Ipv4 how many bytes

This results in enough IP addresses to connect the entire universe to the internet. Many times over! IPv6 addresses are not expressed as decimal, but as hexadecimal numbers.

Which is in fact more convenient. Expressing IPv6 addresses as decimal numbers would make then way to long. The table below shows four-bit numbers as binary, hexadecimal and decimal numbers. An IPv4 address is typically written in decimal digits, formatted as four 8-bit fields separated by periods. Each 8-bit field represents a byte of the IPv4 address. This form of representing the bytes of an IPv4 address is often referred to as the dotted-decimal format.

The bytes of the IPv4 address are further classified into two parts: the network part and the host part. The following figure shows the component parts of a typical IPv4 address, This part specifies the unique number assigned to your network.

It also identifies the class of network assigned. IPv6 multicast addresses are distinguished from unicast addresses by the value of the high-order octet of the addresses. The devices support only host-inbound and host-outbound multicast traffic. Host inbound traffic includes logging, routing protocols, management traffic, and so on.

An anycast address specifies an identifier for a set of interfaces that typically belong to different nodes. A packet with an anycast address is delivered to the nearest node, according to routing protocol rules.

There is no difference between anycast addresses and unicast addresses except for the subnet-router address. For an anycast subnet-router address, the low order bits, typically 64 or more, are zero.

Anycast addresses are taken from the unicast address space. The flow module treats anycast packets in the same way as it handles unicast packets. If an anycast packet is intended for the device, it is treated as host-inbound traffic, and it delivers it to the protocol stack which continues processing it. Unicast and multicast IPv6 addresses support address scoping, which identifies the application suitable for the address.

Link-local unicast addresses—Used only on a single network link. The first 10 bits of the prefix identify the address as a link-local address. Link-local addresses cannot be used outside the link. Site-local unicast addresses—Used only within a site or intranet. A site consists of multiple network links. Site-local addresses identify nodes inside the intranet and cannot be used outside the site. Multicast addresses support 16 different types of address scope, including node, link, site, organization, and global scope.

A 4-bit field in the prefix identifies the address scope. Unicast addresses identify a single interface. Each unicast address consists of n bits for the prefix, and — n bits for the interface ID. Multicast addresses identify a set of interfaces. Each multicast address consists of the first 8 bits of all 1s, a 4-bit flags field, a 4-bit scope field, and a bit group ID:.

The first octet of 1s identifies the address as a multicast address. The flags field identifies whether the multicast address is a well-known address or a transient multicast address.

The scope field identifies the scope of the multicast address. The bit group ID identifies the multicast group. Similar to multicast addresses, anycast addresses identify a set of interfaces. However, packets are sent to only one of the interfaces, not to all interfaces. Anycast addresses are allocated from the normal unicast address space and cannot be distinguished from a unicast address in format. Therefore, each member of an anycast group must be configured to recognize certain addresses as anycast addresses.

Addressing is the area where most of the differences between IP version 4 IPv4 and IPv6 exist, but the changes are largely about the ways in which addresses are implemented and used. IPv6 has a vastly larger address space than the impending exhausted IPv4 address space.

Each extra bit given to an address doubles the size of the address space. IPv4 has been extended using techniques such as Network Address Translation NAT , which allows for ranges of private addresses to be represented by a single public address, and temporary address assignment.

Although useful, these techniques fall short of the requirements of novel applications and environments such as emerging wireless technologies, always-on environments, and Internet-based consumer appliances. In addition to the increased address space, IPv6 addresses differ from IPv4 addresses in the following ways:. Includes a scope field that identifies the type of application that the address pertains to.

Does not support broadcast addresses, but instead uses multicast addresses to broadcast a packet. All IPv6 addresses are bits long, written as 8 sections of 16 bits each. They are expressed in hexadecimal representation, so the sections range from 0 to FFFF. Sections are delimited by colons, and leading zeroes in each section may be omitted. If two or more consecutive sections have all zeroes, they can be collapsed to a double colon.

IPv6 addresses consist of 8 groups of bit hexadecimal values separated by colons :. IPv6 addresses have the following format:. Each aaaa is a bit hexadecimal value, and each a is a 4-bit hexadecimal value. Following is a sample IPv6 address:. You can compress bit groups of zeros to double colons :: as shown in the following example, but only once per address:.

An IPv6 address prefix is a combination of an IPv6 prefix address and a prefix length.