Layer 2 Tunneling Protocol
   HOME
*





Layer 2 Tunneling Protocol
In computer networking, Layer 2 Tunneling Protocol (L2TP) is a tunneling protocol used to support virtual private networks (VPNs) or as part of the delivery of services by ISPs. It uses encryption ('hiding') only for its own control messages (using an optional pre-shared secret), and does not provide any encryption or confidentiality of content by itself. Rather, it provides a tunnel for Layer 2 (which may be encrypted), and the tunnel itself may be passed over a Layer 3 encryption protocol such as IPsec. History Published in 2000 as proposed standard RFC 2661, L2TP has its origins primarily in two older tunneling protocols for point-to-point communication: Cisco's Layer 2 Forwarding Protocol (L2F) and Microsoft's Point-to-Point Tunneling Protocol (PPTP). A new version of this protocol, L2TPv3, appeared as proposed standard RFC 3931 in 2005. L2TPv3 provides additional security features, improved encapsulation, and the ability to carry data links other than simply Point-to-Point P ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Computer Network
A computer network is a set of computers sharing resources located on or provided by network nodes. The computers use common communication protocols over digital interconnections to communicate with each other. These interconnections are made up of telecommunication network technologies, based on physically wired, optical, and wireless radio-frequency methods that may be arranged in a variety of network topologies. The nodes of a computer network can include personal computers, servers, networking hardware, or other specialised or general-purpose hosts. They are identified by network addresses, and may have hostnames. Hostnames serve as memorable labels for the nodes, 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 transmission medium used to carry signals, bandwidth, communications pro ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


User Datagram Protocol
In computer networking, the User Datagram Protocol (UDP) is one of the core communication protocols of the Internet protocol suite used to send messages (transported as datagrams in packets) to other hosts on an Internet Protocol (IP) network. Within an IP network, UDP does not require prior communication to set up communication channels or data paths. UDP uses a simple connectionless communication model with a minimum of protocol mechanisms. UDP provides checksums for data integrity, and port numbers for addressing different functions at the source and destination of the datagram. It has no handshaking dialogues, and thus exposes the user's program to any unreliability of the underlying network; there is no guarantee of delivery, ordering, or duplicate protection. If error-correction facilities are needed at the network interface level, an application may instead use Transmission Control Protocol (TCP) or Stream Control Transmission Protocol (SCTP) which are designed for this ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

ADSL
Asymmetric digital subscriber line (ADSL) is a type of digital subscriber line (DSL) technology, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. ADSL differs from the less common symmetric digital subscriber line (SDSL). In ADSL, bandwidth and bit rate are said to be asymmetric, meaning greater toward the customer premises (downstream) than the reverse (upstream). Providers usually market ADSL as an Internet access service primarily for downloading content from the Internet, but not for serving content accessed by others. Overview ADSL works by using spectrum above the band used by voice telephone calls. With a DSL filter, often called ''splitter'', the frequency bands are isolated, permitting a single telephone line to be used for both ADSL service and telephone calls at the same time. ADSL is generally only installed for short distances from the telephone exchange (the las ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

PowerShell
PowerShell is a task automation and configuration management program from Microsoft, consisting of a command-line shell (computing), shell and the associated scripting language. Initially a Windows component only, known as Windows PowerShell, it was made open-source software, open-source and cross-platform on 18 August 2016 with the introduction of PowerShell Core. The former is built on the .NET Framework, the latter on .NET Core. In PowerShell, administrative tasks are generally performed via ''cmdlets'' (pronounced ''command-lets''), which are specialized .NET Class (computer programming), classes implementing a particular operation. These work by accessing data in different data stores, like the file system or Windows Registry, which are made available to PowerShell via ''providers''. Third-party developers can add cmdlets and providers to PowerShell. Cmdlets may be used by scripts, which may in turn be packaged into modules. Cmdlets work in tandem with the .NET Application pr ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Windows 10
Windows 10 is a major release of Microsoft's Windows NT operating system. It is the direct successor to Windows 8.1, which was released nearly two years earlier. It was released to manufacturing on July 15, 2015, and later to retail on July 29, 2015. Windows 10 was made available for download via MSDN and TechNet, as a free upgrade for retail copies of Windows 8 and Windows 8.1 users via the Windows Store, and to Windows 7 users via Windows Update. Windows 10 receives new builds on an ongoing basis, which are available at no additional cost to users, in addition to additional test builds of Windows 10, which are available to Windows Insiders. Devices in enterprise environments can receive these updates at a slower pace, or use long-term support milestones that only receive critical updates, such as security patches, over their ten-year lifespan of extended support. In June 2021, Microsoft announced that support for Windows 10 editions which are not in the Long-Term Se ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Netsh
In computing, netsh, or network shell, is a command-line utility included in Microsoft's Windows NT line of operating systems beginning with Windows 2000. It allows local or remote configuration of network devices such as the interface. Overview A common use of netsh is to reset the TCP/IP stack to default, known-good parameters, a task that in Windows 98 required reinstallation of the TCP/IP adapter. netsh, among many other things, also allows the user to change the IP address on their machine. Starting from Windows Vista, one can also edit wireless settings (for example, SSID) using netsh. netsh can also be used to read information from the IPv6 stack. The command netsh winsock reset can be used to reset TCP/IP problems when communicating with a networked device. References Further reading * * External links Using Netshfrom Microsoft TechNet Microsoft TechNet was a Microsoft web portal and web service for IT professionals. It included a library containing documenta ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Microsoft Management Console
Microsoft Management Console (MMC) is a component of Microsoft Windows that provides system administrators and advanced users an interface for configuring and monitoring the system. It was first introduced in 1998 with the Option Pack for Windows NT 4.0 and later came pre-bundled with Windows 2000 and its successors. Snap-ins and consoles The management console can host Component Object Model components called ''snap-ins''. Most of Microsoft's administration tools are implemented as MMC snap-ins. Third parties can also implement their own snap-ins using the MMC's application programming interfaces published on the Microsoft Developer Network's web site. Snap-ins are registered in the KEY_CLASSES_ROOT and KEY_LOCAL_MACHINE\Software\Microsoft\MMC\Snapins/code> registry keys. A snap-in combined with MMC is called a ''management saved console'', which is a file with .msc extension and can be launched using this syntax: mmc path \ filename.msc a 64 32/code>. Common snap-ins ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Windows Vista
Windows Vista is a major release of the Windows NT operating system developed by Microsoft. It was the direct successor to Windows XP, which was released five years before, at the time being the longest time span between successive releases of Microsoft Windows desktop operating systems. Software release life cycle#Release to manufacturing (RTM), Development was completed on November 8, 2006, and over the following three months, it was released in stages to computer hardware and software manufacturers, business customers and retail channels. On January 30, 2007, it was released internationally and was made available for purchase and download from the Windows Marketplace; it is the first release of Windows to be made available through a digital distribution platform. Features new to Windows Vista, New features of Windows Vista include an updated graphical user interface and Skin (computing), visual style dubbed Windows Aero, Aero, a new search component called Windows Search, red ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Windows 2000
Windows 2000 is a major release of the Windows NT operating system developed by Microsoft and oriented towards businesses. It was the direct successor to Windows NT 4.0, and was Software release life cycle#Release to manufacturing (RTM), released to manufacturing on December 15, 1999, and was officially released to retail on February 17, 2000. It was Microsoft's business operating system until the introduction of Windows XP Professional in 2001. Windows 2000 introduced NTFS 3.0, Encrypting File System, as well as basic and dynamic disk storage. Support for people with disabilities was improved over Windows NT 4.0 with a number of new Assistive technology, assistive technologies, and Microsoft increased support for different languages and Locale (computer software), locale information. The Windows 2000 Server family has additional features, most notably the introduction of Active Directory, which in the years following became a widely used directory service in business environmen ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Pre-shared Key
In cryptography, a pre-shared key (PSK) is a shared secret which was previously shared between the two parties using some secure channel before it needs to be used. Key To build a key from shared secret, the key derivation function is typically used. Such systems almost always use symmetric key cryptographic algorithms. The term PSK is used in Wi-Fi encryption such as Wired Equivalent Privacy (WEP), Wi-Fi Protected Access (WPA), where the method is called WPA-PSK or WPA2-PSK, and also in the Extensible Authentication Protocol (EAP), where it is known as EAP-PSK. In all these cases, both the wireless access points (AP) and all clients ''share'' the same key. The characteristics of this secret or key are determined by the system which uses it; some system designs require that such keys be in a particular format. It can be a password, a passphrase, or a hexadecimal string. The secret is used by all systems involved in the cryptographic processes used to secure the traffic between the ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Internet Key Exchange
In computing, Internet Key Exchange (IKE, sometimes IKEv1 or IKEv2, depending on version) is the protocol used to set up a security association (SA) in the IPsec protocol suite. IKE builds upon the Oakley protocol and ISAKMP.The Internet Key Exchange (IKE), RFC 2409, §1 Abstract IKE uses X.509 certificates for authentication ‒ either pre-shared or distributed using DNS (preferably with DNSSEC) ‒ and a Diffie–Hellman key exchange to set up a shared session secret from which cryptographic keys are derived. In addition, a security policy for every peer which will connect must be manually maintained. History The Internet Engineering Task Force (IETF) originally defined IKE in November 1998 in a series of publications (Request for Comments) known as RFC 2407, RFC 2408 and RFC 2409: * defined the Internet IP Security Domain of Interpretation for ISAKMP. * defined the Internet Security Association and Key Management Protocol (ISAKMP). * defined the Internet Key Exchange ( ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Security Association
A security association (SA) is the establishment of shared security attributes between two network entities to support secure communication. An SA may include attributes such as: cryptographic algorithm and mode; traffic encryption key; and parameters for the network data to be passed over the connection. The framework for establishing security associations is provided by the Internet Security Association and Key Management Protocol (ISAKMP). Protocols such as Internet Key Exchange (IKE) and Kerberized Internet Negotiation of Keys (KINK) provide authenticated keying material.The Internet Key Exchange (IKE), RFC 2409, §1 Abstract An SA is a simplex (one-way channel) and logical connection which endorses and provides a secure data connection between the network devices. The fundamental requirement of an SA arrives when the two entities communicate over more than one channel. Take, for example, a mobile subscriber and a base station. The subscriber may subscribe itself to more th ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]