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IPv6. IPv6 address Unicast and anycast address format. Unicast and anycast addresses are typically composed of two logical parts: a 64-bit network prefix used for routing, and a 64-bit interface identifier used to identify a host's network interface.
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IPv6 https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unicast and anycast address format • Unicast and anycast addresses are typically composed of two logical parts: a 64-bit network prefix used for routing, and a 64-bit interface identifier used to identify a host's network interface. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unicast and anycast address format • General unicast address format (routing prefix size varies) https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unicast and anycast address format • field routing prefix subnet id interface identifier https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unicast and anycast address format • The network prefix (the routing prefix combined with the subnet id) is contained in the most significant 64 bits of the address https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unicast and anycast address format • A link-local address is also based on the interface identifier, but uses a different format for the network prefix. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unicast and anycast address format • The prefix field contains the binary value 1111111010. The 54 zeroes that follow make the total network prefix the same for all link-local addresses (fe80::/64 link-local address prefix), rendering them non-routable. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Address block sizes • The size of a block of addresses is specified by writing a slash (/) followed by a number in decimal whose value is the length of the network prefix in bits, rather than by explicitly specifying which addresses are in the block. For example, an address block with 48 bits in the prefix is indicated by /48. Such a block contains 2128 − 48 = 280 addresses. The smaller the value of the network prefix, the larger the block: a /21 block is 8 times larger than a /24 block. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Special allocation • To allow for provider changes without renumbering, provider-independent address space – assigned directly to the end user by the RIRs – is taken from the special range 2001:678::/29. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Special allocation • Internet Exchange Points (IXPs) are assigned special addresses from the range 2001:7f8::/29 for communication with their connected ISPs. Root name servers have been assigned addresses from the same range. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unspecified address • The address with all zero bits is called the unspecified address (corresponding to 0.0.0.0/32 in IPv4). https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unspecified address • This address must never be assigned to an interface and is to be used only in software before the application has learned its host's source address appropriate for a pending connection. Routers must not forward packets with the unspecified address. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unspecified address • Applications may be listening on one or more specific interfaces for incoming connections, which are shown in listings of active internet connections by a specific IP address (and a port number, separated by a colon). When the unspecified address is shown it means that an application is listening for incoming connections on all available interfaces. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Default route • ::/0 — The default unicast route address (corresponding to 0.0.0.0/0 in IPv4). https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unique local addresses • Unique local address https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Unique local addresses • fc00::/7 — Unique local addresses (ULAs) are intended for local communication https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Deprecated and obsolete addresses • Further information: Historical notes https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 address Solicited-node multicast address • The least significant 24 bits of the solicited-node multicast address group ID are filled with the least significant 24 bits of the interface's unicast or anycast address. These addresses allow link-layer address resolution via Neighbor Discovery Protocol (NDP) on the link without disturbing all nodes on the local network. A host is required to join a Solicited-Node multicast group for each of its configured unicast or anycast addresses. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Hop-by-hop options and destination options • The Hop-by-Hop Options extension header needs to be examined by all nodes on the packet's path, including sending and receiving nodes. The Destination Options extension header need to be examined by the destination node(s) only. The extension headers are both at least 8 octets in size; if more options are present than will fit in that space, blocks of 8 octets are added to the header repeatedly—containing options and padding—until all options are represented. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Hop-by-hop options and destination options • Length of this header in 8-octet units, not including the first 8 octets. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Hop-by-hop options and destination options • Contains one or more options, and optional padding fields to align options and to make the total header length a multiple of 8 octets. Options are TLV-coded. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Routing • The Routing extension header is used to direct a packet to one or more intermediate nodes before being sent to its destination. The header is at least 8 octets in size; if more Type-specific Data is needed than will fit in 4 octets, blocks of 8 octets are added to the header repeatedly, until all Type-specific Data is placed. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Routing • 0 0 Next Header Hdr Ext Len Routing Type Segments Left https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Routing • The length of this header, in multiples of 8 octets, not including the first 8 octets. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Routing • Number of nodes this packet still has to visit before reaching its final destination. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Routing • Data that belongs to this type of routing header. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Fragment • In order to send a packet that is larger than the path MTU, the sending node splits the packet into fragments. The Fragment extension header carries the information necessary to reassemble the original (unfragmented) packet. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Fragment • Offset, in 8-octet units, relative to the start of the fragmentable part of the original packet. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Fragment • Packet identification value, generated by the source node. Needed for reassembly of the original packet. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Fragmenting • A packet containing a fragment of an original (larger) packet consists of two parts: the unfragmentable part of the original packet (which is the same for all fragments), and a piece of the fragmentable part of the original packet, identified by a fragment offset. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Fragmenting • The unfragmentable part of a packet consists of the fixed header and some of the extension headers of the original packet (if present): all extension headers up to and including the Routing extension header, or else the Hop-by-Hop extension header. If neither extension headers are present, the unfragmentable part is just the fixed header. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Fragmenting • The Next Header value of the last (extension) header of the unfragmentable part is set to 44 to indicate that a Fragment extension header follows. After the Fragment extension header a fragment of the rest of the original packet follows. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Fragmenting • The first fragment(s) hold the rest of the extension headers (if present). After that the rest of the payload follows. Each fragment is a multiple of 8 octets in length, except the last fragment. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Reassembly • The original packet is reassembled by the receiving node by collecting all fragments and placing each fragment at the right offset and discarding the Fragment extension headers of the packets that carried them. Packets containing fragments need not arrive in sequence; they will be rearranged by the receiving node. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Reassembly • If not all fragments are received within 60 seconds after receiving the first packet with a fragment, reassembly of the original packet is abandoned and all fragments are discarded. If the first fragment was received (which contains the fixed header), a Time Exceeded message (ICMPv6 type 3, code 1) is returned to the node originating the fragmented packet, if the packet was discarded for this reason. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 packet Reassembly • Receiving hosts must make a best-effort attempt to reassemble fragmented IP datagrams that, after reassembly, contain up to 1500 bytes https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 IPv4 • Internet Protocol Version 4 (IPv4) was the first publicly used version of the Internet Protocol https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 IPv4 • During the first decade of operation of the Internet, by the late 1980s, it became apparent that methods had to be developed to conserve address space. In the early 1990s, even after the redesign of the addressing system using a classless network model, it became clear that this would not suffice to prevent IPv4 address exhaustion, and that further changes to the Internet infrastructure were needed. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 IPv4 • The last unassigned top-level address blocks of 16 million IPv4 addresses were allocated in February 2011 by the Internet Assigned Numbers Authority (IANA) to the five regional Internet registries (RIRs) https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 subnetting reference CIDR Prefixes • |||| |||| |||| |||64 Single End-user LAN (default prefix size for SLAAC) https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 subnetting reference CIDR Prefixes • |||| |||| 36 possible future Local Internet registry extra-small allocations https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 subnetting reference CIDR Prefixes • |||| |||32 Local Internet registry minimum allocations https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
IPv6 subnetting reference CIDR Prefixes • |||| ||28 Local Internet registry medium allocations https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
Subnetwork - IPv6 subnetting • The design of the IPv6 address space differs significantly from IPv4. The primary reason for subnetting in IPv4 is to improve efficiency in the utilization of the relatively small address space available, particularly to enterprises. No such limitations exist in IPv6, as the large address space available, even to end-users, is not a limiting factor. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
Subnetwork - IPv6 subnetting • An RFC 4291 compliant subnet always uses IPv6 addresses with 64 bits for the host portion https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
Subnetwork - IPv6 subnetting • IPv6 does not implement special address formats for broadcast traffic or network numbers, and thus all addresses in a subnet are valid host addresses. The all-zeroes address is reserved as the Subnet-Router anycast address. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
Subnetwork - IPv6 subnetting • The recommended allocation for an IPv6 customer site is an address space with an 48-bit (/48) prefix. This provides 65536 subnets for a site. Despite this recommendation, other common allocations are /56 as well as /64 prefixes for a residential customer network. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
Subnetwork - IPv6 subnetting • Subnetting in IPv6 is based on the concepts of variable-length subnet masking (VLSM) and the Classless Inter-Domain Routing methodology. It is used to route traffic between the global allocation spaces and within customer networks between subnets and the Internet at large. https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
Network address translation - NAT loopback in IPv6 • Network address translation will not be commonly used in IPv6, so NAT loopback will not be commonly needed https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html
Network address translation - NAT loopback in IPv6 • Note that both the client and server must support IPv6 and IPv4 addressing in the above scenario. Also note that 2001:db8::2 is the IPv6 IP address of the server (which was 192.168.1.2 in the IPv4 example). https://store.theartofservice.com/itil-2011-foundation-complete-certification-kit-fourth-edition-study-guide-ebook-and-online-course.html