ov 6 - 1 copyright © 2011 element k content llc. all rights reserved. tcp/ip addressing and data...

OV 6 - 1Copyright © 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


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.


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.


The IP Data Packet Delivery Process

203.175.10.25255.255.255.0

203.175.10.50255.255.255.0Application

Transport

Internet

Network Interface

TCP/IP model

1

2 Passes IP address to Internet layer 3 Uses subnet mask to determine

the network of the receiving node

Service establishesconnection and

resolves the name


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


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.


ICMP

Sending Node Receiving Node

3

21 Data Receiving Node Buffers Fill

Source Quench Message

Floodwarning


IGMP

IGMP is used for multicast packet routing

IGMP


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


A network address typically includes two parts: one that identifies thenetwork, and the other that identifies a node on the network.

Network Addresses

192.168.100.100

Network portion

Node portion


Network Names

Descriptive host name

IP address mapping


IP Addresses

32-Bit Binary Address

10101100.00010000.00101000.00000000

Network Address (NA) portion Host Address (HA) Portion


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


Subnet Masks

1101100.00001000.00001010.01100101

11111111.11111111.00000000.00000000

1101100.00001000.00000000.00000000

IP address

Network address

Subnet mask differentiates the network and node portions

of the binary IP address

Node portionNetwork portion

Network portion Subnet mask removes the node portion


Subnet Mask Structure

11111111.11111111.11111111.00000000

255.255.255.0

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.


IP Address Assignment Rules

TCP/IP139.80.100.10255.255.0.0

139.80.100.20255.255.0.0

139.90.100.10255.255.0.0

139.90.50.20255.255.0.0


Binary and Decimal Conversion

1 1 1 1 1 11 1

2 2 2 2 2 22 2

64 32 16 8 4 2128 1

7 06 5 4 3 2 1

+ + + + + + + = 255

Binary number

Binary place value

Decimal equivalent


Binary ANDing

Subnet mask in binary

10001011.01010111.10001100.01001100

11111111.11111111.11111111.00000000

10001011.01010111.10001100.00000000

IP address in binary

ANDing

Network ID

139.87.140.76IP address

Subnet mask 255.255.255.0

139.87.140.0

Masks the node portionof the IP address

Network portion Node portion


ICANN

139.80.0.0 208.123.45.0

ICANN

Companies lease IP addresses from ICANN


IP Address Classes

Address Class Description

Class A

Provides a small number of network addresses for networks with a large number of nodes per network. Address range: 1.0.0.0 to 127.255.255.255 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: 255.0.0.0

Class B

Provides a balance between the number of network addresses and the number of nodes per network. Address range: 128.0.0.0 to 191.255.255.255 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: 255.255.0.0


IP Address Classes (Cont.)

Address Class Description

Class C

Provide a large number of network addresses for networks with a small number of nodes per network. Address range: 192.0.0.0 to 223.255.255.255 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: 255.255.255.0

Class D

Addresses are set aside to support multicast transmissions. Any network can use them, regardless of the base network ID. Address range: 224.0.0.0 to 239.255.255.255Example of a Class D address: 230.43.160.48

Class EAddresses that are set aside for research and experimentation. Address range: 240.0.0.0 to 255.255.255.255Example of a Class E address: 250.217.39.190


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.


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


Default Gateways

139.87.10.9

139.87.10.10

139.115.30.0

Gateway

Default gateway is the address of the router

connected to the Internet


203.175.10.1 - 62

255.255.255.192

203.175.10.65 - 126

255.255.255.192

203.175.10.128 - 190

255.255.255.192

203.175.10.193 - 254

255.255.255.192

Custom TCP/IP Subnets

203.175.10.0Custom subnet mask

Routes traffic between subnets

A class of leased addresses that are divided into smaller groups


Custom Subnet Masks

203.175.10.0

11001011.10101111.00001010.00000000

255.255.255.192

11111111.11111111.11111111.11000000

Class C networkaddress

Custom subnetmask

Borrowed bits fromthe left side of the node


Variable Length Subnet Masks

203.175.10.0255.255.255.254

Subnet 1

6 addresses

Subnet 2

14 addresses

Subnet 3

30 addresses

5 nodes

255.255.255.248

12 nodes

255.255.255.240

28 nodes

255.255.248.0


Classless Inter Domain Routing

192.168.12.0

255.255.255.0

192.168.13.0

255.255.255.0

192.168.12.0

255.255.254.0192.168.12.0/23

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


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 232, 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.


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.


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.


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.


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.


Flow Control

The following are common flow-control techniques: Buffering Data windows

Fixed and sliding windows


Buffering

A flow control technique in which data received is stored on a buffer. Is used when reading information from the disk or RAM.


Data Windows

10

1

Without data windows

With data windows

Packet

ACK

Defines how much data can be sent without waiting for an acknowledgment


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

Yes No

Request data be retransmitted


Parity Check

Compare bytes with parity bits

1 0 1 0 0 1 1 0 1 1 0 1 0 0 1 1 0 0

Parity bit Parity bit

1

Sender Receiver

Sender adds one bit to each word of data 2 Receiver compares the

transmitted and received bytes

3If there is a mismatch, the receiver requests retransmission


CRC

Cyclic Redundancy Check

Compare CRCs for error

1 0 1 1 0 1 0 0 CRC 1 0 1 1 0 1 0 0

1 Sender attaches CRC to data 2 Receiver calculates CRC for

received block

3Values match and data is unaltered


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?

ov 6 - 1 copyright © 2011 element k content llc. all rights reserved. tcp/ip addressing and data...

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