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MPLS VPN is a family of methods for using Multiprotocol Label Switching (MPLS) to create virtual private networks (VPNs). MPLS VPN is a flexible method to transport and route several types of network traffic using an MPLS backbone.
There are three types of MPLS VPNs deployed in networks today: 1. Point-to-point (Pseudowire) 2. Layer 2 (VPLS) 3. Layer 3 (VPRN)
Point-to-point MPLS VPNs employ VLL (virtual leased lines) for providing Layer 2 point-to-point connectivity between two sites. Ethernet, TDM, and ATM frames can be encapsulated within these VLLs.
Some examples of how point-to-point VPNs might be used by utilities include:
Layer 2 MPLS VPNs, or VPLS (virtual private LAN service), offers a “switch in the cloud” style service. VPLS provides the ability to span VLANs between sites. L2 VPNs are typically used to route voice, video, and AMI traffic between substation and data center locations.
Layer 3, or VPRN (virtual private routed network), utilizes layer 3 VRF (VPN/virtual routing and forwarding) to segment routing tables for each customer utilizing the service. The customer peers with the service provider router and the two exchange routes, which are placed into a routing table specific to the customer. Multiprotocol BGP (MP-BGP) is required in the cloud to utilize the service, which increases complexity of design and implementation. L3 VPNs are typically not deployed on utility networks due to their complexity; however, a L3 VPN could be used to route traffic between corporate or datacenter locations.
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.
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 until it reaches its destination node.
A virtual private network (VPN) is a mechanism for creating a secure connection between a computing device and a computer network, or between two networks, using an insecure communication medium such as the public Internet.
A route distinguisher is an address qualifier used only within a single internet service provider's Multiprotocol Label Switching (MPLS) network. It is used to distinguish the distinct virtual private network (VPN) routes of separate customers who connect to the provider.
In computer networking and telecommunications, a pseudowire is an emulation of a point-to-point connection over a packet-switched network (PSN).
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 describing VPLS establishment.
The next-generation network (NGN) is a body of key architectural changes in telecommunication core and access networks. The general idea behind the NGN is that one network transports all information and services by encapsulating these into IP packets, similar to those used on the Internet. NGNs are commonly built around the Internet Protocol, and therefore the term all IP is also sometimes used to describe the transformation of formerly telephone-centric networks toward NGN.
In IP-based computer networks, virtual routing and forwarding (VRF) is a technology that allows multiple instances of a routing table to co-exist within the same router at the same time. One or more logical or physical interfaces may have a VRF and these VRFs do not share routes therefore the packets are only forwarded between interfaces on the same VRF. VRFs are the TCP/IP layer 3 equivalent of a VLAN. Because the routing instances are independent, the same or overlapping IP addresses can be used without conflicting with each other. Network functionality is improved because network paths can be segmented without requiring multiple routers.
A metropolitan-area Ethernet, Ethernet MAN, or metro Ethernet network is a metropolitan area network (MAN) that is based on Ethernet standards. It is commonly used to connect subscribers to a larger service network or for internet access. Businesses can also use metropolitan-area Ethernet to connect their own offices to each other.
A Layer 2 MPLS VPN is a term in computer networking. It is a method that Internet service providers use to segregate their network for their customers, to allow them to transmit data over an IP network. This is often sold as a service to businesses.
An edge device is a device that provides an entry point into enterprise or service provider core networks. Examples include routers, routing switches, integrated access devices (IADs), multiplexers, and a variety of metropolitan area network (MAN) and wide area network (WAN) access devices. Edge devices also provide connections into carrier and service provider networks. An edge device that connects a local area network to a high speed switch or backbone may be called an edge concentrator.
Virtual leased lines (VLL), also referred to as virtual private wire service (VPWS) or EoMPLS, is a way to provide Ethernet-based point to point communication over Multiprotocol Label Switching (MPLS) or Internet Protocol networks. VLL uses the pseudo-wire encapsulation for transporting Ethernet traffic over an MPLS tunnel across an MPLS backbone. VLL also describes a point to point bonded connection using the broadband bonding technology.
Provider Backbone Bridge Traffic Engineering (PBB-TE) is a computer networking technology specified in IEEE 802.1Qay, an amendment to the IEEE 802.1Q standard. PBB-TE adapts Ethernet to carrier class transport networks. It is based on the layered VLAN tags and MAC-in-MAC encapsulation defined in IEEE 802.1ah, but it differs from PBB in eliminating flooding, dynamically created forwarding tables, and spanning tree protocols. Compared to PBB and its predecessors, PBB-TE behaves more predictably and its behavior can be more easily controlled by the network operator, at the expense of requiring up-front connection configuration at each bridge along a forwarding path. PBB-TE Operations, Administration, and Management (OAM) is usually based on IEEE 802.1ag. It was initially based on Nortel's Provider Backbone Transport (PBT).
Connection-oriented Ethernet refers to the transformation of Ethernet, a connectionless communication system by design, into a connection-oriented system. The aim of connection-oriented Ethernet is to create a networking technology that combines the flexibility and cost-efficiency of Ethernet with the reliability of connection-oriented protocols. Connection-oriented Ethernet is used in commercial carrier grade networks.
A provider edge router is a router between one network service provider's area and areas administered by other network providers. A network provider is usually an Internet service provider as well.
In Multiprotocol Label Switching (MPLS), a P router or provider router is a label switch router (LSR) that functions as a transit router of the core network. The P router is typically connected to one or more PE routers.
Carrier Ethernet is a marketing term for extensions to Ethernet for communications service providers that utilize Ethernet technology in their networks.
Juniper M series is a line of multiservice edge routers designed and manufactured by Juniper Networks, for enterprise and service provider networks. It spans over M7i, M10i, M40e, M120, and M320 platforms with 5 Gbit/s up to 160 Gbit/s of full-duplex throughput. The M40 router was the first product by Juniper Networks, which was released in 1998. The M-series routers run on JUNOS Operating System.
Broadcast, unknown-unicast and multicast traffic is network traffic transmitted using one of three methods of sending data link layer network traffic to a destination of which the sender does not know the network address. This is achieved by sending the network traffic to multiple destinations on an Ethernet network. As a concept related to computer networking, it includes three types of Ethernet modes: broadcast, unicast and multicast Ethernet. BUM traffic refers to that kind of network traffic that will be forwarded to multiple destinations or that cannot be addressed to the intended destination only.
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.