IPv4 vs IPv6

Internet Protocol is a set of technical rules that define how computers communicate over a network.

There are two types of IP which are currently use they are IPv4 and IPv6. IPv6 is the new version of IPv4. 

Lets find out what is the difference between IPv4 and IPv6.

IPv4	IPv6
Source and destination addresses are 32 bits (4 bytes) in length.	Source and destination addresses are 128 bits (16 bytes) in length.
IPSec support is optional.	IPSec support is required.
IPv4 header does not identify packet flow for QoS handling by routers.	IPv6 header contains Flow Label field, which identifies packet flow for QoS handling by router.
Both routers and the sending host fragment packets.	Only the sending host fragments packets; routers do not.
Header includes a checksum.	Header does not include a checksum.
Header includes options.	All optional data is moved to IPv6 extension headers.
Address Resolution Protocol (ARP) uses broadcast ARP Request frames to resolve an IP address to a link-layer address.	Multicast Neighbor Solicitation messages resolve IP addresses to link-layer addresses.
Internet Group Management Protocol (IGMP) manages membership in local subnet groups.	Multicast Listener Discovery (MLD) messages manage membership in local subnet groups.
ICMP Router Discovery is used to determine the IPv4 address of the best default gateway, and it is optional.	ICMPv6 Router Solicitation and Router Advertisement messages are used to determine the IP address of the best default gateway, and they are required.
Broadcast addresses are used to send traffic to all nodes on a subnet.	IPv6 uses a link-local scope all-nodes multicast address.
Must be configured either manually or through DHCP.	Does not require manual configuration or DHCP.
Uses host address (A) resource records in Domain Name System (DNS) to map host names to IPv4 addresses.	Uses host address (AAAA) resource records in DNS to map host names to IPv6 addresses.
Uses pointer (PTR) resource records in the IN-ADDR.ARPA DNS domain to map IPv4 addresses to host names.	Uses pointer (PTR) resource records in the IP6.ARPA DNS domain to map IPv6 addresses to host names.
Must support a 576-byte packet size (possibly fragmented).	Must support a 1280-byte packet size (without fragmentation).

Hybrid Topology

What is a Hybrid Topology?
A combination of two or more different topologies makes for a hybrid topology. When different topologies are connected to one another, they do not display characteristics of any one specific topology. This is when it becomes a hybrid topology. It is chosen, when there are more than two basic working topologies in place already and these have to be connected to one another. When there is a star topology connected to another star topology, it still remains a star topology. However, when a star topology and bus topology are connected to one another, it gives rise to the creation of a hybrid topology. Often when the topologies are connected to one another, the layout of the resultant topology is difficult to comprehend, however, the new topology works without any problems.

Advantages
One of the prominent advantages of this topology is its flexibility. The topology is designed, so that it can be implemented for a number of different network environment. Often it is a combination of different configurations, due to which it works perfectly for different amounts of network traffic. Adding other peripheral connections is easy, as the new nodes and/or peripherals can be connected into a topology and the said topology can be connected to the hybrid topology with ease.
As compared to most other topologies, this topology is reliable. It has better fault tolerance. Since, a number of different topologies are connected to one another, in case of a problem, it becomes rather easier to isolate the different topologies connected to each other and find the fault with the hybrid topology. When a particular link in the network breaks down, it does not hamper the working of the network.
Any type of topology can be combined with another without making any changes to the existing topology. The speed of the topology is consistent, as it combines the strengths of each of the topologies and eliminates the weakness. It is also therefore, more efficient.
The most important advantage of this topology is that the weakness of the different topologies connected are neglected and only the strengths are taken into consideration. Although it makes for a very complicated topology, it is among the most effective and efficient ones.

Disadvantages
Since different topologies come together in a hybrid topology, managing the topology becomes difficult. It is also very expensive to maintain. The cost of this topology is higher as compared to the other topologies. Cost factor can be attributed to the cost of the hub, which is higher, as it has to continue to work in the network even when any one of the nodes goes down. The cost of cabling also increases, as a lot of cabling has to be carried out in this topology.
Installation and configuration of the topology is difficult. Since there are different topologies, which have to be connected to one another. At the same time, it has to be ensured that none of them fails and this makes the installation and configuration very difficult.
If there are two or more than two topologies in place, which you want to connect to one another, then it is best to opt for a hybrid topology and not worry about changing the entire topology structure.