Presented By:- Avinash Kumar Nitesh Kumar Yadav

OUTLINE  Introduction of IP v4.  Introduction of IP v6.  Advantages of IP v6 over IP v4.  Transition of IP v4 to IP v6.

 Internet Protocol version 4 (IPv4) is a 32 bit or 4 bytes address.  An IP address is separated into four octets.  Each octet is 8 bits long, resulting in a 32-bit IP address. Example: First Octet Second Octet Third Octet Fourth Octet  A computer understands an IP address in its binary form; the above address in binary would look as follows: First Octet Second Octet Third Octet Fourth Octet  Part of the above IP address identifies the network. The other part of the address identifies the host.

Subnet Mask:-  A subnet mask helps to identify network id & host id. Consider the following:  The above IP address has a subnet mask of The subnet mask follows two rules: -  If a binary bit is set to a 1 (or on) in a subnet mask, the corresponding bit in the address identifies the network.  If a binary bit is set to a 0 (or off) in a subnet mask, the corresponding bit in the address identifies the host.  Looking at the above address and subnet mask in binary: Address: Subnet Mask:  The first 16 bits of the subnet mask are set to 1. Thus, the first 16 bits of the address (158.80) identify the network. The last 16 bits of the subnet mask are set to 0. Thus, the last 16 bits of the address (164.3) identify the unique host on that network.

IP Address Classes  The IPv4 address space has been structured into several classes. The value of the first octet of an address determines the class of the network:-

Private vs Public Addresses:-  A public address can be routed on the Internet.  A private address is only intended for use within an organization, and can never be routed on the internet.  Three private addressing ranges were allocated, one for each. IPv4 class: Class A – Class B Class C Special IPv4 Addresses:- The following are special IPv4 addresses:  Known as the unspecified IPv4 address, it is used to indicate the absence of an address.  Known as the IPv4 loopback address, it is assigned to an internal loopback interface, enabling a node to send packets to itself.

 IP v6 addresses are 128 bit longer and it uses 32 hexa decimal into 8 blocks.  Each block represent 4 hexa digit and each separated by colon (:).  An hexa digit is represented as a four bits binary number. Ex:- /16 /32 /48 /64 / :A001:A101:BA10:0123:2134:178D:CBA1 Node Identifier Subnet Identifier ISP’s RIR ICANN

IPv6 Addressing:-  3FFE:80F0:0002:0000:0000:0010:0000:0000 Every 4 hex is separated by a colon ― “: “ Every 4 hex represents 16 bits or 2 bytes.  3FFE:80F0:0002:0000:0000:0010:0000:0000 3FFE:80F0:2:0:0:10:0:0 Drop leading zeros within any 16-bit chunk.

 3FFE:80F0:0002:0000:0000:0010:0000:0000 3FFE:80F0:2::10:0:0 Represent any contiguous multiple chunks of zeros into a double colon, but use only once.  3FFE:80F0:0002:0000:0000:0010:0000:0000 3FFE:80F0:2:0:0:10:: Only allowed once in address  3FFE:0000:0000:0000:0022:0000:0000:0000 3FFE::22:: 3FFE::22:0:0:0 or 3FFE:0:0:0:22:: Only allowed once in address or else it becomes ambiguous.

Advantages of IP v6 over IP v4  Larger address space :-  IPv6 increases the IP address size from 32 bits to 128 bits.  Increases number of unique IP addresses from approximately 4.3×10 9 to 3.4×  Increasing the address space to 128 bits provides the following additional potential benefits:-  Auto-configuration  Scalability of multicast routing Other Limitations of IP v 4:-  Lack of quality-of-service support.  Only an 8-bit ToS field, which is hardly used.  Problem for multimedia services.  No support for security at IP layer.  Mobility support is limited.

Transition of IP v4 to IP v6  The various transition strategies can be broadly divided into three categories:-  D ual stack,  Tunneling,  Translation. Dual-stack:-  Two TCP/IP stacks co-exists on one host.  Supporting IPv4 and IPv6.  Client uses whichever protocol it wishes. IPv4 IPv6 IPv4 TCP/UDP Application IPv6 Link ? ?

Tunneling:-  Tunneling provides a way to use an existing IPv4 routing infrastructure to carry IPv6 traffic.  Three mechanisms of tunneling are presented:  IPv6 over IPv4  IPv6 to IPv4 automatic tunneling  Tunnel Broker Tunnel Broker:-

Translation:-  The basic function of translation in IPv4/IPv6 transition is to translate IP packets.  Several translation mechanisms are based on the SIIT (Stateless IP/ICMP Translation algorithm) algorithm.  Bump-In-the-Stack Mechanism.  NAT-PT (Network Address Translation-Protocol Translation) mechanisms. Bump-In-the-Stack Mechanism:-

Network Address Translation-Protocol Translation:-  The NAT-PT mechanism is a stateful IPv4/IPv6 translator.  NAT-PT mechanism depends on ALG agents that allow an IPv6 node to communicate with an IPv4 node and vice versa for specific applications.  The NAT-PT mechanism is an interoperability solution that needs no modification or extra software, such as dual stacks, to be installed on any of the end user nodes, either the IPv4 or the IPv6 network.