Physical Layer

      The OSI model is a networking framework by implementing protocols in seven layers. The seven layers of the OSI layer are the: Physical (first layer), Data link (second layer), Network (third layer), Transport (fourth layer), Session (fifth layer), Presentation (sixth layer), Application (seventh layer). The top layer of OSI layer is the Application layer while the lowest level of the OSI layer is the Physical Layer.

      The Physical layer is the first layer of the OSI model. This layer has a mainly function of converting the bit streams. Physical layer is located below the Data Link Layer of the OSI Layer. This Physical layer has a role of transmitting bits all over the medium. Physical layer also provides a electrical , mechanical and procedural interface to a transmission medium.  Through physical layer, it also translates the logical communications from the Data Link Layer into hardware- by the means of sending and recieving data. Connector types, cable types, voltages and pin-outs are also defined as the Physical Layer.

IPv6

     What is IP address? An IP Address is represented by a binary numbers that was designed to participate in a computer network for Communication.

     Before we will discuss the IPv6 (Internet Protocol version 6) i would like to discuss first the IPv4 (Internet Protocol version 4). When we talk about IPv4 it is the fourth revision in developing Internet Protocols and also it is the first protocol version to be widely deployed. This is also a connectionless protocol for the use on  packet-switched Link Layer networks. IPv4 uses a 32-bits number addresses that means 2³² estimated to billions of possible addresses. For now due to the many users of the internet, the available IP addresses in IPv4 has going to its limit. So they came up to design IPv6. 

      
     ^{IPv6 is the newest version of the Internet Protocol that was designed to fulfill the limits beyond the IPv4. It was being defined as the new generation of an Internet Protocol (IP). It was said that IPv6 was developed by the Internet Engineering Task Force ( IETF ) and it uses a 128-bits addresses and it can supports up to} 2<sup>128 (estimated to 340 undecillion) addresses. An IPv6 has also a new packet format that was designed for minimizing packet headers processed by the routers due to the difference between IPv4 packets to IPv5 packets, the two packets are currently not interoperability. Compared to the IPv4 which it uses a 32-bits number addresses the IPv6 uses a 128-bits addresses which it has a longer availability and flexibility of IP addresses to support the new users of the internet. The IPv6 subnetting size that was being standardized by fixing the host size identifier portion of an address to 64 bits to facilitate an automatic mechanism for the host identifier from link layer media addressing information. It was said that  IPv6 has its new  added features compared to the IPv4, IPv6 can simplifies the aspects of addresses assignment , network renumbering and router announcements if changing internet connectivity providers.For now, although there are Operating Systems for this time that can now supports for the IPv6, the example of it is Linux IPv6.

      Therefore the IPv6 is a newly generation of an Internet Protocol that was designed for expanded users for the internet due to the low availability of the IPv4 IP addresses that was the first generation. Based on what I've read, the Internet Engineering Task Force ( IETF ) is continuing to study the new IPv6 to fulfill its users and in order to gain a comfortless to the users. Although, there are other Operating Systems that cannot support IPv6 but the publishers of Operating Systems supports the Internet Engineering Task Force ( IETF ) to build a new Operating Systems that will support the IPv6.</sup>