What are extension headers?

IPv6 extension headers contains supplementary information used by network devices (such as routers, switches, and endpoint hosts) to decide how to direct or process an IPv6 packet. The length of each extension header is an integer multiple of 8 octets.

What are the different types of extension headers in IPv4?

The Hop-by-Hop Extension Header is the ONLY EH that MUST be fully processed by all network devices as shown in Figure 5. From this perspective, the Hop-by-Hop EH is similar to the IPv4 options….Table 1.

Order	Header Type	Next Header Code
Upper Layer	TCP	6
Upper Layer	UDP	17
Upper Layer	ICMPv6	58

What is IPv4 header format?

IPV4 header format is 20 to 60 bytes in length. It contains information need for routing and delivery. It consists of 13 fields such as Version, Header length, total distance, identification, flags, checksum, source IP address, destination IP address. It provides essential data need to transmit the data.

What is extension in IPv6 the IPv4?

An IPv6 address is 4 times larger than IPv4, but surprisingly, the header of an IPv6 address is only 2 times larger than that of IPv4. IPv6 headers have one Fixed Header and zero or more Optional (Extension) Headers. All the necessary information that is essential for a router is kept in the Fixed Header.

Which extension headers are supported by IPv6?

The following IPv6 extension headers are currently defined.

• Routing – Extended routing, like IPv4 loose source route.
• Fragmentation – Fragmentation and reassembly.
• Authentication – Integrity and authentication, security.
• Encapsulation – Confidentiality.
• Hop-by-Hop Option – Special options that require hop-by-hop processing.

Which extension header does not include in IPv6?

Removed in IPv6. IPv6 does not include a Header Length field because the IPv6 header is always a fixed length of 40 bytes. Each extension header is either a fixed length or indicates its own length. Replaced by the IPv6 Traffic Class field.

What is IPv4 header and IPv6 header?

A packet with additional information which transmits from source to destination that uses Internet Protocol version 4 is called IPv4 header. A packet with additional information which transmits from source to destination that uses Internet Protocol version 6 is called IPv6 header.

What is IPv4 addressing?

The IPv4 address is a 32-bit number that uniquely identifies a network interface on a system, as explained in How IP Addresses Apply to Network Interfaces. An IPv4 address is written in decimal digits, divided into four 8-bit fields that are separated by periods. Each 8-bit field represents a byte of the IPv4 address.

What is the difference between IPv4 and IPv6 header?

The main difference between IPv4 and IPv6 Header is that the source and destination addresses of IPv4 header are 32 bit long while the source and destination addresses of IPv6 header are 128 bits long. A computer network is a collection of devices connected together to communicate with each other.

What are IPv6 headers?

The IPv6 header is a streamlined version of the IPv4 header. It eliminates fields that are either unneeded or rarely used, and it adds a field that provides better support for real-time traffic.

What is the length of header IPv4 and IPv6?

Header Length: The header length of 20 bytes in IPv4 whereas the header length is 40 bytes in IPv6.

What are the parts of an IPv4 address?

IPv4 addresses are 32-bit numbers that are typically displayed in dotted decimal notation and contains two primary parts: the network prefix and the host number.

How many addresses are in IPv4?

4,294,967,296 IPv4 addresses
For IPv4, this pool is 32-bits (232) in size and contains 4,294,967,296 IPv4 addresses. The IPv6 address space is 128-bits (2128) in size, containing 340,282,366,920,938,463,463,374,607,431,768,211,456 IPv6 addresses.

How long is an IPv4 header?

The IPv4 Packet Header. The general structure of the IPv4 packet is shown in Figure 7.3. The minimum header (using no options, the most common situation) has a length of 20 bytes (always shown in a 4-bytes-per-line format), and a maximum length (very rarely seen) of 60 bytes.

Does IPv6 use the same header as IPv4?

IPv6 is using two main types of headers: Main IPv6 Header and the new IPv6 Extension Headers. The main IPv6 header is equivalent to the IPv4 one with some field differences introduced for better efficiency.

How are IPv4 addresses written?

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.

What is the header size of IPv4 and IPv6?

What is IPv4 header?

IPv4 is the first major version of IP. IPv4 is a connectionless protocol for use on packet-switched networks. In this article, we will discuss about IPv4 Header. Let us discuss each field of IPv4 header one by one. 1. Version- Version is a 4 bit field that indicates the IP version used.

What is the IPv6 extension header field used for?

This field is used to either tell us about the next upper layer protocol (common) or to tell us the next IPv6 extension header. At the end of all of the extension header packets, we will have an IP packet denoting the next header as being an upper layer protocol. Here are the IPv6 extension header options (table taken from cisco.com):

How are IPv4 addresses represented?

IPv4 addresses may be represented in any notation expressing a 32-bit integer value. They are most often written in dot-decimal notation, which consists of four octets of the address expressed individually in decimal numbers and separated by periods.

What is the maximum amount of data sent in an IPv4 header?

In IPv4 header, the total length field comprises of 16 bits. Total length = Header length + Payload length. Minimum header length = 20 bytes. So, maximum amount of data that can be sent in the payload field = 2 16 – 20 bytes.