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Ethernet VPN
Ethernet VPN (EVPN) is a technology for carrying layer 2 Ethernet traffic as a virtual private network using wide area network protocols. EVPN technologies include Ethernet over MPLS and Ethernet over VXLAN. EVPN uses encapsulation methods to ensure efficient and scalable transmission of Ethernet traffic over MPLS or IP-based networks. The Ethernet frames are encapsulated within MPLS or VXLAN headers for transport. MPLS encapsulation In MPLS-based EVPN, Ethernet frames are encapsulated with: # MPLS label stack: Each EVPN instance is associated with a unique label that helps in identifying the destination bridge domain. # Control word (optional): Provides additional information for synchronization and alignment in certain scenarios. The encapsulated packet flow includes: * Original Ethernet frame * MPLS labels * Outer IP header (in case of IP/MPLS networks) EVPNs are covered by a number of Internet RFCs, including: * * * * * References See also * Virtual Private ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethernet
Ethernet ( ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 1983 as IEEE 802.3. Ethernet has since been refined to support higher bit rates, a greater number of nodes, and longer link distances, but retains much backward compatibility. Over time, Ethernet has largely replaced competing wired LAN technologies such as Token Ring, FDDI and ARCNET. The original 10BASE5 Ethernet uses a thick coaxial cable as a shared medium. This was largely superseded by 10BASE2, which used a thinner and more flexible cable that was both less expensive and easier to use. More modern Ethernet variants use Ethernet over twisted pair, twisted pair and fiber optic links in conjunction with Network switch, switches. Over the course of its history, Ethernet data transfer rates have been increased from the original to the lates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wide Area Network
A wide area network (WAN) is a telecommunications network that extends over a large geographic area. Wide area networks are often established with leased telecommunication circuits. Businesses, as well as schools and government entities, use wide area networks to relay data to staff, students, clients, buyers and suppliers from various locations around the world. In essence, this mode of telecommunication allows a business to effectively carry out its daily function regardless of location. The Internet may be considered a WAN. Many WANs are, however, built for one particular organization and are private. WANs can be separated from local area networks (LANs) in that the latter refers to physically proximal networks. Design options The textbook definition of a WAN is a computer network spanning regions, countries, or even the world. However, in terms of the application of communication protocols and concepts, it may be best to view WANs as computer networking technologies used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPLS
Multiprotocol Label Switching (MPLS) is a routing technique in telecommunications networks that directs data from one node to the next based on labels rather than network addresses. Whereas network addresses identify endpoints, the labels identify established paths between endpoints. MPLS can encapsulate packets of various network protocols, hence the ''multiprotocol'' component of the name. MPLS supports a range of access technologies, including T1/ E1, ATM, Frame Relay, and DSL. Role and functioning In an MPLS network, labels are assigned to data packets. Packet-forwarding decisions are made solely on the contents of this label, without the need to examine the packet itself. This allows one to create end-to-end circuits across any type of transport medium, using any protocol. The primary benefit is to eliminate dependence on a particular OSI model data link layer (layer 2) technology, and eliminate the need for multiple layer-2 networks to satisfy different types of traffic. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VXLAN
Virtual eXtensible LAN (VXLAN) is a network virtualization technology that uses a VLAN-like encapsulation technique to encapsulate OSI model, OSI layer 2 Ethernet frames within layer 4 User Datagram Protocol, UDP datagrams, using 4789 as the default IANA-assigned destination UDP port number, although many implementations that predate the IANA assignment use port 8472. VXLAN attempts to address the scalability problems associated with large cloud computing deployments. VXLAN endpoints, which terminate VXLAN tunnels and may be either virtual or physical switch ports, are known as VXLAN tunnel endpoints (VTEPs). History VXLAN is an evolution of efforts to standardize on an overlay encapsulation protocol. Compared to single-tagged IEEE 802.1Q VLANs which provide a limited number of layer-2 VLANs (4094, using a 12-bit VLAN ID), VXLAN increases scalability up to about 16 million logical networks (using a 24-bit VNID) and allows for layer-2 adjacency across IP networks. Multicast or unica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Header (computing)
In information technology, header is supplemental data placed at the beginning of a block of data being stored or transmitted. In data transmission, the data following the header is sometimes called the ''Payload (computing), payload'' or ''HTML element#body, body''. It is vital that header composition follows a clear and unambiguous specification or format, to allow for parsing. Examples * E-mail header: The text (body) is preceded by header lines indicating sender, recipient, subject, sending time stamp, receiving time stamps of all intermediate and the final mail transfer agents, and much more. * Similar headers are used in Usenet (NNTP) messages, and HTTP headers. * In a data packet sent via the Internet, the data (payload) are preceded by header information such as the sender's and the recipient's IP addresses, the Communications protocol, protocol governing the format of the payload and several other formats. The header's format is specified in the Internet Protocol, see IP h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virtual Private LAN Service
Virtual Private LAN Service (VPLS) is a way to provide Ethernet-based multipoint to multipoint communication over IP or MPLS networks. It allows geographically dispersed sites to share an Ethernet broadcast domain by connecting sites through pseudowires. The term ''sites'' includes multiplicities of both servers and clients. The technologies that can be used as pseudo-wire can be Ethernet over MPLS, L2TPv3 or even GRE. There are two IETF standards-track RFCs (RFC 4761 and RFC 4762) describing VPLS establishment. VPLS is a virtual private network (VPN) technology. In contrast to L2TPv3, which allows only point-to-point layer 2 tunnels, VPLS allows any-to-any (multipoint) connectivity. In a VPLS, the local area network (LAN) at each site is extended to the edge of the provider network. The provider network then emulates a switch or bridge to connect all of the customer LANs to create a single bridged LAN. VPLS is designed for applications that require multipoint or broadcas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
