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NAT Traversal
Network address translation traversal is a computer networking technique of establishing and maintaining Internet Protocol connections across Gateway (telecommunications), gateways that implement network address translation (NAT). NAT traversal techniques are required for many network applications, such as peer-to-peer file sharing and voice over IP. Network address translation Network address translation typically uses private IP addresses on private networks with a single public IP address for the router facing the Internet. The network address translator changes the source address in network protocols for outgoing requests from that of an internal device to its external address, so that internal devices can communicate with hosts on the external network, while relaying replies back to the originating device. This leaves the internal network ill-suited for hosting services, as the NAT device has no automatic method for determining the internal host for which incoming packets fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP has the task of delivering Packet (information technology), packets from the source Host (network), host to the destination host solely based on the IP addresses in the packet Header (computing), headers. For this purpose, IP defines packet structures that encapsulation (networking), encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram with source and destination information. IP was the connectionless datagram service in the original ''Transmission Control Program'' introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NAT Port Mapping Protocol
NAT Port Mapping Protocol (NAT-PMP) is a network protocol for establishing network address translation (NAT) settings and port forwarding configurations automatically without user effort. The protocol automatically determines the external IPv4 address of a NAT gateway, and provides means for an application to communicate the parameters for communication to peers. Apple introduced NAT-PMP in 2005 by as part of the Bonjour specification, as an alternative to the more common ISO Standard Internet Gateway Device Protocol implemented in many NAT routers. The protocol was published as an informational Request for Comments (RFC) by the Internet Engineering Task Force (IETF) in RFC 6886. NAT-PMP runs over the User Datagram Protocol (UDP) and uses port number 5351 on the server, whilst port 5350 is used on the client, as per spec. It has no built-in authentication mechanisms because forwarding a port typically does not allow any activity that could not also be achieved using STUN metho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Application-level Gateway
An application-level gateway (ALG, also known as application-layer gateway, application gateway, application proxy, or application-level proxy) is a security component that augments a firewall or NAT employed in a mobile network. It allows customized NAT traversal filters to be plugged into the gateway to support address and port translation for certain application layer "control/data" protocols such as FTP, BitTorrent, SIP, RTSP, file transfer in IM applications. In order for these protocols to work through NAT or a firewall, either the application has to know about an address/port number combination that allows incoming packets, or the NAT has to monitor the control traffic and open up port mappings ('' firewall pinholes'') dynamically as required. Legitimate application data can thus be passed through the security checks of the firewall or NAT that would have otherwise restricted the traffic for not meeting its limited filter criteria. Functions An ALG may offer the foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SOCKS
A sock is a piece of clothing worn on the feet and often covering the ankle or some part of the Calf (leg), calf. Some types of shoes or boots are typically worn over socks. In ancient times, socks were made from leather or matted animal hair. In the late 16th century, machine-knit socks were first produced. Until the 1800s, both hand-made and machine-knit socks were manufactured, with the latter technique becoming more common in the 19th century, and continuing until the modern day. One of the roles of socks is absorbing perspiration. The foot is among the heaviest producers of sweat in the body, it can produce over of perspiration per day; socks help to absorb this sweat and draw it to areas where air can evaporate the perspiration. They also protect shoes, a more expensive, durable, and frequently reworn foot covering, from perspiration, extending their life. In cold environments, socks made from cotton or wool help warm up cold feet which in turn helps decrease the risk of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICMP Hole Punching
ICMP hole punching is a technique employed in network address translator (NAT) applications for maintaining Internet Control Message Protocol (ICMP) packet streams that traverse the NAT. NAT traversal techniques are typically required for client-to-client networking applications on the Internet involving hosts connected in private networks, especially in peer-to-peer and Voice over Internet Protocol (VoIP) deployments. ICMP hole punching establishes connectivity between two hosts communicating across one or more network address translators in either a peer-to-peer or client–server model. Typically, third party hosts on the public transit network are used to establish UDP or TCP port states that may be used for direct communications between the communicating hosts, however ICMP hole punching requires no third party involvement to pass information between one or more NATs by exploiting a NAT's loose acceptance of inbound ICMP Time Exceeded packets. Once an ICMP Time Exceeded pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TCP Hole Punching
TCP NAT traversal and TCP hole punching (sometimes NAT punch-through) in computer networking occurs when two hosts behind a network address translation (NAT) are trying to connect to each other with outbound TCP connections. Such a scenario is particularly important in the case of peer-to-peer communications, such as Voice-over-IP (VoIP), file sharing, teleconferencing, chat systems and similar applications. TCP hole punching is an experimentally used NAT traversal technique for establishing a TCP connection between two peers on the Internet behind NAT devices. ''NAT traversal'' is a general term for techniques that establish and maintain TCP/IP network and/or TCP connections traversing NAT gateways. Terminology In the following, the terms host, client and peer are used almost interchangeably. ; ''local endpoint'', ''internal endpoint'' : the local IP:port as seen locally by the host and the internal part of the NAT. ; ''public endpoint'', ''external endpoint'' : the externa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UDP Hole Punching
UDP hole punching is a commonly used technique employed in network address translation (NAT) applications for maintaining User Datagram Protocol (UDP) packet streams that traverse the NAT. NAT traversal techniques are typically required for client-to-client networking applications on the Internet involving hosts connected in private networks, especially in peer-to-peer, Direct Client-to-Client (DCC) and Voice over Internet Protocol (VoIP) deployments. UDP hole punching establishes connectivity between two hosts communicating across one or more network address translators. Typically, third-party hosts on the public transit network are used to establish UDP port states that may be used for direct communications between the communicating hosts. Once port state has been successfully established and the hosts are communicating, port state may be maintained either by normal communications traffic, or in the prolonged absence thereof, by keep-alive packets, usually consisting of empty UD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NAT Hole Punching
Hole punching (or sometimes punch-through) is a technique in computer networking for establishing a direct connection between two parties in which one or both are behind firewalls or behind routers that use network address translation (NAT). To punch a hole, each client connects to an unrestricted third-party server that temporarily stores external and internal address and port information for each client. The server then relays each client's information to the other, and using that information each client tries to establish direct connection; as a result of the connections using valid port numbers, restrictive firewalls or routers accept and forward the incoming packets on each side. Hole punching does not require any knowledge of the network topology to function. ICMP hole punching, UDP hole punching and TCP hole punching respectively use Internet Control Message, User Datagram and Transmission Control Protocols. Overview Networked devices with public or globally accessibl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traversal Using Relays Around NAT
Traversal Using Relays around NAT (TURN) is a protocol that assists in traversal of network address translators (NAT) or firewalls for multimedia applications. It may be used with the Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). It is most useful for clients on networks masqueraded by symmetric NAT devices. TURN does not aid in running servers on well known ports in the private network through a NAT; it supports the connection of a user behind a NAT to only a single peer, as in telephony, for example. TURN is specified by . The TURN URI scheme is documented in . Introduction Network address translation (NAT), a mechanism that serves as a measure to mitigate the issue of IPv4 address exhaustion during the transition to IPv6, is accompanied by various limitations. The most troublesome among these limitations is the fact that NAT breaks many existing IP applications, and makes it more difficult to deploy new ones. Guidelines have been developed that descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Session Traversal Utilities For NAT
STUN (Session Traversal Utilities for NAT; originally Simple Traversal of User Datagram Protocol (UDP) through Network Address Translators) is a standardized set of methods, including a network protocol, for traversal of network address translator (NAT) gateways in applications of real-time voice, video, messaging, and other interactive communications. STUN is a tool used by other protocols, such as Interactive Connectivity Establishment (ICE), the Session Initiation Protocol (SIP), and WebRTC. It provides a tool for hosts to discover the presence of a network address translator, and to discover the mapped, usually public, Internet Protocol (IP) address and port number that the NAT has allocated for the application's User Datagram Protocol (UDP) flows to remote hosts. The protocol requires assistance from a third-party network server (STUN server) located on the opposing (public) side of the NAT, usually the public Internet. STUN was first announced in RFC 3489; the title was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interactive Connectivity Establishment
Interactive Connectivity Establishment (ICE) is a technique used in computer networking to find ways for two computers to talk to each other as directly as possible in peer-to-peer networking. This is most commonly used for interactive media such as Voice over Internet Protocol (VoIP), peer-to-peer communications, video, and instant messaging. In such applications, communicating through a central server would be slow and expensive, but direct communication between client applications on the Internet is very tricky due to network address translators (NATs), firewalls, and other network barriers. ICE is developed by the Internet Engineering Task Force MMUSIC working group and is published as RFC 8445, as of August 2018, and has obsolesced both RFC 5245 and RFC 4091.RFC 4091, ''The Alternative Network Address Types (ANAT) Semantics for the Session Description Protocol (SDP) Grouping Framework'', G. Camarillo, J. Rosenberg (June 2005) Overview Network address translation (NAT) became ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small Office/home Office
Small office/home office (or single office/home office; sometimes short SOHO) refers to the category of business or cottage industry that involves from 1 to 1000 workers. In New Zealand, the Ministry of Business, Innovation and Employment (MBIE) defines a small office as 6–19 employees and a micro office as 1–5. History Before the 19th century, and the spread of the Industrial Revolution around the globe, nearly all offices were small offices and/or home offices, with only a few exceptions. Most businesses were small, and the paperwork that accompanied them was limited. The industrial revolution aggregated workers in factories, to mass-produce goods. In most circumstances, the white collar counterpart—office work—was aggregated as well in large buildings, usually in cities or densely populated suburban areas. Beginning in the mid-1980s, the advent of the personal computer and fax machine, plus breakthroughs in telecommunications, created opportunities for office worke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
