver requests retransmission If there is a mismatch, the receiver requests retransmission

OV Copyright © 2011 Element K Content LLC. All rights reserved. CRC Cyclic Redundancy Check Compare CRCs for error CRC Sender attaches CRC to data Sender attaches CRC to data 2 2 Receiver calculates CRC for received block Receiver calculates CRC for received block 3 3 Values match and data is unaltered Values match and data is unaltered

OV Copyright © 2011 Element K Content LLC. All rights reserved. Reflective Questions 1. In your opinion, which class of IP address will suit your organization? 2. Which delivery techniques will you implement most often on your network?