Global Crossing Limited , was a telecommunications company that provided computer networking services and operated a tier 1 carrier . It maintained a large backbone network and offered peering , virtual private networks , leased lines, audio and video conferencing, long-distance telephone, managed services , dialup , colocation centres and VoIP . Its customer base ranged from individuals to large enterprises and other carriers, with emphasis on higher-margin layered services such as managed services and VoIP with leased lines. Its core network delivered services to more than 700 cities in more than 70 countries.
72-625: Global Crossing was the first global communications provider with IPv6 natively deployed in both its private and public networks. It was legally domiciled in Bermuda and had its administrative headquarters in New Jersey . In 1999, during the dot-com bubble , the company was valued at $ 47 billion, but it never had a profitable year. In 2002, the company filed for one of the largest bankruptcies in history and its executives were accused of covering up an accounting scandal . On October 3, 2011, Global Crossing
144-502: A link-local address , which have the prefix fe80:: / 10 . This prefix is followed by 54 bits that can be used for subnetting, although they are typically set to zeros, and a 64-bit interface identifier. The host can compute and assign the Interface identifier by itself without the presence or cooperation of an external network component like a DHCP server, in a process called link-local address autoconfiguration . The lower 64 bits of
216-507: A local area network (LAN) by sending a neighbor solicitation message asking for the link-layer address of the IP address. If any other host in the LAN is using that address, it responds. A host bringing up a new IPv6 interface first generates a unique link-local address using one of several mechanisms designed to generate a unique address. Should a non-unique address be detected, the host can try again with
288-698: A $ 1.3 billion joint venture with SoftBank Group and Microsoft to build a fiber-optic network in Asia linking Japan, China, Singapore, Hong Kong, Taiwan, South Korea, Malaysia and the Philippines. In November 1999, Global Crossing acquired Racal Telecom for $ 1.65 billion. In January 2000, the company formed a 50/50 joint venture with Hutchison Whampoa , valued at $ 1.2 billion, for a fiber-optic network in Hong Kong. In March 2000, Annunziata resigned, receiving $ 160 million during his 13-month tenure. Leo Hindery , who had joined
360-464: A 6 bit Differentiated Services Code Point and a 2-bit Explicit Congestion Notification field. Extension headers carry options that are used for special treatment of a packet in the network, e.g., for routing, fragmentation, and for security using the IPsec framework. Without special options, a payload must be less than 64 kB . With a Jumbo Payload option (in a Hop-By-Hop Options extension header),
432-615: A company from start to finish". In May 1999, Global Crossing made an offer to acquire US West , but was outbid by Qwest . In July 1999, the company acquired Global Marine Systems , the undersea cable maintenance arm of Cable & Wireless , for $ 885 million. Later that year, in September 1999, the company acquired Frontier Communications , the former Rochester Telephone Corporation , for $ 9.9 billion and renamed it Global Crossing North America. That same month, Global Crossing acquired 49% of SB Submarine Systems, and formed Asia Global Crossing,
504-861: A joint-venture company, Harbour Plaza Hotel Management to operate and manage hotels under the portfolio of the Hutchison Property division. A.S. Watson Group (ASW), HWL's retail arm, operates its flagship retail chains in Asia such as Watsons , ParknShop supermarket, TASTE food galleria , GOURMET boutique style fine food hall, GREAT Food Hall , Fortress electrical appliances store, Watson's Wine Cellar and Nuance-Watson duty-free operator. In Europe, ASW's retail network comprises health and beauty chains: DC , Drogas , Kruidvat , Rossmann , Savers Health & Beauty , Superdrug , Trekpleister [ fr ; nl ] , Spektr and Watson's , as well as luxury perfumeries and cosmetics retail brands: Marionnaud, ICI Paris XL and The Perfume Shop . A.S. Watson
576-630: A minimum set of cryptographic algorithms . This requirement will help to make IPsec implementations more interoperable between devices from different vendors. The IPsec Authentication Header (AH) and the Encapsulating Security Payload header (ESP) are implemented as IPv6 extension headers. The packet header in IPv6 is simpler than the IPv4 header. Many rarely used fields have been moved to optional header extensions. The IPv6 packet header has simplified
648-704: A mobile phone service, was launched, which became a major player in telecommunications in the 1990s. By 2004, Li's equity in Hutchison Whampoa had gradually increased to 49.9%. In March 2011, Hutchison Port Holdings Trust (HPHT) announced that the company would IPO through Singapore Exchange for about US$ 5.4 billion. This would be the largest offering in South East Asia and surpass Petronas Chemicals ' offering of about $ 4.1 billion. In January 2015, Li Ka-shing entered into talks with Telefónica to buy its British mobile division, O2 , for around $ 15.4 billion, but
720-505: A new connectivity provider with different routing prefixes is a major effort with IPv4. With IPv6, however, changing the prefix announced by a few routers can in principle renumber an entire network, since the host identifiers (the least-significant 64 bits of an address) can be independently self-configured by a host. The SLAAC address generation method is implementation-dependent. IETF recommends that addresses be deterministic but semantically opaque. Internet Protocol Security (IPsec)
792-575: A new mechanism for mapping IP addresses to link-layer addresses (e.g. MAC addresses ), because it does not support the broadcast addressing method, on which the functionality of the Address Resolution Protocol (ARP) in IPv4 is based. IPv6 implements the Neighbor Discovery Protocol (NDP, ND) in the link layer , which relies on ICMPv6 and multicast transmission. IPv6 hosts verify the uniqueness of their IPv6 addresses in
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#1732908343022864-456: A newly generated address. Once a unique link-local address is established, the IPv6 host determines whether the LAN is connected on this link to any router interface that supports IPv6. It does so by sending out an ICMPv6 router solicitation message to the all-routers multicast group with its link-local address as source. If there is no answer after a predetermined number of attempts, the host concludes that no routers are connected. If it does get
936-710: A particular privacy concern for mobile devices, such as laptops and cell phones. To address these privacy concerns, the SLAAC protocol includes what are typically called "privacy addresses" or, more correctly, "temporary addresses". Temporary addresses are random and unstable. A typical consumer device generates a new temporary address daily and will ignore traffic addressed to an old address after one week. Temporary addresses are used by default by Windows since XP SP1, macOS since (Mac OS X) 10.7, Android since 4.0, and iOS since version 4.3. Use of temporary addresses by Linux distributions varies. Renumbering an existing network for
1008-401: A response, known as a router advertisement, from a router, the response includes the network configuration information to allow establishment of a globally unique address with an appropriate unicast network prefix. There are also two flag bits that tell the host whether it should use DHCP to get further information and addresses: Hutchison Whampoa Hutchison Whampoa Limited ( HWL )
1080-478: A restructured Hutchison Whampoa to another British firm. The bank instead sold off the company on generous terms to Li Ka-shing . On 25 September 1979, at the close of trade in London , HSBC announced that it was selling its 23% stake in Hutchison Whampoa to Cheung Kong Holdings for HK$ 639 million. During the 1980s, Hutchison Whampoa bought 33% of Hong Kong Electric Holdings . In 1985, Hutchison Telecommunications ,
1152-523: A self-generated link-local address and, when connected to a network, conflict resolution is performed and routers provide network prefixes via router advertisements. Stateless configuration of routers can be achieved with a special router renumbering protocol. When necessary, hosts may configure additional stateful addresses via Dynamic Host Configuration Protocol version 6 (DHCPv6) or static addresses manually. Like IPv4, IPv6 supports globally unique IP addresses . The design of IPv6 intended to re-emphasize
1224-511: Is /22 or 1024 IPv4 addresses. A LIR may receive additional allocation when about 80% of all the address space has been utilized. RIPE NCC announced that it had fully run out of IPv4 addresses on 25 November 2019, and called for greater progress on the adoption of IPv6. On the Internet, data is transmitted in the form of network packets . IPv6 specifies a new packet format , designed to minimize packet header processing by routers. Because
1296-426: Is 1280 octets . Unlike mobile IPv4, mobile IPv6 avoids triangular routing and is therefore as efficient as native IPv6. IPv6 routers may also allow entire subnets to move to a new router connection point without renumbering. The IPv6 packet header has a minimum size of 40 octets (320 bits). Options are implemented as extensions. This provides the opportunity to extend the protocol in the future without affecting
1368-566: Is an Internet Layer protocol for packet-switched internetworking and provides end-to-end datagram transmission across multiple IP networks, closely adhering to the design principles developed in the previous version of the protocol, Internet Protocol Version 4 (IPv4). In addition to offering more addresses, IPv6 also implements features not present in IPv4. It simplifies aspects of address configuration, network renumbering, and router announcements when changing network connectivity providers. It simplifies packet processing in routers by placing
1440-617: Is defined as 0000:0000:0000:0000:0000:0000:0000:0001 and is abbreviated to ::1 by using both rules. As an IPv6 address may have more than one representation, the IETF has issued a proposed standard for representing them in text . Because IPv6 addresses contain colons, and URLs use colons to separate the host from the port number, an IPv6 address used as the host-part of a URL should be enclosed in square brackets, e.g. http://[2001:db8:4006:812::200e] or http://[2001:db8:4006:812::200e]:8080/path/page.html. All interfaces of IPv6 hosts require
1512-513: Is indicated by the Jumbo Payload Option extension header. An IPv6 packet has two parts: a header and payload . The header consists of a fixed portion with minimal functionality required for all packets and may be followed by optional extensions to implement special features. The fixed header occupies the first 40 octets (320 bits) of the IPv6 packet. It contains the source and destination addresses, traffic class, hop count, and
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#17329083430221584-485: Is its larger address space. The size of an IPv6 address is 128 bits, compared to 32 bits in IPv4. The address space therefore has 2 =340,282,366,920,938,463,463,374,607,431,768,211,456 addresses (340 undecillion , approximately 3.4 × 10 ). Some blocks of this space and some specific addresses are reserved for special uses . While this address space is very large, it was not the intent of the designers of IPv6 to assure geographical saturation with usable addresses. Rather,
1656-445: Is possible to embed the unicast address prefix into the IPv6 multicast address format, while still providing a 32-bit block, the least significant bits of the address, or approximately 4.2 billion multicast group identifiers. Thus each user of an IPv6 subnet automatically has available a set of globally routable source-specific multicast groups for multicast applications. IPv6 hosts configure themselves automatically. Every interface has
1728-526: Is slightly smaller, as multiple ranges are reserved for special usage or completely excluded from general use. The two protocols are not designed to be interoperable , and thus direct communication between them is impossible, complicating the move to IPv6. However, several transition mechanisms have been devised to rectify this. IPv6 provides other technical benefits in addition to a larger addressing space. In particular, it permits hierarchical address allocation methods that facilitate route aggregation across
1800-398: Is the world's largest health and beauty retailer. Cheung Kong Infrastructure (CKI), HWL's infrastructure arm, is a diversified infrastructure company with businesses in transportation, energy, infrastructure materials, water plants and related operations. HWL was a major shareholder of Husky Energy , one of Canada's largest energy and energy related companies, holding 33.97%. HWL owned
1872-455: Is written as four hexadecimal digits (sometimes called hextets or more formally hexadectets and informally a quibble or quad-nibble ) and the groups are separated by colons (:). An example of this representation is 2001:0db8:0000:0000:0000:ff00:0042:8329 . For convenience and clarity, the representation of an IPv6 address may be shortened with the following rules: An example of application of these rules: The loopback address
1944-552: The CIBC Argosy Merchant Funds (later Trimaran Capital Partners ). Winnick was chairman of the company from 1997 until 2002. In 1998, he hired Lodwrick Cook , former CEO of Atlantic Richfield Company , as co-chairman. John Scanlon became the first CEO of the company in the same year, but was replaced in March 1999 by Robert Annunziata, who had resigned as president of AT&T Corporation 's Business Services group to "build
2016-653: The Cayman Islands , rather than Hong Kong. In May 2015, Hutchison revealed plans to sell one-third of its stake in its British-based mobile phone businesses for a potential fee of $ 4.3 billion to five investors including GIC Private Limited , Canada Pension Plan Investment Board , Abu Dhabi Investment Authority , BTG Pactual and Caisse de dépôt et placement du Québec . HWL operated in 54 countries and employed around 230,000 staff worldwide. The company had six core businesses, most of which transferred to CK Hutchison: Hutchison Port Holdings (HPH) operates across Europe,
2088-697: The Internet Protocol . IPv4 was developed as a research project by the Defense Advanced Research Projects Agency (DARPA), a United States Department of Defense agency , before becoming the foundation for the Internet and the World Wide Web . IPv4 includes an addressing system that uses numerical identifiers consisting of 32 bits. These addresses are typically displayed in dot-decimal notation as decimal values of four octets, each in
2160-574: The Réseaux IP Européens Network Coordination Centre (RIPE NCC), Latin America and Caribbean Network Information Centre (LACNIC), and American Registry for Internet Numbers (ARIN) have reached this stage. This leaves African Network Information Center (AFRINIC) as the sole regional internet registry that is still using the normal protocol for distributing IPv4 addresses. As of November 2018, AFRINIC's minimum allocation
2232-549: The communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet . IPv6 was developed by the Internet Engineering Task Force (IETF) to deal with the long-anticipated problem of IPv4 address exhaustion , and was intended to replace IPv4 . In December 1998, IPv6 became a Draft Standard for the IETF, which subsequently ratified it as an Internet Standard on 14 July 2017. Devices on
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2304-463: The transport layer . Thus, while IPv4 allowed UDP datagram headers to have no checksum (indicated by 0 in the header field), IPv6 requires a checksum in UDP headers. IPv6 routers do not perform IP fragmentation . IPv6 hosts are required to do one of the following: perform Path MTU Discovery , perform end-to-end fragmentation, or send packets no larger than the default maximum transmission unit (MTU), which
2376-500: The " 3 " brand. It also owns 60.4% of Hutchison Asia Telecommunications (HAT), which provides mobile phone networks and data services in Asia. The company's subsidiary 3 Group Europe owns its '3' branded businesses in Europe. Another 1% of HAT is owned directly by Cheung Kong Holdings , the holding behind Cheung Kong group to which HWL belongs. Additionally, HWL is an official backer of the .mobi top level domain created specifically for
2448-596: The 1990s. Winnick salvaged $ 735 million from his $ 20 million investment, although his interest was worth $ 6 billion on paper at its peak. In April 2002, Hutchinson Whampoa bought the company's 50% interest in the Hong Kong joint venture for $ 120 million. In November 2002, Global Crossing's Asian subsidiary, Asia Global Crossing, filed bankruptcy and sold its assets to Asia Netcom, a subsidiary of China Netcom . Between 1998 and 2001, Winnick sold approximately $ 420 million in company stock and other executives sold an additional $ 900 million in company stock. On December 9, 2003,
2520-720: The Americas, Asia, the Middle East and Africa. It operates in five of the seven busiest container ports in the world, handling 13% of the world's container traffic. Hutchison Whampoa operates container terminals in Panama, as well as Mexico and other parts of the Americas. From office buildings in Hong Kong, Beijing, Shanghai, to luxury residential properties in the United Kingdom, Hutchison Whampoa Property develops and invests in real estate. Together with Cheung Kong Holdings , HWL has set up
2592-546: The IPv6 header furthers the end-to-end principle of Internet design, which envisioned that most processing in the network occurs in the leaf nodes. Integrity protection for the data that is encapsulated in the IPv6 packet is assumed to be assured by both the link layer or error detection in higher-layer protocols, namely the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP) on
2664-466: The Internet are assigned a unique IP address for identification and location definition. With the rapid growth of the Internet after commercialization in the 1990s, it became evident that far more addresses would be needed to connect devices than the IPv4 address space had available. By 1998, the IETF had formalized the successor protocol. IPv6 uses 128- bit addresses, theoretically allowing 2 , or approximately 3.4 × 10 total addresses. The actual number
2736-539: The Internet, and thus limit the expansion of routing tables . The use of multicast addressing is expanded and simplified, and provides additional optimization for the delivery of services. Device mobility, security, and configuration aspects have been considered in the design of the protocol. IPv6 addresses are represented as eight groups of four hexadecimal digits each, separated by colons. The full representation may be shortened; for example, 2001:0db8:0000:0000:0000:8a2e:0370:7334 becomes 2001:db8::8a2e:370:7334 . IPv6
2808-527: The U.S. to Japan. Despite the massive layoffs, unpaid employees, and cancelled pensions as a result of the bankruptcy, executives received huge bonuses and loan relief. In August 2000, the company was involved in an attempted rescue of a Russian submarine during the Kursk submarine disaster . Global Crossing's undersea cable division contracted with British Defense Ministry to operate the LR5 rescue submersible. As part of
2880-473: The agreement, Global Crossing was to keep it on call for emergencies. IPv6 Early research and development: Merging the networks and creating the Internet: Commercialization, privatization, broader access leads to the modern Internet: Examples of Internet services: Internet Protocol version 6 ( IPv6 ) is the most recent version of the Internet Protocol (IP),
2952-532: The company $ 650 million to use the network, a move that would boost both companies' revenues without costing them anything. The transaction did not materialize. In October 2001, Casey was replaced by John Legere , the CEO of Global Crossing subsidiary Asia Global Crossing. In the fourth quarter of 2001, the company lost $ 3.4 billion on revenue of $ 793 million. In January 2002, the company filed bankruptcy . It listed total assets of $ 22.4 billion and debts of $ 12.4 billion and
Global Crossing - Misplaced Pages Continue
3024-491: The company a few months earlier as head of its web hosting division, GlobalCenter, then became CEO. In September 2000, the company announced a deal to sell GlobalCenter to Exodus Communications for $ 6.5 billion in stock. By the time the deal closed in January 2001, the stock was only worth $ 1.95 billion. Hindery then resigned as CEO and was replaced with Thomas Casey, a lawyer who came to Global Crossing from Merrill Lynch , where he
3096-567: The company acquired Impsat, a leading Argentine telecommunications company. Global Crossing and Impsat have had a commercial relationship since 2000, when Global Crossing selected Impsat as one of its providers of Point of Presence (PoP) facilities for Global Crossing's Latin American network, known as South American Crossing. Impsat has also been a customer of Global Crossing in Latin America since 2000. In October 2011, Level 3 Communications acquired
3168-458: The company emerged from bankruptcy and on April 1, 2004, the company once again became a public company . In March 2004, Gary Winnick and other ex-executives settled lawsuits filed by investors and former employees accusing the executives of committing securities fraud by using improper accounting to inflate the company's revenue. In October 2006, the company announced the acquisition of UK-based Fibernet Corp. for £49.8 million. In May 2007,
3240-632: The company for $ 3 billion, including the assumption of $ 1.1 billion in debt. The company contributed $ 250,000 to each of the 2000 Republican National Convention and the 2000 Democratic National Convention and made major contributions to politicians of both parties. The company also courted politicians to invest in the company. The company hired lobbyist and former United States Assistant Attorney General Anne Bingaman, married to Democratic New Mexico Senator Jeff Bingaman , paying her $ 2.5 million between January and June 1999 to try to block licensing of an AT&T, MCI, and Sprint consortium to lay cable from
3312-435: The company merged with Cheung Kong Group as part of a major reorganisation of the group's businesses. The combined business was renamed CK Hutchison Holdings . Hutchison Whampoa originated as two separate companies, both founded in the 19th century. Hong Kong and Whampoa Dock was formed in 1863 by John Couper, as a port management company. Hutchison International, a wholesale trading company and importer of consumer products,
3384-408: The company, though it was later taken over by the bank. HSBC took a 22% stake in the company and replaced Clague. In 1977, Hutchison Whampoa Limited was formed as a result of merger between Hutchison International Limited and Hong Kong and Whampoa Dock Company Limited. A year later Hutchison Whampoa was listed on the stock exchange. In 1979, Michael Sandberg convinced G. M. Sayer to not hand over
3456-461: The core packet structure. However, RFC 7872 notes that some network operators drop IPv6 packets with extension headers when they traverse transit autonomous systems . IPv4 limits packets to 65,535 (2 −1) octets of payload. An IPv6 node can optionally handle packets over this limit, referred to as jumbograms , which can be as large as 4,294,967,295 (2 −1) octets. The use of jumbograms may improve performance over high- MTU links. The use of jumbograms
3528-517: The deal was blocked in 2016 by the EU's Competition Commissioner . In January 2015, Li Ka-shing confirmed plans for Cheung Kong Holdings to purchase the remaining shares in Hutchison Whampoa that it did not already own, and merge the two companies as CK Hutchison Holdings. The merger is part of a larger reorganisation of Li's businesses, which will involve the spin-off of property assets into Cheung Kong Property. The new holding company has been incorporated in
3600-418: The deployment of inter-domain solutions. In IPv4 it is very difficult for an organization to get even one globally routable multicast group assignment, and the implementation of inter-domain solutions is arcane. Unicast address assignments by a local Internet registry for IPv6 have at least a 64-bit routing prefix, yielding the smallest subnet size available in IPv6 (also 64 bits). With such an assignment it
3672-543: 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. 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
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#17329083430223744-401: The end-to-end principle of network design that was originally conceived during the establishment of the early Internet by rendering network address translation obsolete. Therefore, every device on the network is globally addressable directly from any other device. A stable, unique, globally addressable IP address would facilitate tracking a device across networks. Therefore, such addresses are
3816-538: The five regional Internet registries (RIRs). However, each RIR still has available address pools and is expected to continue with standard address allocation policies until one /8 Classless Inter-Domain Routing (CIDR) block remains. After that, only blocks of 1,024 addresses (/22) will be provided from the RIRs to a local Internet registry (LIR). As of September 2015, all of Asia-Pacific Network Information Centre (APNIC),
3888-484: The headers of IPv4 packets and IPv6 packets are significantly different, the two protocols are not interoperable. However, most transport and application-layer protocols need little or no change to operate over IPv6; exceptions are application protocols that embed Internet-layer addresses, such as File Transfer Protocol (FTP) and Network Time Protocol (NTP), where the new address format may cause conflicts with existing protocol syntax. The main advantage of IPv6 over IPv4
3960-413: The large subnet space and hierarchical route aggregation. Multicasting , the transmission of a packet to multiple destinations in a single send operation, is part of the base specification in IPv6. In IPv4 this is an optional (although commonly implemented) feature. IPv6 multicast addressing has features and protocols in common with IPv4 multicast, but also provides changes and improvements by eliminating
4032-538: The link-local address (the suffix) were originally derived from the MAC address of the underlying network interface card. As this method of assigning addresses would cause undesirable address changes when faulty network cards were replaced, and as it also suffered from a number of security and privacy issues, RFC 8064 has replaced the original MAC-based method with the hash-based method specified in RFC 7217 . IPv6 uses
4104-525: The longer addresses simplify allocation of addresses, enable efficient route aggregation , and allow implementation of special addressing features. In IPv4, complex Classless Inter-Domain Routing (CIDR) methods were developed to make the best use of the small address space. The standard size of a subnet in IPv6 is 2 addresses, about four billion times the size of the entire IPv4 address space. Thus, actual address space utilization will be small in IPv6, but network management and routing efficiency are improved by
4176-569: The mobile internet and has launched the mobile portal Three.mobi under its "3" brand. Hutchison Whampoa attempted to purchase O2 for £10.25 billion in March 2015, but the European Commission blocked the acquisition in May 2016. Hutchison Whampoa has received criticism from charities such as the Burma Campaign UK and appear on the charity's 'dirty list' for their involvement in trade with
4248-578: The need for certain protocols. IPv6 does not implement traditional IP broadcast , i.e. the transmission of a packet to all hosts on the attached link using a special broadcast address , and therefore does not define broadcast addresses. In IPv6, the same result is achieved by sending a packet to the link-local all nodes multicast group at address ff02::1, which is analogous to IPv4 multicasting to address 224.0.0.1. IPv6 also provides for new multicast implementations, including embedding rendezvous point addresses in an IPv6 multicast group address, which simplifies
4320-413: The payload must be less than 4 GB. Unlike with IPv4, routers never fragment a packet. Hosts are expected to use Path MTU Discovery to make their packets small enough to reach the destination without needing to be fragmented. See IPv6 packet fragmentation . IPv6 addresses have 128 bits. The design of the IPv6 address space implements a different design philosophy than in IPv4, in which subnetting
4392-532: The process of packet forwarding by routers . Although IPv6 packet headers are at least twice the size of IPv4 packet headers, processing of packets that only contain the base IPv6 header by routers may, in some cases, be more efficient, because less processing is required in routers due to the headers being aligned to match common word sizes . However, many devices implement IPv6 support in software (as opposed to hardware), thus resulting in very bad packet processing performance. Additionally, for many implementations,
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#17329083430224464-409: The range 0 to 255, or 8 bits per number. Thus, IPv4 provides an addressing capability of 2 or approximately 4.3 billion addresses. Address exhaustion was not initially a concern in IPv4 as this version was originally presumed to be a test of DARPA's networking concepts. During the first decade of operation of the Internet, it became apparent that methods had to be developed to conserve address space. In
4536-418: The responsibility for packet fragmentation in the end points. The IPv6 subnet size is standardized by fixing the size of the host identifier portion of an address to 64 bits. The addressing architecture of IPv6 is defined in RFC 4291 and allows three different types of transmission: unicast , anycast and multicast . Internet Protocol Version 4 (IPv4) was the first publicly used version of
4608-508: The type of the optional extension or payload which follows the header. This Next Header field tells the receiver how to interpret the data which follows the header. If the packet contains options, this field contains the option type of the next option. The "Next Header" field of the last option points to the upper-layer protocol that is carried in the packet's payload . The current use of the IPv6 Traffic Class field divides this between
4680-408: The use of Extension Headers causes packets to be processed by a router's CPU, leading to poor performance or even security issues. Moreover, an IPv6 header does not include a checksum. The IPv4 header checksum is calculated for the IPv4 header, and has to be recalculated by routers every time the time to live (called hop limit in the IPv6 protocol) is reduced by one. The absence of a checksum in
4752-459: Was acquired by Level 3 Communications for $ 3 billion, including the assumption of $ 1.1 billion in debt. In March 1997, Global Crossing was founded by Gary Winnick , the former manager of the bond desk of Drexel Burnham Lambert , and his Drexel colleagues who moved on to work at Canadian Imperial Bank of Commerce (CIBC): Abbott L. Brown, David L. Lee , and Barry Porter. In 1997, the company raised $ 35 million, including investments by Winnick and
4824-520: Was an investment holding company based in Hong Kong. It was a Fortune Global 500 company and one of the largest companies listed on the Hong Kong Stock Exchange . HWL was an international corporation with a diverse array of holdings which included the world's biggest port, and telecommunication operations in 14 countries that were run under the 3 brand. Its businesses also included retail, property development, and infrastructure. In 2015,
4896-489: Was co-head of the global telecom investment banking group. For the year 2000, the company lost $ 1.4 billion. In 2001, the company sold its local telephone operations and the Frontier name in 2001 to Frontier Communications for $ 3.65 billion in cash. In the summer of 2001, the company began discussing a transaction with Enron in which the company would pay Enron $ 650 million for its fiber-optic network in exchange for Enron paying
4968-632: Was founded in 1877 by John Duflon Hutchison. In 1965, Hutchison International under the leadership of Sir Douglas Clague gained a controlling interest of Hong Kong and Whampoa Dock . He pursued an aggressive path of diversification, acquiring A.S. Watson , Davie, Boag and Co. Ltd., Hong Kong and Whampoa Dock Co. Ltd. , and China Provident Co. Ltd. A decade later, however, the conglomerate reported losses of HK$ 130 million and became unable to service its growing debt. In 1975, Clague lost control of Hutchison Whampoa due to disastrous speculation on foreign currency and stock markets. HSBC refused to bail out
5040-571: Was originally developed for IPv6, but found widespread deployment first in IPv4, for which it was re-engineered. IPsec was a mandatory part of all IPv6 protocol implementations, and Internet Key Exchange (IKE) was recommended, but with RFC 6434 the inclusion of IPsec in IPv6 implementations was downgraded to a recommendation because it was considered impractical to require full IPsec implementation for all types of devices that may use IPv6. However, as of RFC 4301 IPv6 protocol implementations that do implement IPsec need to implement IKEv2 and need to support
5112-420: Was paying annual interest of $ 600 million. As part of the bankruptcy, Hutchison Whampoa and ST Telemedia agreed to invest $ 750 million in the company. Hutchinson Whampoa later pulled out of the deal due to regulatory resistance. CIBC realized an estimated gain of $ 2 billion from its relatively small equity investment in the company, making it one of the most profitable investments by a financial institution in
5184-666: Was used to improve the efficiency of utilization of the small address space. In IPv6, the address space is deemed large enough for the foreseeable future, and a local area subnet always uses 64 bits for the host portion of the address, designated as the interface identifier, while the most-significant 64 bits are used as the routing prefix. While the myth has existed regarding IPv6 subnets being impossible to scan, RFC 7707 notes that patterns resulting from some IPv6 address configuration techniques and algorithms allow address scanning in many real-world scenarios. The 128 bits of an IPv6 address are represented in 8 groups of 16 bits each. Each group
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