IPv6 Features & Fundamentals

The IPv4 IP addressing has been into existing since the last 3 decades. Its availability has become scarce due its extensive usage for internet accessible devices and equipment’s. The need of IPv6 basically originates from the limitations of IPv4. The need for IPv6 is not recently evolved. This has been going on since years and has been delayed with the evolution of new technologies like NATing and subnetting.

Internet Protocol version 6 (IPv6) is the next-generation Internet Protocol version designated as the successor to IPv4. Designed in the 1970s, IPv4 was initially deployed over a network of few nodes. The 1990s saw its deployment to a large base of end-users, stretching its capabilities. It is the first experimental implementation used in the Internet and remains still predominantly in use. This current version of the Internet Protocol, IPv4, has been in use for almost 30 years (started from 1981 with RFC 791) and exhibits some challenges in supporting emerging demands for address space cardinality, high-density mobility, multimedia, and strong security.

With IPv4 addresses expected to run out in 2012, only 0.2% of Internet users still have native IPv6 connectivity. This needs to be changed soon.

On 8 June 2012 World IPv6 Day, Google along with major web companies such as Facebook and Yahoo!, enabled IPv6 on their main websites for 24 hours.

Before we move forward lets us understand how the IPv6 address is represented.

IPv6 – Address Representation

It is very important to understand how IPv6 IP addresses are structured. It is already widely known that IPv6 with its 128 bits notation is much larger than the existing IPv4 counterpart and therefore provides a larger number of IP address spaces.

The IPv6 address can be represented in the binary format as a string of 0s and 1s. A hexadecimal representation shortens the 128-bit string to 32 characters. Further, the string of 32 hexadecimal characters is segmented into 8 groups of 4 characters (or 16 bits) separated by a colon (:).

The following two additional rules were introduced to further optimize the IPv6 address representation:

The elimination of leading 0s – Within each group of 16 bits between two colons, the leading 0s can be eliminated. This means that you can write :00A1: as :A1:
The elimination of consecutive 0s – You can collapse consecutive all-0 groups of 16 bits between consecutive colons. In this case, :0000:0000:0000: becomes ::
The above rules lead to a unique compressed representation of an address. For this reason, the consecutive-0s rule can be applied only once It is important to mention that “:” is a meaningful character in the Uniform Resource Locator (URL), where it separates the port number from the address. To avoid confusion, the IPv6 address in a URL is enclosed in brackets, as shown in the following example:


More examples on IPv6 interpretation:

2031:0000:130F:0000:0000:09C0:876A:130B >>> 2031:0:130f::9c0:876a:130b

FF01:0:0:0:0:0:0:1 >>> FF01::1

0:0:0:0:0:0:0:1 >>> ::1

0:0:0:0:0:0:0:0 >>> ::

IPv6 – Address Types

Following are the three types of IPv6 addresses:

Unicast Address

The unicast address identifies a single node and as a result traffic destined to a unicast address is forwarded to only this node. For load balancing, multiple nodes can use the same address.

The following are different types of unicast addresses:

Global Unicast Addresses: These are publicly routable addresses and follow the same pattern as in IPv4.

Link-Local Addresses: These are not meant for routing and are similar to the private addresses in IPv4.They are used for on-link communication as well as link operation processes such as locating neighbors or routers.

Unique Local Addresses: These addresses are also intended for non-routing purposes, but they are nearly globally unique. Unique local addresses are designed to replace site-local addresses.

Note: Global unicast addresses are likely to coexist with other types of unicast addresses in a given interface. For example, users within an enterprise need to exchange information both within the private intranet and with resources on the Internet.


Multicast received widespread attention during the development of IPv6 when it replaced broadcast addresses in the control-plane messages, thus becoming a critical part of IPv6 network operation. The larger address space provides plenty of globally unique multicast group addresses to facilitate the deployment of multicast services. A multicast address identifies a group of interfaces. A packet with a multicast destination address is delivered to all the group members. Scoping is a powerful feature built in the IPv6 multicast address architecture. It provides routers with the information needed to contain the multicast traffic within the appropriate domain. Table 1 lists the values that are currently defined for the 4-bit scope field.

IPv6 Multicast Scopes


When the same unicast address is assigned to multiple interfaces, typically belonging to different nodes, it becomes an anycast address. Because anycast addresses are structurally indistinguishable from unicast addresses, a node has to be separately configured to understand that an address assigned to its interface is an anycast address. A packet with an anycast DA is routed to the nearest interface configured with it. An anycast address cannot be used as the SA of a packet. Anycast is currently used to virtually replicate important network resources, such as Domain Name System (DNS) root servers, web servers, and multicast rendezvous points (RPs), thus providing a level of redundancy and load sharing. IPv6 went beyond this concept in that it defined a set of reserved addresses for each unicast prefix to  facilitate the future use of anycast addresses.

IPv6 Features

IPv6 IP addressing has many features additional that are not available in the existing IPv4 addresses

The following are the enhancement features available in IPv6. These features make IPv6 IP addressing a more convenient and robust than the IPv4:

IPv6 plug and play Configuration

IPv6 supports plug and play auto configuration for its host terminals. It works with or without a DHCP server. The hosts on the link will automatically get a link-local addresses and do not need any DHCP server such as a router. While on the link the host will automatically get an IPv6 prefix, default router address, hop limit and validity lifetime of the address. The devices like routers and servers should be manually configured.

End-to-end Performance

Some latency sensitive applications don’t work well over NATing. With large number of IP addresses in IPv6 the application can be run seamless without NATing to avoid latency and performance issues.

Minimized overhead in header

Minimum overheads in the IPv6 header is one of the important factor considered during its design to ensure better and economic processing of traffic at the neighboring routers. The formatting of the IPv6 header is such that only the essential fields are placed in the header to reduce the overhead.

QoS support in IPv6

The IPv6 addressing uses a high sophisticated approach for handling high priority data packets different than the traditional best effort method used in IPv4. additional flow label fields are used for handling special traffic and there is a query done from the source to the destination to determine the possible
payload the path can handle. Accordingly the IPv6 will manage its parameters for reducing latency and minimize fragmentation. The QoS is supported in the IPSec environment as well since the special field labels are present in the header.

IPSec Security for IPv6

While IPSec was a optional security requirement for communication, it is a part of standard compliance security requirement in IPv6.

Also below is a brief comparison between both the versions –

IPv4 vs IPv6

Recommended Reading –


If the Windows operating system ever notifies you about a weak Wi-Fi signal, it probably means that your connection isn’t as fast or as reliable as it could be. Worse, you might lose your connection entirely in some parts of your home. If you want to boost the signal for your wireless network (WLAN), try some of these tips for extending your wireless range and improving your wireless network speed and performance.
1. Position your wireless router, modem router, or access point in a central location
When possible, place your wireless router, wireless modem router (a DSL or cable modem with a built-in wireless router), or wireless access point (WAP) in a central location in your home. If your wireless router, modem router, or access point is against an outside wall of your home, the signal will be weak on the other side of your home. If your router is on the first floor and your PC or laptop is on the second floor, place the router high on a shelf in the room where it is located. Don’t worry if you can’t move your wireless router, because there are many other ways to improve your connection.
2. Move the router off the floor and away from walls and metal objects (such as metal file cabinets)
Metal objects, walls, and floors will interfere with your router’s wireless signals. The closer your router is to these obstructions, the more severe the interference, and the weaker your connection will be.
3. Replace your router’s antenna
The antennas supplied with your router are designed to be omnidirectional, meaning that they broadcast in all directions around the router. If your router is near an outside wall, half of the wireless signals will be sent outside your home, and much of your router’s power will be wasted. Most routers don’t allow you to increase the power output, but you can make better use of the power. If your router’s antenna is removable, you can upgrade to a high-gain antenna that focuses the wireless signals in only one direction. You can even aim the signal in the direction you need it most.
4. Replace your laptop’s wireless PC card-based network adapter
Laptops with built-in wireless networking capability typically have excellent antennas and don’t need to have their network adapters upgraded. These tips are for laptops that do not have built-in wireless networking.
Wireless network signals must be sent both to and from your computer. Sometimes your router can broadcast strongly enough to reach your computer, but your computer can’t send signals back to your router. To improve this, replace your laptop’s PC card-based wireless network adapter with a USB wireless network adapter that uses an external antenna.
5. Add a wireless repeater
Wireless repeaters extend your wireless network range without requiring you to add any wiring. Just place the wireless repeater halfway between your wireless router, modem router, or access point and your computer, and you can get an instant boost to your wireless signal strength.
6. Change your wireless channel
Wireless routers can broadcast on several different channels, similar to the way radio stations use different channels. In the United States and Canada, these channels are 1, 6, and 11. Just as you’ll sometimes hear interference on one radio station while another is perfectly clear, sometimes one wireless channel is clearer than others. Try changing your wireless router’s channel through your router’s configuration page to see if your signal strength improves. You don’t need to change your computer’s configuration, because it can automatically detect the new channel.
7. Reduce wireless interference
The most common wireless technology, 802.11g (wireless-G), operates at a frequency of 2.4 gigahertz (GHz). Many cordless phones, microwave ovens, baby monitors, garage door openers, and other wireless electronics also use this frequency. If you use these wireless devices in your home, your computer might not be able to “hear” your router over the noise coming from them.
If your network uses wireless-G, you can quiet the noise by avoiding wireless electronics that use the 2.4 GHz frequency. Instead, look for cordless phones and other devices that use the 5.8 GHz or 900 megahertz (MHz) frequencies. Because 802.11n (wireless-N) operates at both 2.4 GHz and the less frequently used 5.0 GHz frequency, you may experience less interference on your network if you use this technology.
8. Update your firmware or your network adapter driver
Router manufacturers regularly make free improvements to their routers. Sometimes, these improvements increase performance. To get the latest firmware updates for your Cisco router, visit Cisco.com.
Similarly, network adapter vendors occasionally update the software that Windows uses to communicate with your network adapter, known as the driver. These updates typically improve performance and reliability.
9. Pick equipment from a single vendor
Although a Cisco router will work with a D-Link network adapter, you often get better performance if you pick a router and network adapter from the same vendor. Some vendors offer a performance boost of up to twice the performance when you choose their hardware (like their USB wireless network adapters).
If speeding up your connection is important to you, consider the next tip—upgrading your wireless technology.
10. Upgrade 802.11a, 802.11b, and 802.11g devices to 802.11n
Although wireless-G (802.11g) may be the most common type of wireless network, wireless-N (802.11n) is at least twice as fast and it has better range and stability. Wireless-N is backward-compatible with 802.11a, 802.11b, and 802.11g, so you can still use any existing wireless equipment that you have—though you won’t see much improvement in performance until you upgrade your computer or network adapter to wireless-G, too.
If you’re using wireless-B or wireless-G and you’re unhappy with your network’s speed and performance, consider replacing your router and network adapters with wireless-N equipment. If you’re buying new equipment, definitely choose wireless-N. Cisco Wireless-N routers, for example, are powerful, secure, and simple to set up.

Top tips for better network security

Network security has become an incredibly complicated topic. Even experienced security experts struggle to cope with the latest threats. The consequences of attacks, security breaches, non-compliance to new regulations and internet abuse have placed network security high on the boardroom agenda. To protect your valuable data and resources on network follow these simple steps
Protect your identity and information assets from spyware
Enhance spam catch rates
Enforce internet user policies
Install Firewall best practices
Deal with internal threats
Secure VPN access to the remote office/user
Protect applications
Password Protection WI-Fi should be enabled
Avoid unauthorized removebale data storage devices
Plan better security decisions to avoid disasters
Always Backup your critical data at remote location

Benefits of IPv6 its time to Adapt

With launch of IPv6, we can think of connecting everything we can imagine, but its just not about larger chunk of IP addresses. Its much more than that. World has already celebrated the World IPv6 day and its time to understand the benefits and advantages of IPv6 over IPv4 from software, hardware and even services perspective. 

  1. More Efficient Routing
    IPv6 reduces the size of routing tables and makes routing more efficient and hierarchical. IPv6 allows ISPs to aggregate the prefixes of their customers’ networks into a single prefix and announce this one prefix to the IPv6 Internet. In addition, in IPv6 networks, fragmentation is handled by the source device, rather than the router, using a protocol for discovery of the path’s maximum transmission unit (MTU).
  2. More Efficient Packet Processing
    IPv6′s simplified packet header makes packet processing more efficient. Compared with IPv4, IPv6 contains no IP-level checksum, so the checksum does not need to be recalculated at every router hop. Getting rid of the IP-level checksum was possible because most link-layer technologies already contain checksum and error-control capabilities. In addition, most transport layers, which handle end-to-end connectivity, have a checksum that enables error detection.
  3. Directed Data Flows
    IPv6 supports multicast rather than broadcast. Multicast allows bandwidth-intensive packet flows (like multimedia streams) to be sent to multiple destinations simultaneously, saving network bandwidth. Disinterested hosts no longer must process broadcast packets. In addition, the IPv6 header has a new field, named Flow Label, that can identify packets belonging to the same flow.
  4. Simplified Network Configuration
    Address auto-configuration (address assignment) is built in to IPv6. A router will send the prefix of the local link in its router advertisements. A host can generate its own IP address by appending its link-layer (MAC) address, converted into Extended Universal Identifier (EUI) 64-bit format, to the 64 bits of the local link prefix.
  5. Better Support For New Services
    By eliminating Network Address Translation (NAT), true end-to-end connectivity at the IP layer is restored, enabling new and valuable services. Peer-to-peer networks are easier to create and maintain, and services such as VoIP and Quality of Service (QoS) become more robust.
  6. More Security
    IPSec, which provides confidentiality, authentication and data integrity, is baked into in IPv6. Because of their potential to carry malware, IPv4 ICMP packets are often blocked by corporate firewalls, but ICMPv6, the implementation of the Internet Control Message Protocol for IPv6, may be permitted because IPSec can be applied to the ICMPv6 packets.

RIPE had done very hard work to help us all prepare the RFP, in order to select the appropriate devices for your network. You can find this information here.

IPv6 Migration Strategy

IPv6 is here and its no more an option.

IPv6 is enabling the new Internet, creating new opportunities for business growth. Organizations need to enable IPv6 on their networks to maintain critical connectivity with partners, customers, and employees. You can accomplish this using a phased approach that reduces disruption to your business and incorporates industry best practices and knowledge gained from successful customer deployments.

Lets have a look at the strategy which should be followed while migrating to IPv6. I found a strategy diagram on Cisco.com, to which at least I am agreeing –

Now, Lets have a look at the strategy in brief – >> Read More

What is big data?

Every day, we create 2.5 quintillion bytes of data so much that 90% of the data in the world today has been created in the last two years alone. This data comes from everywhere: sensors used to gather climate information, posts to social media sites, digital pictures and videos, purchase transaction records, and cell phone GPS signals to name a few. This data is big data.

Big data spans four dimensions: Volume, Velocity, Variety, and Veracity.

Volume: Enterprises are awash with ever-growing data of all types, easily amassing terabytes