14-09-2017, 01:00 PM
Multiprotocol Label Switching (MPLS) is a type of data transport technique for high performance telecommunications networks. MPLS directs data from one network node to the next based on short path labels instead of long network addresses, avoiding complex searches in a routing table. Tags identify virtual links (paths) between distant nodes rather than endpoints. MPLS can encapsulate packets from various network protocols, hence its name "multiprotocol". MPLS supports a range of access technologies, including T1 / E1, ATM, Frame Relay and DSL.
MPLS is a scalable, protocol-independent transport. In an MPLS network, labels are assigned to data packets. Package forwarding decisions are only made on the contents of this tag, without the need to examine the package itself. This allows you to create end-to-end circuits on any type of transport medium, using any protocol. The main benefit is to eliminate the dependency of a particular OSI model data layer layer (layer 2), such as asynchronous transfer mode (ATM), Frame Relay, synchronous optical network (SONET) or Ethernet and eliminate the need multiple layers, 2 to meet different types of traffic. MPLS belongs to the packet switching family.
MPLS operates on a layer that is generally considered to be between traditional definitions of OSI Layer 2 and Layer 3 (network layer), and is therefore often referred to as a layer protocol 2.5. It was designed to provide a unified data transport service for both circuit-based clients and packet-switched clients that provide a datagram service model. It can be used to carry many different types of traffic, including IP packets, as well as native ATM, SONET, and Ethernet frames.
A number of different technologies were previously deployed with essentially identical objectives, such as Frame Relay and ATM. Frame Relay and ATM use "tags" to move frames or cells along a network. The Frame Relay frame header and ATM cell refers to the virtual circuit in which the frame or cell resides. The similarity between Frame Relay, ATM and MPLS is that at every hop across the network, the value of "tag" in the header is changed. This is different from IP packet forwarding. MPLS technologies have evolved with ATM strengths and weaknesses in mind. Many network engineers agree that ATM should be replaced by a protocol that requires less overhead, while providing connection-oriented services for variable-length frames. MPLS is replacing some of these technologies in the market. It is quite possible that MPLS will completely replace these technologies in the future, thus aligning these technologies with current and future technological needs.
MPLS dispenses the cellular switching baggage and ATM signaling protocol. MPLS recognizes that small ATM cells are not needed in the core of modern networks, since modern optical networks are so fast (from 2015, at 100 Gbit / s and more) that even 1500-byte packets of full length (the need to reduce such delays - for example, to support voice traffic) was the motivation for the cellular nature of the ATM.
MPLS is a scalable, protocol-independent transport. In an MPLS network, labels are assigned to data packets. Package forwarding decisions are only made on the contents of this tag, without the need to examine the package itself. This allows you to create end-to-end circuits on any type of transport medium, using any protocol. The main benefit is to eliminate the dependency of a particular OSI model data layer layer (layer 2), such as asynchronous transfer mode (ATM), Frame Relay, synchronous optical network (SONET) or Ethernet and eliminate the need multiple layers, 2 to meet different types of traffic. MPLS belongs to the packet switching family.
MPLS operates on a layer that is generally considered to be between traditional definitions of OSI Layer 2 and Layer 3 (network layer), and is therefore often referred to as a layer protocol 2.5. It was designed to provide a unified data transport service for both circuit-based clients and packet-switched clients that provide a datagram service model. It can be used to carry many different types of traffic, including IP packets, as well as native ATM, SONET, and Ethernet frames.
A number of different technologies were previously deployed with essentially identical objectives, such as Frame Relay and ATM. Frame Relay and ATM use "tags" to move frames or cells along a network. The Frame Relay frame header and ATM cell refers to the virtual circuit in which the frame or cell resides. The similarity between Frame Relay, ATM and MPLS is that at every hop across the network, the value of "tag" in the header is changed. This is different from IP packet forwarding. MPLS technologies have evolved with ATM strengths and weaknesses in mind. Many network engineers agree that ATM should be replaced by a protocol that requires less overhead, while providing connection-oriented services for variable-length frames. MPLS is replacing some of these technologies in the market. It is quite possible that MPLS will completely replace these technologies in the future, thus aligning these technologies with current and future technological needs.
MPLS dispenses the cellular switching baggage and ATM signaling protocol. MPLS recognizes that small ATM cells are not needed in the core of modern networks, since modern optical networks are so fast (from 2015, at 100 Gbit / s and more) that even 1500-byte packets of full length (the need to reduce such delays - for example, to support voice traffic) was the motivation for the cellular nature of the ATM.