750:, require keeping a label even between the penultimate and the last MPLS router, with a label disposition always done on the last MPLS router, ultimate hop popping (UHP). Some specific label values have been notably reserved for this use. In this scenario the remaining label stack entry conveys information to the last hop (such as its Traffic Class field for QoS information), while also instructing the last hop to pop the label stack using one of the following reserved label values:
739:(PHP). This is useful in cases where the egress router has many packets leaving MPLS tunnels and thus spends significant CPU resources on these transitions. By using PHP, transit routers connected directly to this egress router effectively offload it, by popping the last label themselves. In the label distribution protocols, this PHP label pop action is advertised as label value 3 (implicit null) and is never found in a label, since it means that the label is to be popped.
812:
Note that LSPs are unidirectional; they enable a packet to be label switched through the MPLS network from one endpoint to another. Since bidirectional communication is typically desired, the aforementioned dynamic signaling protocols can automatically set up a separate LSP in the opposite direction.
298:
and in forwarding algorithms have made hardware forwarding of IP packets possible and common. The current advantages of MPLS primarily revolve around the ability to support multiple service models and perform traffic management. MPLS also offers a robust recovery framework that goes beyond the simple
92:
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
1017:
The most significant difference is in the transport and encapsulation methods. MPLS is able to work with variable-length packets while ATM uses fixed-length (53 bytes) cells. Packets must be segmented, transported and re-assembled over an ATM network using an adaptation layer, which adds significant
731:
At the egress router, when the last label has been popped, only the payload remains. This can be an IP packet or any type of packet. The egress router must, therefore, have routing information for the packet's payload since it must forward it without the help of label lookup tables. An MPLS transit
572:
into the MPLS domain, a LER uses routing information to determine the appropriate label to be affixed, labels the packet accordingly, and then forwards the labeled packet into the MPLS domain. Likewise, upon receiving a labeled packet that is destined to exit the MPLS domain, the LER strips off the
1021:
Differences exist, as well, in the nature of the connections. An MPLS connection (LSP) is unidirectional, allowing data to flow in only one direction between two endpoints. Establishing two-way communications between endpoints requires a pair of LSPs be established. Because two LSPs are used, data
723:
During these operations, the contents of the packet below the MPLS Label stack are not examined. Indeed, transit routers typically need only to examine the topmost label on the stack. The forwarding of the packet is done based on the contents of the labels, which allows protocol-independent packet
1009:
provide a connection-oriented service for transporting data across computer networks. In both technologies, connections are signaled between endpoints, the connection state is maintained at each node in the path, and encapsulation techniques are used to carry data across the connection. Excluding
793:
The path begins at an LER, which makes a decision on which label to prefix to a packet based on the appropriate FEC. It then forwards the packet along to the next router in the path, which swaps the packet's outer label for another label, and forwards it to the next router. The last router in the
898:
In a pure IP network, the shortest path to a destination is chosen even when the path becomes congested. Meanwhile, in an IP network with MPLS Traffic
Engineering CSPF routing, constraints such as the RSVP bandwidth of the traversed links can also be considered, such that the shortest path with
174:
for variable-length frames, and has replaced much use of ATM in the market. MPLS dispenses with the cell-switching and signaling-protocol baggage of ATM. MPLS recognizes that small ATM cells are not needed in the core of modern networks, since modern optical networks are fast enough that even
761:
An MPLS header does not identify the type of data carried inside the MPLS path. To carry two different types of traffic between the same two routers, with different treatment by the core routers for each type, a separate MPLS path for each type of traffic is required.
625:
Label-switched paths (LSPs) are established by the network operator for a variety of purposes, such as to create network-based IP virtual private networks or to route traffic along specified paths through the network. In many respects, LSPs are not different from
617:(RSVP). LSRs in an MPLS network regularly exchange label and reachability information with each other using standardized procedures in order to build a complete picture of the network so that they can then use that information to forward the packets.
907:(IS-IS) and RSVP. In addition to the constraint of RSVP bandwidth, users can also define their own constraints by specifying link attributes and special requirements for tunnels to route (or not to route) over links with certain attributes.
1036:
The biggest advantage that MPLS has over ATM is that it was designed from the start to be complementary to IP. Modern routers can support both MPLS and IP natively across a common interface allowing network operators great flexibility in
1122:-based switching able to forward plain IPv4 as fast as MPLS labeled packets. Now, therefore, the main benefit of MPLS is to implement limited traffic engineering and layer 3 or layer 2 service provider type VPNs over IPv4 networks.
676:
operation is performed on the packet's label stack. Routers can have prebuilt lookup tables that tell them which kind of operation to do based on the topmost label of the incoming packet so they can process the packet very quickly.
1033:. MPLS can stack multiple labels to form tunnels within tunnels. The ATM virtual path indicator (VPI) and virtual circuit indicator (VCI) are both carried together in the cell header, limiting ATM to a single level of tunneling.
289:
Some time later it was recognized that the work on threaded indices by Girish
Chandranmenon and George Varghese had invented the idea of using labels to represent destination prefixes that was central to tag switching.
286:(IETF) for open standardization. The IETF formed the MPLS Working Group in 1997. Work involved proposals from other vendors, and development of a consensus protocol that combined features from several vendors' work.
1109:
environment, using appropriate routing protocols. The major goal of MPLS development was the increase of routing speed. This goal is no longer relevant because of the usage of newer switching methods such as
293:
One original motivation was to allow the creation of simple high-speed switches since for a significant length of time it was considered impractical to forward IP packets entirely in hardware. Advances in
875:(IGPs). MPLS LSPs provide dynamic, transparent virtual networks with support for traffic engineering, the ability to transport layer-3 (IP) VPNs with overlapping address spaces, and support for layer-2
944:
In the event of a network element failure when recovery mechanisms are employed at the IP layer, restoration may take several seconds which may be unacceptable for real-time applications such as
891:, ATM, Frame Relay, etc.). MPLS-capable devices are referred to as LSRs. The paths an LSR knows can be defined using explicit hop-by-hop configuration, or are dynamically routed by the
1022:
flowing in the forward direction may use a different path from data flowing in the reverse direction. ATM point-to-point connections (virtual circuits), on the other hand, are
997:
Many customers migrated from Frame Relay to MPLS over IP or
Ethernet, which in many cases reduced costs and improved manageability and performance of their wide area networks.
968:
MPLS can make use of existing ATM network or Frame Relay infrastructure, as its labeled flows can be mapped to ATM or Frame Relay virtual-circuit identifiers, and vice versa.
2060:
Proceedings IEEE INFOCOM 2001. Conference on
Computer Communications. Twentieth Annual Joint Conference of the IEEE Computer and Communications Society (Cat. No.01CH37213)
646:(FEC) for the packet and then inserts one or more labels in the packet's newly created MPLS header. The packet is then passed on to the next hop router for this tunnel.
100:(layer 2) technology, and eliminate the need for multiple layer-2 networks to satisfy different types of traffic. Multiprotocol label switching belongs to the family of
2283:
2128:
1723:
1082:
193:
1041:
and operation. ATM's incompatibilities with IP require complex adaptation, making it comparatively less suitable for today's predominantly IP networks.
1666:
1585:
1018:
complexity and overhead to the data stream. MPLS, on the other hand, simply adds a label to the head of each packet and transmits it on the network.
1078:
170:. MPLS technologies have evolved with the strengths and weaknesses of ATM in mind. MPLS is designed to have lower overhead than ATM while providing
553:(LER, also known as edge LSR) is a router that operates at the edge of an MPLS network and acts as the entry and exit points for the network. LERs
150:
A number of different technologies were previously deployed with essentially identical goals, such as Frame Relay and ATM. Frame Relay and ATM use
2341:
1111:
798:. Due to the forwarding of packets through an LSP being opaque to higher network layers, an LSP is also sometimes referred to as an MPLS tunnel.
1979:
Raza; et al. (2005), "Online routing of bandwidth guaranteed paths with local restoration using optimized aggregate usage information",
2058:
Kodialam; et al. (2001), "Dynamic
Routing of Locally Restorable Bandwidth Guaranteed Tunnels using Aggregated Link Usage Information",
1609:
2213:
1879:
RFC 4875: Extensions to
Resource Reservation Protocol-Traffic Engineering (RSVP-TE) for Point-to-Multipoint TE Label Switched Paths (LSPs)
1151:
In some applications, the packet presented to the LER already may have a label, so that the new LER pushes a second label onto the packet.
1090:
895:(CSPF) algorithm, or are configured as a loose route that avoids a particular IP address or that is partly explicit and partly dynamic.
530:. This is a type of router located in the middle of an MPLS network. It is responsible for switching the labels used to route packets.
1936:
1642:
1237:
852:
Multicast was, for the most part, an afterthought in MPLS design. It was introduced by point-to-multipoint RSVP-TE. It was driven by
162:
that the frame or cell resides on. The similarity between Frame Relay, ATM, and MPLS is that at each hop throughout the network, the
2305:
2300:"Deploying IP and MPLS QoS for Multiservice Networks: Theory and Practice" by John Evans, Clarence Filsfils (Morgan Kaufmann, 2007,
2267:
2075:
1996:
1029:
Both ATM and MPLS support tunneling of connections inside connections. MPLS uses label stacking to accomplish this while ATM uses
339:
175:
full-length 1500 byte packets do not incur significant real-time queuing delays. At the same time, MPLS attempts to preserve the
892:
498:
The presence of such a label has to be indicated to the switch. In the case of
Ethernet frames this is done through the use of
283:
128:
2335:
2316:
2188:
1494:
1262:
300:
140:
1057:. It is deployed to connect as few as two facilities to very large deployments. In practice, MPLS is mainly used to forward
983:(telcos) to their customers, as clients were unlikely to be utilizing a data service 100 percent of the time. Consequently,
979:
aimed to make more efficient use of existing physical resources, which allow for the underprovisioning of data services by
837:
685:
operation the label is swapped with a new label, and the packet is forwarded along the path associated with the new label.
614:
664:
When a labeled packet is received by an MPLS router, the topmost label is examined. Based on the contents of the label a
2367:
1214:
927:
918:
IP routing are shown as hops in the path, thus not the MPLS nodes used in between, therefore when you see that a packet
643:
295:
1357:
Rekhter, Y.; Davie, B.; Rosen, E.; Swallow, G.; Farinacci, D.; Katz, D. (1997). "Tag switching architecture overview".
880:
2362:
1062:
829:
775:
610:
171:
541:. The old label is then removed from the header and replaced with the new label before the packet is routed forward.
994:; its use in different geographic areas depended greatly on governmental and telecommunication companies' policies.
987:
of capacity by the telcos, while financially advantageous to the provider, can directly affect overall performance.
2232:
2023:
Li Li; et al. (2005), "Routing bandwidth guaranteed paths with local restoration in label switched networks",
1119:
1115:
1006:
820:
is considered, LSPs can be categorized as primary (working), secondary (backup) and tertiary (LSP of last resort).
132:
73:
45:
794:
path removes the label from the packet and forwards the packet based on the header of its next layer, for example
2253:
Joseph M. Soricelli with John L. Hammond, Galina Diker
Pildush, Thomas E. Van Meter, Todd M. Warble (June 2003).
872:
771:
627:
120:
863:) was also introduced by IETF. HSMP LSP is mainly used for multicast, time synchronization, and other purposes.
735:
Usually, the last label is popped off at the penultimate hop (the hop before the egress router). This is called
2357:
900:
809:. Routers in between, which need only swap labels, are called transit routers or label switch routers (LSRs).
711:
operation the label is removed from the packet, which may reveal an inner label below. This process is called
630:(PVCs) in ATM or Frame Relay networks, except that they are not dependent on a particular layer-2 technology.
1875:
R. Aggarwal; D. Papadimitriou; S. Yasukawa (May 2007), Aggarwal, R.; Papadimitriou, D.; Yasukawa, S. (eds.),
107:
MPLS operates at a layer that is generally considered to lie between traditional definitions of OSI Layer 2 (
841:
736:
582:
562:
533:
When an LSR receives a packet, it uses the label included in the packet header as an index to determine the
176:
101:
81:
1278:
Chandranmenon, Girish P.; Varghese, George (October 1995), "Trading Packet
Headers for Packet Processing",
311:
MPLS works by prefixing packets with an MPLS header, containing one or more labels. This is called a label
1958:
NPP: A Facility Based
Computation Framework for Restoration Routing Using Aggregate Link Usage Information
953:
538:
312:
207:
53:
1023:
949:
939:
724:
forwarding that does not need to look at a protocol-dependent routing table and avoids the expensive IP
1184:
This is the default behavior with only one label in the stack, accordingly to the MPLS specification.
899:
available bandwidth will be chosen. MPLS Traffic Engineering relies upon the use of TE extensions to
725:
697:
594:
230:
1464:
Multiprotocol Label Switching (MPLS) Label Stack Entry: "EXP" Field Renamed to "Traffic Class" Field
1065:(VPLS) Ethernet traffic. Major applications of MPLS are telecommunications traffic engineering, and
180:
56:, the labels identify established paths between endpoints. MPLS can encapsulate packets of various
1667:"Configuring Ultimate-Hop Popping for LSPs - Technical Documentation - Support - Juniper Networks"
2277:
2254:
2081:
2040:
2002:
743:
639:
335:
324:
155:
2100:
1773:
L. Andersson; I. Minei; B. Thomas (October 2007), Andersson, L.; Minei, I.; Thomas, B. (eds.),
1690:
Dino, Farinacci; Guy, Fedorkow; Alex, Conta; Yakov, Rekhter; C., Rosen, Eric; Tony, Li (2001).
278:
with its Tag Distribution Protocol (TDP). It was a Cisco proprietary proposal, and was renamed
158:
or cells through a network. The header of the Frame Relay frame and the ATM cell refers to the
2312:
2301:
2263:
2194:
2184:
2122:
2071:
1992:
1932:
1717:
1648:
1638:
1490:
1258:
1233:
1058:
980:
491:
was faster than a routing table lookup because switching could take place directly within the
52:
to the next based on labels rather than network addresses. Whereas network addresses identify
49:
871:
MPLS works in conjunction with the Internet Protocol (IP) and its routing protocols, usually
2063:
2032:
1984:
1956:
1908:
1884:
1858:
1834:
1806:
1782:
1749:
1699:
1519:
1468:
1444:
1366:
1339:
1311:
1287:
1050:
984:
952:
meets the requirements of real-time applications with recovery times comparable to those of
853:
534:
259:
65:
57:
1139:
817:
598:
492:
488:
203:
159:
108:
97:
1384:
1014:
for ATM) there still remain significant differences in the behavior of the technologies.
747:
483:
These MPLS-labeled packets are switched based on the label instead of a lookup in the IP
638:
When an unlabeled packet enters the ingress router and needs to be passed on to an MPLS
1038:
991:
910:
For end-users the use of MPLS is not visible directly, but can be assumed when doing a
802:
586:
270:
technology, which was defined only to work over ATM, did not achieve market dominance.
2351:
2044:
1421:
806:
654:
601:(P) routers. The job of a P router is significantly easier than that of a PE router.
590:
484:
271:
127:
service model. It can be used to carry many different kinds of traffic, including IP
112:
2085:
2006:
1142:
e.g., to support voice traffic was the motivation for the small-cell nature of ATM.
357:
349:
flag. If this is set, it signifies that the current label is the last in the stack.
17:
719:
the MPLS tunnel. This can be done by the egress router, or at the penultimate hop.
1799:
D. Awduche; L. Berger; D. Gan; T. Li; V. Srinivasan; G. Swallow (December 2001),
990:
Telcos often sold Frame Relay to businesses looking for a cheaper alternative to
597:(PE) routers. Devices that function only as transit routers are similarly called
565:
this function may instead be performed by the LSR directly connected to the LER.
537:
on the label-switched path (LSP) and a corresponding label for the packet from a
1738:
1402:
1054:
976:
876:
805:. The last router in an LSP, which pops the label from the packet, is called an
569:
211:
136:
77:
31:
2067:
64:
component of the name. MPLS supports a range of access technologies, including
1085:(GMPLS) to also allow the creation of LSPs in non-native IP networks, such as
1077:
MPLS was originally proposed to allow high-performance traffic forwarding and
911:
658:
167:
119:
protocol. It was designed to provide a unified data-carrying service for both
2198:
2036:
1988:
1652:
1437:
V. Sharma; F. Hellstrand (February 2003), Sharma, V.; Hellstrand, F. (eds.),
1005:
While the underlying protocols and technologies are different, both MPLS and
573:
label and forwards the resulting IP packet using normal IP forwarding rules.
183:
that made Frame Relay and ATM attractive for deploying large-scale networks.
1440:
RFC 3469: Framework for Multi-Protocol Label Switching (MPLS)-based Recovery
770:
A label-switched path (LSP) is a path through an MPLS network set up by the
650:
507:
499:
94:
69:
840:(RSVP) for traffic engineering. Furthermore, there exist extensions of the
1291:
692:
operation a new label is pushed on top of the existing label, effectively
274:
introduced a related proposal, not restricted to ATM transmission, called
2154:
1066:
883:(PWE3) that are capable of transporting a variety of transport payloads (
860:
701:
518:
An MPLS router that performs routing based only on the label is called a
197:
144:
124:
1637:. Smith, David J. (Computer engineer). Indianapolis, Ind.: Cisco Press.
833:
779:
503:
252:
1741:
1691:
1556:
1539:
1462:
1331:
1305:
1981:
IEEE International Conference on Communications, 2005. ICC 2005. 2005
1913:
1902:
1888:
1877:
1862:
1852:
1838:
1827:
1811:
1800:
1786:
1775:
1753:
1703:
1524:
1513:
1472:
1448:
1438:
1370:
1343:
1316:
787:
1635:
Router security strategies : securing IP network traffic planes
210:
published paper on threaded indices, a form of label switching, at
2141:
2062:, IEEE Infocom. pp. 376–385. 2001, vol. 1, pp. 376–385,
1961:, QoS-IP 2005 : quality of service in multiservice IP network
1086:
957:
904:
828:
There are two standardized protocols for managing MPLS paths: the
801:
The router which first prefixes the MPLS header to a packet is an
715:. If the popped label was the last on the label stack, the packet
2329:
2099:
Tran Cong Hung, Le Quoc Cuong, Tran Thi Thuy Mai (10 Feb 2019).
1904:
RFC 3985: Pseudo Wire Emulation Edge-to-Edge (PWE3) Architecture
1106:
1102:
1011:
945:
888:
884:
795:
1572:
1026:, allowing data to flow in both directions over the same path.
2108:
International Conference on Advanced Communications Technology
1901:
S. Bryant; P. Pate (March 2005), Bryant, S.; Pate, P. (eds.),
1610:"6PE FAQ: Why Does 6PE Use Two MPLS Labels in the Data Plane?"
1010:
differences in the signaling protocols (RSVP/LDP for MPLS and
783:
1385:"IETF - Tag Distribution Protocol (draft-doolan-tdp-spec-00)"
217:
1996: Ipsilon, Cisco and IBM announced label switching plans
123:-based clients and packet-switching clients which provide a
166:
value in the header is changed. This is different from the
1255:
Applied Data Communications (A Business-Oriented Approach)
609:
Labels may be distributed between LERs and LSRs using the
1742:"Removing a Restriction on the use of MPLS Explicit NULL"
1332:"Ipsilon Flow Management Protocol Specification for IPv4"
1253:
Goldman, James E.; Rawles, Phillip T. (12 January 2004).
27:
Network routing scheme based on labels identifying paths
2214:"An Informal Guide to the Engines of Packet Forwarding"
1854:
RFC 4781: Graceful Restart Mechanism for BGP with MPLS
1586:"Understanding MPLS Explicit and Implicit Null Labels"
1571:
Savecall telecommunication consulting company Germany
315:. Each entry in the label stack contains four fields:
1802:
RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels
1515:
RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs)
856:
requirements to transport broadband video over MPLS.
2027:, IEEE Journal on Selected Areas in Communications,
1304:
E. Rosen; A. Viswanathan; R. Callon (January 2001),
922:
between two very distant nodes and hardly any other
790:). The path is set up based on criteria in the FEC.
1307:
RFC3031: Multiprotocol Label Switching Architecture
1193:
Both SVC and PVC ATM connections are bidirectional.
1876:
1826:
1774:
653:perspective, the MPLS Header is added between the
323:value. A label with the value of 1 represents the
1403:"Multiprotocol Label Switching (mpls) WG History"
696:the packet in another layer of MPLS. This allows
2025:IEEE Journal on Selected Areas in Communications
1983:, IEEE-ICC 2005, vol. 1, pp. 201–207,
561:it off an outgoing packet. Alternatively, under
1215:"What is Multiprotocol Label Switching (MPLS)?"
844:(BGP) that can be used to manage an MPLS path.
223:1999: First MPLS VPN (L3VPN) and TE deployments
1558:RFC 2205: Resource ReSerVation Protocol (RSVP)
220:1997: Formation of the IETF MPLS working group
30:"MPLS" redirects here. For the U.S. city, see
1829:RFC 3107: Carrying Label Information in BGP-4
8:
2282:: CS1 maint: multiple names: authors list (
2127:: CS1 maint: multiple names: authors list (
1722:: CS1 maint: multiple names: authors list (
930:) it is very likely that network uses MPLS.
196:presented Cell Switch Router (CSR) ideas to
2101:"A Study on Any Transport over MPLS (AToM)"
742:Several MPLS services including end-to-end
342:). Prior to 2009 this field was called EXP.
93:is to eliminate dependence on a particular
2231:Richard A Steenbergen (June 13–16, 2010).
1507:
1505:
905:Intermediate System to Intermediate System
700:of MPLS packets. Notably, this is used by
557:an MPLS label onto an incoming packet and
495:and avoided CPU and software involvement.
1912:
1810:
1523:
1315:
1280:ACM SIGCOMM Computer Communication Review
581:In the specific context of an MPLS-based
1950:
1948:
1851:Y. Rekhter; R. Aggarwal (January 2007),
1461:L. Andersson; R. Asati (February 2009),
363:
2181:Advanced MPLS design and implementation
2018:
2016:
1206:
1131:
1081:in IP networks. However, it evolved in
926:is seen in that provider's network (or
2275:
2120:
1715:
1555:R. Braden; L. Zhang (September 1997),
1512:E. Rosen; Y. Rekhter (February 2006),
115:), and thus is often referred to as a
2311:Rick Gallaher's MPLS Training Guide (
2212:Salah M. S. Buraiky (December 2018).
1485:Ivan Pepelnjak; Jim Guichard (2002),
1423:Computer Networks: A Systems Approach
7:
1487:MPLS and VPN Architectures, Volume 1
1091:wavelength switched optical networks
1049:MPLS is standardized by the IETF in
2183:. Indianapolis, Ind.: Cisco Press.
1538:B. Thomas; E. Gray (January 2001),
1330:P. Newman; et al. (May 1996).
774:or by a signaling protocol such as
859:The hub and spoke multipoint LSP (
642:, the router first determines the
25:
1955:Aslam; et al. (2005-02-02),
1931:. Cisco Press. pp. 249–326.
1825:Y. Rekhter; E. Rosen (May 2001),
1420:L. Peterson and B. Davie (2022).
881:Pseudowire Emulation Edge-to-Edge
867:Relationship to Internet Protocol
732:router has no such requirement.
471:TC: Traffic Class (QoS and ECN)
340:Explicit Congestion Notification
1061:protocol data units (PDUs) and
960:rings of less than 50 ms.
893:Constrained Shortest Path First
284:Internet Engineering Task Force
248:2009: Label Switching Multicast
502:values 0x8847 and 0x8848, for
301:synchronous optical networking
239:2004: GMPLS; Large-scale L3VPN
226:2000: MPLS Traffic Engineering
141:Synchronous Optical Networking
1:
838:Resource Reservation Protocol
824:Installing and removing paths
615:Resource Reservation Protocol
585:(VPN), LERs that function as
38:Multiprotocol Label Switching
1740:>, Eric C. Rosen (2005).
981:telecommunications companies
644:forwarding equivalence class
593:to the VPN are often called
282:. It was handed over to the
242:2006: Large-scale TE "Harsh"
172:connection-oriented services
44:) is a routing technique in
1777:RFC 5036: LDP Specification
1692:"MPLS Label Stack Encoding"
1541:RFC 3037: LDP Applicability
1489:, Cisco Press, p. 27,
1063:Virtual Private LAN Service
830:Label Distribution Protocol
611:Label Distribution Protocol
605:Label Distribution Protocol
487:. When MPLS was conceived,
48:that directs data from one
46:telecommunications networks
2384:
2068:10.1109/INFCOM.2001.916720
1101:MPLS can exist in both an
1001:Asynchronous Transfer Mode
937:
873:interior gateway protocols
628:permanent virtual circuits
510:connections respectively.
467:
133:Asynchronous Transfer Mode
29:
2256:Juniper JNCIA Study Guide
757:2: Explicit-null for IPv6
754:0: Explicit-null for IPv4
476:
473:
470:
2037:10.1109/JSAC.2004.839424
1989:10.1109/ICC.2005.1494347
1633:Gregg., Schudel (2008).
901:Open Shortest Path First
264:flow management protocol
168:forwarding of IP packets
102:packet-switched networks
2342:A brief history of MPLS
2179:Alwayn, Vivek. (2002).
1359:Proceedings of the IEEE
1138:The desire to minimize
842:Border Gateway Protocol
786:(or the now deprecated
737:penultimate hop popping
583:virtual private network
563:penultimate hop popping
245:2007: Large-scale L2VPN
2336:MPLS IP Specifications
1927:Ghein, Luc De (2007).
1228:Ghein, Luc De (2007).
954:shortest path bridging
836:, an extension of the
539:Label Information Base
253:MPLS transport profile
1292:10.1145/217391.217427
950:MPLS local protection
940:MPLS local protection
934:MPLS local protection
914:: only nodes that do
258:In 1996 a group from
208:Girish Chandranmenon
848:Multicast addressing
726:longest prefix match
698:hierarchical routing
621:Label-switched paths
338:) priority and ECN (
299:protection rings of
231:Request for Comments
131:, as well as native
88:Role and functioning
2368:Tunneling protocols
1097:Competing protocols
1079:traffic engineering
766:Label-switched path
568:When forwarding an
520:label switch router
514:Label switch router
474:S: Bottom-of-Stack
366:
181:out-of-band control
177:traffic engineering
18:Label switch router
2363:Internet Standards
2338:, Broadband Forum.
2330:MPLS Working Group
2233:"MPLS for Dummies"
1087:SONET/SDH networks
477:TTL: Time-to-Live
364:
336:quality of service
325:router alert label
236:2002: AToM (L2VPN)
2155:"Is MPLS faster?"
1929:MPLS Fundamentals
1391:. September 1996.
1365:(12): 1973–1983.
1230:MPLS Fundamentals
551:label edge router
545:Label edge router
481:
480:
229:2001: First MPLS
214:annual conference
58:network protocols
16:(Redirected from
2375:
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1832:
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1812:10.17487/RFC3209
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1787:10.17487/RFC5036
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1754:10.17487/RFC4182
1734:
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1704:10.17487/RFC3032
1687:
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1473:10.17487/RFC5462
1458:
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1449:10.17487/RFC3469
1434:
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1399:
1393:
1392:
1381:
1375:
1374:
1371:10.1109/5.650179
1354:
1348:
1347:
1344:10.17487/RFC1953
1327:
1321:
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1319:
1317:10.17487/RFC3031
1301:
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1185:
1182:
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1170:
1164:
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1152:
1149:
1143:
1136:
1083:Generalized MPLS
985:oversubscription
854:service provider
746:management, and
367:
260:Ipsilon Networks
233:(RFCs) published
21:
2383:
2382:
2378:
2377:
2376:
2374:
2373:
2372:
2358:MPLS networking
2348:
2347:
2326:
2297:
2295:Further reading
2292:
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2259:
2252:
2251:
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2110:
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2057:
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2021:
2014:
1999:
1978:
1977:
1973:
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1939:
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1714:
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1675:
1673:
1671:www.juniper.net
1665:
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1631:
1627:
1618:
1616:
1608:
1607:
1603:
1594:
1592:
1583:
1582:
1578:
1573:Savecall - MPLS
1570:
1566:
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1549:
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1511:
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1497:
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1324:
1303:
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1247:
1240:
1232:. Cisco Press.
1227:
1226:
1222:
1213:
1212:
1208:
1203:
1198:
1197:
1192:
1188:
1183:
1179:
1171:
1167:
1159:
1155:
1150:
1146:
1140:network latency
1137:
1133:
1128:
1099:
1075:
1047:
1003:
992:dedicated lines
974:
966:
948:. In contrast,
942:
936:
869:
850:
826:
818:link protection
768:
636:
623:
607:
579:
577:Provider router
547:
516:
493:switched fabric
489:label switching
347:bottom of stack
334:field for QoS (
309:
280:Label Switching
204:George Varghese
189:
160:virtual circuit
111:) and Layer 3 (
109:data link layer
98:data link layer
90:
35:
28:
23:
22:
15:
12:
11:
5:
2381:
2379:
2371:
2370:
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2345:
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2324:External links
2322:
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2320:
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2290:
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2268:
2245:
2223:
2218:Juniper Forums
2204:
2189:
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2159:www.802101.com
2146:
2134:
2091:
2076:
2050:
2031:(2): 437–449,
2012:
1997:
1971:
1944:
1938:978-1587051975
1937:
1919:
1893:
1867:
1843:
1817:
1791:
1765:
1746:tools.ietf.org
1729:
1696:tools.ietf.org
1682:
1658:
1644:978-1587053368
1643:
1625:
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1426:. p. 336.
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1286:(4): 162–173,
1270:
1263:
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1239:978-1587051975
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1046:
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1039:network design
1002:
999:
973:
970:
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962:
938:Main article:
935:
932:
868:
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846:
825:
822:
803:ingress router
767:
764:
759:
758:
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603:
591:egress routers
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2144:I.150 3.1.3.1
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1591:
1590:Network World
1587:
1584:Doyle, Jeff.
1580:
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1031:virtual paths
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1024:bidirectional
1019:
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807:egress router
804:
799:
797:
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773:
765:
763:
756:
753:
752:
751:
749:
745:
740:
738:
733:
729:
728:at each hop.
727:
718:
714:
713:decapsulation
710:
706:
703:
699:
695:
694:encapsulating
691:
687:
684:
680:
679:
678:
675:
671:
667:
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655:network layer
652:
647:
645:
641:
633:
631:
629:
620:
618:
616:
612:
604:
602:
600:
596:
595:provider edge
592:
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571:
566:
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536:
531:
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485:routing table
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456:
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450:
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351:
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341:
337:
333:
332:Traffic Class
329:
326:
322:
318:
317:
316:
314:
306:
304:
303:(SONET/SDH).
302:
297:
291:
287:
285:
281:
277:
276:Tag Switching
273:
272:Cisco Systems
269:
265:
261:
254:
250:
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244:
241:
238:
235:
232:
228:
225:
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118:
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113:network layer
110:
105:
103:
99:
96:
87:
85:
83:
79:
75:
71:
67:
63:
62:multiprotocol
59:
55:
51:
47:
43:
39:
33:
19:
2255:
2248:
2239:
2226:
2217:
2207:
2180:
2174:
2163:. Retrieved
2161:. 2017-08-04
2158:
2149:
2137:
2111:. Retrieved
2107:
2094:
2059:
2053:
2028:
2024:
1980:
1974:
1963:, retrieved
1957:
1928:
1922:
1903:
1896:
1878:
1870:
1853:
1846:
1828:
1820:
1801:
1794:
1776:
1768:
1757:. Retrieved
1745:
1732:
1707:. Retrieved
1695:
1685:
1674:. Retrieved
1670:
1661:
1634:
1628:
1617:. Retrieved
1613:
1604:
1593:. Retrieved
1589:
1579:
1567:
1557:
1550:
1540:
1533:
1514:
1486:
1480:
1463:
1456:
1439:
1432:
1422:
1415:
1406:
1397:
1388:
1379:
1362:
1358:
1352:
1335:
1325:
1306:
1299:
1283:
1279:
1273:
1254:
1248:
1229:
1223:
1209:
1189:
1180:
1173:
1168:
1161:
1156:
1147:
1134:
1100:
1076:
1048:
1035:
1030:
1028:
1020:
1016:
1004:
996:
989:
975:
967:
956:networks or
943:
923:
919:
915:
909:
897:
870:
858:
851:
827:
815:
811:
800:
792:
769:
760:
741:
734:
730:
722:
716:
712:
708:
693:
689:
682:
673:
669:
665:
663:
648:
637:
624:
608:
580:
567:
558:
554:
550:
548:
532:
527:
523:
519:
517:
497:
482:
358:time to live
353:
346:
331:
320:
310:
292:
288:
279:
275:
268:IP Switching
267:
263:
257:
163:
151:
149:
116:
106:
91:
61:
60:, hence the
41:
37:
36:
977:Frame Relay
972:Frame Relay
964:Comparisons
877:pseudowires
657:header and
570:IP datagram
365:MPLS label
262:proposed a
212:ACM SIGCOMM
143:(SONET) or
137:Frame Relay
78:Frame Relay
32:Minneapolis
2352:Categories
2317:1932266003
2190:158705020X
2165:2017-08-05
2113:5 February
1965:2006-10-27
1759:2018-03-13
1709:2018-03-13
1676:2018-03-13
1619:2018-03-13
1595:2018-03-13
1496:1587050811
1264:0471346403
1201:References
1045:Deployment
912:traceroute
903:(OSPF) or
832:(LDP) and
659:link layer
2278:cite book
2262:. Wiley.
2199:656875465
2045:195347236
1653:297576680
1257:. Wiley.
1073:Evolution
702:MPLS VPNs
651:OSI model
613:(LDP) or
508:multicast
500:EtherType
352:An 8-bit
319:A 20-bit
307:Operation
179:(TE) and
117:layer 2.5
95:OSI model
54:endpoints
2123:cite web
2086:13870642
1907:, IETF,
1883:, IETF,
1857:, IETF,
1833:, IETF,
1805:, IETF,
1781:, IETF,
1718:cite web
1518:, IETF,
1467:, IETF,
1443:, IETF,
1338:. IETF.
1336:RFC 1953
1310:, IETF,
1067:MPLS VPN
861:HSMP LSP
661:header.
649:From an
599:provider
535:next hop
360:) field.
345:A 1-bit
330:A 3-bit
266:. Their
198:IETF BOF
154:to move
145:Ethernet
125:datagram
2332:, IETF.
2007:5659648
1174:dispose
1172:A.k.a.
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780:RSVP-TE
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