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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] |
Computer Networking
A computer network is a collection of communicating computers and other devices, such as printers and smart phones. In order to communicate, the computers and devices must be connected by wired media like copper cables, optical fibers, or by wireless communication. The devices may be connected in a variety of network topologies. In order to communicate over the network, computers use agreed-on rules, called communication protocols, over whatever medium is used. The computer network can include personal computers, Server (computing), servers, networking hardware, or other specialized or general-purpose Host (network), hosts. They are identified by network addresses and may have hostnames. Hostnames serve as memorable labels for the nodes and are rarely changed after initial assignment. Network addresses serve for locating and identifying the nodes by communication protocols such as the Internet Protocol. Computer networks may be classified by many criteria, including the tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Session Initiation Protocol
The Session Initiation Protocol (SIP) is a signaling protocol used for initiating, maintaining, and terminating communication sessions that include voice, video and messaging applications. SIP is used in Internet telephony, in private IP telephone systems, as well as mobile phone calling over LTE (telecommunication), LTE (VoLTE). The protocol defines the specific format of messages exchanged and the sequence of communications for cooperation of the participants. SIP is a text-based protocol, incorporating many elements of the Hypertext Transfer Protocol (HTTP) and the Simple Mail Transfer Protocol (SMTP). A call established with SIP may consist of multiple media streams, but no separate streams are required for applications, such as text messaging, that exchange data as payload in the SIP message. SIP works in conjunction with several other protocols that specify and carry the session media. Most commonly, media type and parameter negotiation and media setup are performed with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Port Control Protocol
Port Control Protocol (PCP) is a computer networking protocol that allows hosts on IPv4 or IPv6 networks to control how the incoming IPv4 or IPv6 packets are translated and forwarded by an upstream router that performs network address translation (NAT) or packet filtering. By allowing hosts to create explicit port forwarding rules, handling of the network traffic can be easily configured to make hosts placed behind NATs or firewalls reachable from the rest of the Internet (so they can also act as network servers), which is a requirement for many applications. Additionally, explicit port forwarding rules available through PCP allow hosts to reduce the amount of generated traffic by eliminating workarounds in form of outgoing NAT keepalive messages, which are required for maintaining connections to servers and for various NAT traversal techniques such as TCP hole punching. At the same time, less generated traffic reduces the power consumption, directly improving the battery ... [...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] |
Universal Plug And Play
Universal Plug and Play (UPnP) is a set of networking protocols on the Internet Protocol (IP) that permits networked devices, such as personal computers, printers, Internet gateways, Wi-Fi access points and mobile devices, to seamlessly discover each other's presence on the network and establish functional network services. UPnP is intended primarily for residential networks without enterprise-class devices. UPnP assumes the network runs IP, and then uses HTTP on top of IP to provide device/service description, actions, data transfer and event notification. Device search requests and advertisements are supported by running HTTP on top of UDP (port 1900) using multicast (known as HTTPMU). Responses to search requests are also sent over UDP, but are instead sent using unicast (known as HTTPU). Conceptually, UPnP extends plug and play—a technology for dynamically attaching devices directly to a computer—to zero-configuration networking for residential and SOHO wireless ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middlebox
A middlebox is a computer networking device that transforms, inspects, filters, and manipulates traffic for purposes other than packet forwarding. Examples of middleboxes include firewalls, network address translators (NATs), load balancers, and deep packet inspection (DPI) devices. The term ''middlebox'' was coined in 1999 by UCLA computer science professor Lixia Zhang. Usage Middleboxes are widely deployed across both private and public networks. Dedicated middlebox hardware is widely deployed in enterprise networks to improve network security and performance; however, even home network routers often have integrated firewall, NAT, or other middlebox functionality. One 2017 study counted more than 1,000 deployments in autonomous systems, in both directions of traffic flows, and across a wide range networks, including mobile operators and data center networks. Examples The following are examples of commonly-deployed middleboxes: * Firewalls filter traffic based on a set o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Realm-Specific IP
Realm-Specific IP was an experimental IETF framework and protocol intended as an alternative to network address translation (NAT) in which the end-to-end integrity of packets is maintained. RSIP lets a host borrow one or more IP addresses (and UDP/TCP port) from one or more RSIP gateways, by leasing (usually public) IP addresses and ports to RSIP hosts located in other (usually private) addressing realms. The RSIP client requests registration with an RSIP gateway. The gateway in turn delivers either a unique IP address or a shared IP address and a unique set of TCP/UDP ports and associates the RSIP host address to this address. The RSIP host uses this address to send packets to destinations in the other realm. The tunnelled packets between RSIP host and gateway contain both addresses, and the RSIP gateway strips off the host address header and sends the packet to the destination. RSIP can also be used to relay traffic between several different privately addressed networks by lea ... [...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] |
IP Address
An Internet Protocol address (IP address) is a numerical label such as that is assigned to a device connected to a computer network that uses the Internet Protocol for communication. IP addresses serve two main functions: network interface identification, and location addressing. Internet Protocol version 4 (IPv4) was the first standalone specification for the IP address, and has been in use since 1983. IPv4 addresses are defined as a 32-bit number, which became too small to provide enough addresses as the internet grew, leading to IPv4 address exhaustion over the 2010s. Its designated successor, IPv6, uses 128 bits for the IP address, giving it a larger address space. Although IPv6 deployment has been ongoing since the mid-2000s, both IPv4 and IPv6 are still used side-by-side . IP addresses are usually displayed in a human-readable notation, but systems may use them in various different computer number formats. CIDR notation can also be used to designate how much ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Private Network
In Internet networking, a private network is a computer network that uses a private address space of IP addresses. These addresses are commonly used for local area networks (LANs) in residential, office, and enterprise environments. Both the IPv4 and the IPv6 specifications define private IP address ranges. Most Internet service providers (ISPs) allocate only a single publicly routable IPv4 address to each residential customer, but many homes have more than one computer, smartphone, or other Internet-connected device. In this situation, a network address translator (NAT/PAT) gateway is usually used to provide Internet connectivity to multiple hosts. Private addresses are also commonly used in corporate networks which, for security reasons, are not connected directly to the Internet. Often a proxy, SOCKS gateway, or similar devices are used to provide restricted Internet access to network-internal users. Private network addresses are not allocated to any specific organizati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peer-to-peer
Peer-to-peer (P2P) computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the network, forming a peer-to-peer network of Node (networking), nodes. In addition, a personal area network (PAN) is also in nature a type of Decentralized computing, decentralized peer-to-peer network typically between two devices. Peers make a portion of their resources, such as processing power, disk storage, or network bandwidth, directly available to other network participants, without the need for central coordination by servers or stable hosts. Peers are both suppliers and consumers of resources, in contrast to the traditional client–server model in which the consumption and supply of resources are divided. While P2P systems had previously been used in many application domains, the architecture was popularized by the Internet file sharing system Napster, originally released in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
