Why IPv6 and usecases
IPv6, or Internet Protocol version 6, is the successor to IPv4 (Internet Protocol version 4). IPv6 was developed to address the limitations of IPv4, primarily the exhaustion of available IPv4 addresses due to the exponential growth of the internet and connected devices. Here are some key use cases and advantages of IPv6:
1. **Address Space**: One of the primary motivations for the adoption of IPv6 is its significantly larger address space compared to IPv4. IPv6 uses 128-bit addresses, allowing for approximately 3.4×10^38 unique addresses. This vast address space ensures that there are enough addresses to accommodate the growing number of internet-connected devices, including IoT (Internet of Things) devices, mobile devices, and various other networked appliances.
2. **Address Autoconfiguration**: IPv6 includes built-in support for stateless address autoconfiguration, which simplifies network configuration for devices. With IPv6, devices can automatically generate their IPv6 addresses based on the network prefix provided by the router, eliminating the need for manual IP address assignment or DHCP (Dynamic Host Configuration Protocol) servers in many cases.
3. **Efficient Routing and Packet Processing**: IPv6 includes several improvements in routing and packet processing compared to IPv4. For example, IPv6 routers use more efficient header formats, simplified packet processing rules, and support for hierarchical addressing, leading to improved routing scalability, reduced overhead, and faster packet forwarding.
4. **Security Enhancements**: IPv6 includes built-in support for IPsec (Internet Protocol Security), which provides encryption, authentication, and integrity protection for IPv6 traffic. IPsec support in IPv6 helps enhance network security by ensuring the confidentiality and integrity of data transmitted over IPv6 networks, particularly in scenarios where end-to-end security is required.
5. **IPv6-only Networks**: As the adoption of IPv6 continues to grow, some organizations are transitioning to IPv6-only network environments. IPv6-only networks leverage the benefits of IPv6, including simplified network management, improved security, and scalability, while gradually phasing out the dependency on IPv4. However, IPv6-only deployment requires careful planning and consideration of compatibility with legacy IPv4 systems and services.
6. **Future-Proofing**: IPv6 is designed to meet the long-term addressing and scalability requirements of the internet, ensuring its viability and sustainability as the foundation of global networking infrastructure for the foreseeable future. By adopting IPv6, organizations can future-proof their networks and avoid the challenges associated with IPv4 address exhaustion and the complexities of IPv4 address sharing mechanisms (such as NAT, or Network Address Translation).
Overall, IPv6 offers numerous advantages over IPv4, including a larger address space, simplified network configuration, enhanced security features, and improved scalability. As the global transition to IPv6 continues, it is becoming increasingly essential for organizations to embrace IPv6 to ensure the continued growth and evolution of the internet.
Q. What is Internet Protocol Version 6 (IPv6)?
A. IPv6 is the next generation of the protocol that runs the Internet. IPv6 is currently a set of requests for comments (RFCs) and draft standards in the IETF. IPv6 is designed to improve upon IPv4's scalability and ease of configuration and to reintroduce the original TCP/IP benefits for global networking. These issues are central to the competitiveness and performance of all types of network-dependent businesses. Its use will also expand the capabilities of the Internet to enable a variety of valuable and exciting scenarios, including large-scale peer-to-peer and mobile applications.
Q. Is there an IPv5?
A. IPv5 was once an experimental draft proposal in the IETF defining a real-time streaming protocol. It did not result in a standard deployed on production networks. It is actually called the Internet Streaming Protocol:
Q. What applications will IPv6 enable?
A. Any application that runs on top of IPv4 can be modified to run over IPv6. However, IPv6 enables—through its effectively infinite address space—simple mass-market deployment of peer-to-peer applications and use of nontraditional Internet-connected devices.
These include consumer electronics devices such as DVD players, TVs, and digital cameras and residential IP telephony and video conferencing equipment. Some of these devices are enabled today using IPv4, though at a small scale and with significant operational and development complexity. IPv6 restores innovative freedom to the application developer at the same time it enables cost-effective support and deployment for network operators.
Q. How many addresses will IPv6 accommodate? How does that compare to IPv4?
A. IPv6 supports addresses that have four times the number of bits as those of IPv4 addresses (128 instead of 32). IPv6 is expected to accommodate, theoretically, an almost infinite number of IP addresses (3.4340,282,366,920,938,463,463,374,607,431,768,211,456).
This is four billion times four billion times four billion (2^^96) times the size of the IPv4 address space (2^^32).
In a theoretical sense this is approximately 665,570,793,348,866,943,898,599 addresses per square meter of the surface of planet
Earth (assuming Earth’s surface is 511,263,971,197,990 square meters).
In the long run, though, the focus on IPv6 is about much more than the number of individual addresses. The IPv6 address space is setup to enable many more edge networks (called subnets). To simplify configuration and plug-and-play operation models, the actual number of addresses in use will be substantially less than the theoretical maximum.
Q. Is IPv6 more secure than IPv4?
A. Because it restores the original end-to-end model of TCP/IP and has IP Security (IPSec) embedded in the core IPv6 specifications, IPv6 is often presented as being more secure than IPv4. Unfortunately, Internet security is far more complex than just IPSec support.
IPV6 Routing
Rationale for IPV6
USA is still sitting pretty
Asia and America received single class C for entire country
=current ip addresses are poorly allocated
-Agencies needing class C asked for class B
-estimates on IPv4 exhaustion largely debated
=New network devices on the rise
=NAT (our current solution) is now seen as a hindrance to innovation
=Potential future features: ipsec everywhere, mobility, simpler header
The goal is to finally eliminate NAT.
IPV6 Addressing
==============
Address size moved from 32-bit (ipv4) to 128-bit (IPv6)
Provides 340,282,366,920,938,463,463,374,607,431,770,000,000
Its a lot of address . 85% of the address space will be untouched.
To make addresses more manageable, divided into 8 groups of 4 hex characters each
2001:0050:0000:0000:0000:0AB4:1E2B:98AA
Since this is still huge so they came up with shortening processes.
Rule 1:
Eliminate groups of consecutive zeros..once
2001:0050::0AB4:1E2B:98AA
Rule2:
Drop leading zeros
2001:50::AB4:1E2B:98AA
Loopback in IPv6 is ::1
IPV6 Header (header is bigger takes more bandwidth but processing is less because of few fields compare to IPV4)
===============
ver===traffic class=== flow lable
payload length == next header == hop limit
source add (128)
destination address (128 bits)
Types of Communication and Address
=======================
Unicast : one to one
Multicast : one to many
Anycast : one to closest
Link-local scope address: layer 2 Domain
Unique/Site-local scope address : organization (eq to private ip4 address)
global scope address: internet address
But there is no unique/site address used so the ipv6 address will contain link-local and global scope.
LINK LOCAL ADDRESSES
=====================
assigned automatically as an ipv6 host comes online
similar to the 169.254.x.x addresses of IPV4
always begin with FE80 (first 10 bits : 1111 1110 10) followed by 54 bits of zeros
Last 64 bits is the 48-bit mac address with "FFEE" squeezed in the middle
Lets say mac address is : 0019.D122.DCF3
1111 1110 1000 0000 0000 .....0019.D1FF.FE22.DCF3
===================
FE80
GLOBAL ADDRESSES:
=================
Have their high-level 3 bits set to 001 (2000::/3)
Global-routing_prefix == subnet-id == interface_ID
Nbits 64-N bits 64 bits
Global routing prefix is 48 bits or less
Subnet-id is comprised of whatever bits are left over after global routing prefix
The primary addresses expected to comprise the IPv6 internet are from 2001::/16 subnet.
If we provide the subnet address, it will automatically generate the interface address
int loopback 10
ipv6 address 2001:1234:ABCD:5678::/64 eui-64 (extended unique identifier)
This will automatically generate interface id
show ipv6 int loopback 10
IPV6 Routing:
Implementing IPv6 Routing and Routing Protocols
============================================
Configuring IPv6 addressing
Things to cover:
-manual address
-link local address
-manual LL address
-ICMP ND (goodbye arp)
- multicast address
- ping
R1
::1
conf t
itn f0/0
no shut
ipv6 address 2001:11AA::1/64
show ipv6 int f0/0
R2
::2
ipv6 address 2001:11AA::2/64
no shut
show ip6 int f0/0
ping ipv6 2001:11AA::1
R1:
serial int
ipv6 address 2001
show ipv6 int br
debug ipv6 nd(neighbor discovery)
icmp neighbor discovery will be the replacement of ARP
ND process(neighbor discovery)
NS(neighbor solicitation is kind of multicast address in local network to find mac address)
After NS, receiver sends NA (neighbor advertisement) to multicast address
FF02::16 == multicast address
below addresses are automatically generated all multicast groups
FF02::1 ==all (replacement of broadcast)
FF02::2 == all routers in segment
FF02::1::FF00:2 looking last 2 address for global address
FF02::1:FFE8:0 unique link local address
new arp only bothers to whom u want to contact.
u can assign manually a link-local address or can do auto-assign
There is no arp in ipv6 instead use show ipv6 neighbor to see neighbor mac address
int f0/0
ipv6 address FE80::1:2222:3333 link-local (if you don't assign subnet mask it assumes as link-local)
Implementing IPv6 routing and routing protocols
==============================================
Static routing
===============
turn on ipv6 routing
ipv6 unicast-routing (enables ipv6 unicast routing)
ipv6 route 2001:33aa::/64 2001:22aa::2 (static route)
show ipv6 route
L == local interface
L == link local
ipv6 route ::/0 2001:11aa::1(destination address)===(default route)
traceroute ipv6 2001:11aa::2
IPv6 RIPng (next generation)
=============================
all features are same as RIP now here multicast address is FF02::9
only config is change
R1
show ipv6 route
ipv6 unicast-routing
int f0/0
ipv6 rip CCNP enable (turns on rip and send advertise on all interfaces associated with that tag, no network command here)
it use Link-local address
The above tag (CCNP) should not be same in the neighbors
debug ipv6 rip
show ipv6 protocols
here udp port used is 521
OSPFv3
=========
Everything is same except few minor diff in syntax
Diff
=========
a payload is carried over
link-local address is used for communication
enabled under the interface itself
authentication is removed
R1
ipv6 unicast-routing
int f0/0
ipv6 ospf 1 area 10
ipv6 router ospf 1
router-id 0.0.0.1
show ipv6 ospf neighbors
show ipv6 route
OI == ospf inter area routes
Transitioning to IPv6
===================================
The Migration to IPv6
Technology exists to provide a smooth, non-pressured transition
- Dual-stack routes (interfaces support both ipv4 and ipv6 connections)
- Tunneling (6 to 4 and 4 to 6) ==can create GRE or VPN tunneling
- NAT protocol translation (NAT-PT) == translation between IPv6 client and ipv4 internet and vice versa.
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