What we have used up to now(IPv4) has been used up(32 bit). With new devices adding in to the network we need a bigger address space.
So IPv6 comes with lot of extended capabilities like,
Quality of service (QoS) capabilities
NOTE
Time taken by a packet to reach the destination from the source, we call it "Delay". Variation of that delay we call as "Jitter". Jitter is dangerous much more than delay. We have to reduce it to provide QoS
In IPv6 Packet we see no of header fields
Traffic Class - This contain a number which represent the priority level this is what make QoS possible.
Flow Label - Contain a small no which is easy to handle This make routing faster and easy.
In IPv6 we find 128 bit address. There are there kinds of addresses
Uni-cast = A packet with a uni-cast address to a single interface identified by that address. ID for single interface
Any-cast = ID for group of interfaces. But packet will be delivered to the nearest one.
Multi-cast = ID for group of interfaces. Packet will go to everyone identified by that address.
NOTE
Loop back address(127.0.0.1) - Virtual address that return to same node.
Addressing model
All interfaces must have at least one link-local uni-cast address.(A single interface may have more than one ipv6 address having different type and scope)
Address representation
Can omit leading 0s at each field. But there must be one character in every field.
e.g. 23A7:00F3:0004:0000…. = 23A7:F3:4:0….
:: represent one or more groups of zeros (only once in a address).
e.g. 23:0:0:0:0:3456:A987:8 = 23::3456:A987:8
x:x:x:x:x:x:d.d.d.d, where 'x' represent 16 bit hexadecimal values and 'd' represent 8 bit values
e.g. A234:0:0:0:0:FFFF:129.144.52.38
Uses CIDR notation as in IPv4 (ipv6-address/prefix-length )
E.g. 12AB:0000:0000:CD30:0000:0000:0000:0000/60
Address type indicated by leading bits
e.g.
Loopback address - ::1
Unspecified address - :: (has no scope, cannot be assigned to any interface)
The format prefixes 001 through 111(001, 011, 101, 111 as there should be 1 at the end), except for Multicast Addresses, are all required to have to have following format.
This IEEE EUI - 64 is generated using MAC
c - company bits, m - device bits, g - global bit
IPv6 addresses with embedded IPv4 addresses
IPv4-compatible IPv6 address
IPv4-mapped IPv6 address
Hierarchical Addressing
This situation first ISP was given 200.23.16.0/20. It distribute this between 8 companies. To represent 8 companies we need 3 bits. new subnet will be 23.
IPv6 with hierarchical Addressing
Transition from IPv4 to IPv6 (rfc 2893)
Two approaches
Dual Stack approach
Tunneling approach
IPv4 (internet Protocol Version 4) 1) Header (20-60 bytes). 2) Routed Protocol. 3) Types of address: i) Unicast ii) Multicast iii) Broadcast (limited/Direct) 4) 32-bit address. 5) Address space is 2^32. 6) Format of address : Decimal dotted. 7) IP security support is optional. IPv6 (Internet Protocol Version 6) 1) Header is fixed (20 bytes). 2) ICMP6, IP 3) Types of address: i) Unicast ii) Multicast iii) Anycast 4) 128-bit address. 5) Address space is 2^128. 6) Format of address : colon hex notation. 7) IP security support is built in.
32 bits (for IPv4), or 128 bits (for IPv6).32 bits (for IPv4), or 128 bits (for IPv6).32 bits (for IPv4), or 128 bits (for IPv6).32 bits (for IPv4), or 128 bits (for IPv6).
There is no need to disable ipv4 to use ipv6.
1. Describe the main features that differentiate IPv6 from IPv4
I guess NAT64
While IPv6 is based on IPv4, it is superior. The main characteristic that shows its enhancement over IPv4 is that it processes faster.
In IPv4, the loopback address is 127.0.0.1. In IPv6 it is ::1.
There is no direct conversion.
uLol(^^,)!
IPV6 is less vulnerable to DNS Spoofing IPv4 addresses use 32 bit or 4 bytes for addressing IPv6 addresses use eight bit segments.
There are a number of technologies that can provide IPv6 translation for IPv4 users, most commonly Dual Stack and 6 to 4 tunneling. DUAL STACK involves running both IPv4 and IPv6 on a single router with the router managing the implementation of either protocol as and when necessary. 6 to 4 tunneling encapsulates an IPv6 frame in and IPv4 frame for tansport over an IPv4 network either to its destination address or a network where the IPv4 frame can be discarded.
two version IPv4 IPv6
DNS - it handles both IpV4 and IPv6 addressing.