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Foreign Agent (Mobile IP)
Mobile IP (or MIP) is an Internet Engineering Task Force (IETF) standard communications protocol that is designed to allow mobile device users to move from one network to another while maintaining a permanent IP address. Mobile IP for IPv4 is described in IETF RFC 5944, and extensions are defined in IETF RFC 4721. Mobile IPv6, the IP mobility implementation for the next generation of the Internet Protocol, IPv6, is described in RFC 6275. Introduction The Mobile IP allows for location-independent routing of IP datagrams on the Internet. Each mobile node is identified by its home address disregarding its current location in the Internet. While away from its home network, a mobile node is associated with a ''care-of'' address which identifies its current location and its home address is associated with the local endpoint of a tunnel to its ''home agent''. Mobile IP specifies how a mobile node registers with its home agent and how the home agent routes datagrams to the mobile node ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Engineering Task Force
The Internet Engineering Task Force (IETF) is a standards organization for the Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster or requirements and all its participants are volunteers. Their work is usually funded by employers or other sponsors. The IETF was initially supported by the federal government of the United States but since 1993 has operated under the auspices of the Internet Society, an international non-profit organization. Organization The IETF is organized into a large number of working groups and birds of a feather informal discussion groups, each dealing with a specific topic. The IETF operates in a bottom-up task creation mode, largely driven by these working groups. Each working group has an appointed chairperson (or sometimes several co-chairs); a charter that describes its focus; and what it is expected to produce, and when. It is open to all who want to particip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Care-of Address
A care-of address (usually referred to as ''CoA'') is a temporary IP address for a mobile device used in Internet routing. This allows a home agent to forward messages to the mobile device. A separate address is required because the IP address of the device that is used as host identification is topologically incorrect—it does not match the network of attachment. The care-of address splits the dual nature of an IP address, that is, its use is to identify the host and the location within the global IP network. Address assignment The care-of address can be acquired by the mobile node in two different ways: * ''Foreign agent care-of address'' (FACoA): The mobile node receives the same CoA as the foreign agent. All mobile nodes in the foreign network are given the same CoA. * ''Co-located care-of address'': Each mobile node in the foreign network is assigned its own CoA, usually by a DHCP server. This might happen in a network where the foreign agent has not been deployed yet. Give ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux Documentation Project
The Linux Documentation Project (LDP) is a dormant an all-volunteer project that maintains a large collection of GNU and Linux-related documentation and publishes the collection online. It began as a way for hackers to share their documentation with each other and with their users, and for users to share documentation with each other. Its documents tend to be oriented towards experienced users such as professional system administrators, but it also contains tutorials for beginners. History The LDP originally began as an FTP site in 1992, but it went on the World Wide Web at MetaLab in 1993. It is believed to have been the first Linux related website ever. Today, the LDP serves over 475 documents contributed by even more authors. About a dozen of them are book length, and most of those are available in print from major technical publishers including O'Reilly Media, O'Reilly. On 1 September 2008, LDP started a wiki to allow a better interaction with the authors and the users, wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertical Handoff
Vertical handover or vertical handoff refers to a network node changing the type of connectivity it uses to access a supporting infrastructure, usually to support node mobility. For example, a suitably equipped laptop might be able to use both a high speed wireless LAN and a cellular technology for Internet access. Wireless LAN connections generally provide higher speeds, while cellular technologies generally provide more ubiquitous coverage. Thus the laptop user might want to use a wireless LAN connection whenever one is available, and to 'fall over' to a cellular connection when the wireless LAN is unavailable. Vertical handovers refer to the automatic fallover from one technology to another in order to maintain communication. This is different from a 'horizontal handover' between different wireless access points that use the same technology in that a vertical handover involves changing the data link layer technology used to access the network. Vertical handoffs between WLAN and UM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proxy Mobile IPv6
Proxy Mobile IPv6 (or PMIPv6, or PMIP) is a network-based mobility management protocol standardized by IETF and is specified in RFC 5213. It is a protocol for building a common and access technology independent of mobile core networks, accommodating various access technologies such as WiMAX, 3GPP, 3GPP2 and WLAN based access architectures. Proxy Mobile IPv6 is the only network-based mobility management protocol standardized by IETF. Introduction Network-based mobility management enables the same functionality as Mobile IP, without any modifications to the host's TCP/IP Protocol stack. With PMIP the host can change its point-of-attachment to the Internet without changing its IP address. Contrary to Mobile IP approach, this functionality is implemented by the network, which is responsible for tracking the movements of the host and initiating the required mobility signalling on its behalf. However, in case the mobility involves different network interfaces, the host needs modification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobility Management
Mobility management is one of the major functions of a GSM or a UMTS network that allows mobile phones to work. The aim of mobility management is to track where the subscribers are, allowing calls, SMS and other mobile phone services to be delivered to them. Location update procedure A GSM or UMTS network, like all cellular networks, is basically a radio network of individual cells, known as base stations. Each base station covers a small geographical area which is part of a uniquely identified location area. By integrating the coverage of each of these base stations, a cellular network provides a radio coverage over a much wider area. For GSM, a base station is called a base transceiver station (BTS), and for UMTS it is called a Node B. A group of base stations is named a location area, or a routing area. The location update procedure allows a mobile device to inform the cellular network whenever it moves from one location area to the next. Mobiles are responsible for detecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Identifier/Locator Network Protocol
The Identifier-Locator Network Protocol (ILNP) is a network protocol that divides the two functions of network addresses, namely the identification of network endpoints, and assisting routing, by separating topological information from node identity. ILNP is backwards-compatible with existing Internet Protocol functions, and is incrementally deployable. ILNP has an architecture with two different instantiations. ILNPv4 is ILNP engineered to work as a set of IPv4 extensions, while ILNPv6 has a set of IPv6 extensions. At least three independent open-source implementations of ILNPv6 exist. University of St Andrews (Scotland) has a prototype in Linux/x86 and FreeBSD/x86, while Tsinghua U. (China) has a prototype in Linux/x86. The University of St Andrews ILNP group is led by Prof. Saleem Bhatti. Other academics involved in continuing research include Ryo Yanagida, Samuel J. Ivey and Gregor Haywood. In February 2011, the IRTF Routing Research Group (RRG) Chairs recommended that the I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Host Identity Protocol
The Host Identity Protocol (HIP) is a host identification technology for use on Internet Protocol (IP) networks, such as the Internet. The Internet has two main name spaces, IP addresses and the Domain Name System. HIP separates the end-point identifier and locator roles of IP addresses. It introduces a Host Identity (HI) name space, based on a public key security infrastructure. The Host Identity Protocol provides secure methods for IP multihoming and mobile computing. In networks that implement the Host Identity Protocol, all occurrences of IP addresses in applications are eliminated and replaced with cryptographic host identifiers. The cryptographic keys are typically, but not necessarily, self-generated. The effect of eliminating IP addresses in application and transport layers is a decoupling of the transport layer from the internetworking layer (Internet Layer) in TCP/IP.RFC 4423, ''Host Identity Protocol (HIP) Architecture'', Section 4.1 HIP was specified in the IETF HIP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GPRS Tunneling Protocol
GPRS Tunnelling Protocol (GTP) is a group of IP-based communications protocols used to carry general packet radio service (GPRS) within GSM, UMTS, LTE and 5G NR radio networks. In 3GPP architectures, GTP and Proxy Mobile IPv6 based interfaces are specified on various interface points. GTP can be decomposed into separate protocols, GTP-C, GTP-U and GTP'. GTP-C is used within the GPRS core network for signaling between gateway GPRS support nodes (GGSN) and serving GPRS support nodes (SGSN). This allows the SGSN to activate a session on a user's behalf (PDP context activation), to deactivate the same session, to adjust quality of service parameters, or to update a session for a subscriber who has just arrived from another SGSN. GTP-U is used for carrying user data within the GPRS core network and between the radio access network and the core network. The user data transported can be packets in any of IPv4, IPv6, or PPP formats. GTP' (''GTP prime'') uses the same message st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Router (computing)
A router is a networking device that forwards data packets between computer networks. Routers perform the traffic directing functions between networks and on the global Internet. Data sent through a network, such as a web page or email, is in the form of data packets. A packet is typically forwarded from one router to another router through the networks that constitute an internetwork (e.g. the Internet) until it reaches its destination node. A router is connected to two or more data lines from different IP networks. When a data packet comes in on one of the lines, the router reads the network address information in the packet header to determine the ultimate destination. Then, using information in its routing table or routing policy, it directs the packet to the next network on its journey. The most familiar type of IP routers are home and small office routers that simply forward IP packets between the home computers and the Internet. More sophisticated routers, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triangular Routing
Triangular routing is a method for transmitting packets of data in communications networks. It uses a form of routing that sends a packet to a proxy system before transmission to the intended destination. Triangular routing is a problem in mobile IP; however, it finds applications in other networking situations, for instance to avoid problems associated with network address translation (NAT), implemented for example by Skype. 2) Datagram is intercepted 3) Datagram is by home agent and detunneled and is tunneled to the delivered to the care-of address. mobile node. +-----+ +-------+ +------+ , home , > , foreign, ------> , mobile, , agent, , agent , <------ , node , +-----+ +-------+ +------+ 1) Datagram to /, \ / mobile n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IP Tunnel
An IP tunnel is an Internet Protocol (IP) network communications channel between two networks. It is used to transport another network protocol by encapsulation of its packets. IP tunnels are often used for connecting two disjoint IP networks that don't have a native routing path to each other, via an underlying routable protocol across an intermediate transport network. In conjunction with the IPsec protocol they may be used to create a virtual private network between two or more private networks across a public network such as the Internet. Another prominent use is to connect islands of IPv6 installations across the IPv4 Internet. In IP tunnelling, every IP packet, including addressing information of its source and destination IP networks, is encapsulated within another packet format native to the transit network. At the borders between the source network and the transit network, as well as the transit network and the destination network, gateways are used that establish t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
