EP1500238A1 - Procede pour controler la continuite de liaisons dans des reseaux mpls - Google Patents

Procede pour controler la continuite de liaisons dans des reseaux mpls

Info

Publication number
EP1500238A1
EP1500238A1 EP03727218A EP03727218A EP1500238A1 EP 1500238 A1 EP1500238 A1 EP 1500238A1 EP 03727218 A EP03727218 A EP 03727218A EP 03727218 A EP03727218 A EP 03727218A EP 1500238 A1 EP1500238 A1 EP 1500238A1
Authority
EP
European Patent Office
Prior art keywords
oam
mpls
packets
connection
echo
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP03727218A
Other languages
German (de)
English (en)
Inventor
Joachim Klink
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nokia Solutions and Networks GmbH and Co KG
Original Assignee
Siemens AG
Nokia Siemens Networks GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG, Nokia Siemens Networks GmbH and Co KG filed Critical Siemens AG
Publication of EP1500238A1 publication Critical patent/EP1500238A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L43/00—Arrangements for monitoring or testing data switching networks
    • H04L43/50—Testing arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/50—Routing or path finding of packets in data switching networks using label swapping, e.g. multi-protocol label switch [MPLS]

Definitions

  • the invention relates to a method according to the preamble of claim 1.
  • the OAM functionality (Operation and Maintenance) is to be regarded as an essential part of the operation of public communication networks. It supports the quality of the network performance while reducing the operating costs of the network. It makes a significant contribution, particularly with regard to the quality of service of the information transmitted (QoS).
  • QoS quality of service of the information transmitted
  • the operator of a communication network can obtain information at any time as to whether the quality of service guaranteed for a connection (service level agreement) is also being met. For this, the operator must know the availability of existing connections (connection "up * or” down ") as well as the time delay in the transmission of the information (delay, delay variation), the - possibly averaged - deviation from the otherwise usual distance between each two information transmissions (delay jitter), or the number of information not even allowed to be transmitted (blocking rate, error performance).
  • MPLS networks are currently proposed for the transmission of information on the Internet.
  • MPLS networks Multiprotocol Packet Label Switching
  • information is transmitted using MPLS packets.
  • MPLS packets have a variable length, each with a header and an information part.
  • the header is used to record connection information, while the information section is useful for recording useful information.
  • IP packets are used as useful information.
  • the connection information contained in the header is designed as an MPLS connection number. However, this is only valid in the MPLS network.
  • Fig. 1 it is assumed as an example that information such. B. can be supplied from a subscriber TLN1 to a subscriber TLN2.
  • the sending subscriber TLN1 is connected to the Internet network IP, through which the information is passed according to an Internet protocol, such as the IP protocol. This protocol is not a connection-oriented protocol.
  • the Internet network IP has a plurality of routers R, which can be meshed with one another.
  • the receiving subscriber TLN2 is connected to a further Internet network IP.
  • An MPLS network is inserted between the two Internet networks IP, through which information in the form of MPLS packets is switched through in a connection-oriented manner. This network also has a plurality of routers nibbled together.
  • LSR label switched routers
  • QoS quality of service
  • the invention has for its object to show a way how information about the continuity of connections in MPLS networks can be provided with little effort.
  • the invention is achieved on the basis of the features specified in the preamble of claim 1 by the characterizing features.
  • An advantage of the invention is in particular the provision of specially designed MPLS-OAM packets which are inserted into the traffic flow of user data packets.
  • MPLS-OAM packets which are inserted into the traffic flow of user data packets.
  • another identifier is required.
  • the packets thus defined (hereinafter referred to as OAM-ECHO packets) are used to monitor the connectivity of an MPLS connection by inserting each of these packets into the traffic flow, where it is fed to further communication devices along the connection. The OAM-ECHO packet is then copied, buffered and routed in the communication devices.
  • the copied and cached packet is then sent back in the opposite direction towards the source, where all incoming copies are registered until the OAM-ECHO packet has either been extracted in the OAM sink or the connection has been interrupted at some point.
  • LSP continuity of the connection
  • FIG 1 shows the basic conditions in an MPLS network
  • Figure 2 shows an end-to-end connection between two participants
  • Figure 3 shows the relationships in the packet header and in the information part of an MPLS-OAM packet
  • LSP Lable Switched Path
  • the nodes N1 ... N4 should be designed as routers LSR of an MPLS network.
  • an information flow arises between the subscriber TLN1 and the subscriber TLN2, which is formed from a plurality of MPLS packets carrying the user data.
  • MPLS-OAM packets can be inserted into this MPLS packet flow (inband LSP).
  • connections are defined via which only MPLS-OAM packets are routed (outband LSP).
  • in-band MPLS-OAM packets are useful for logging LSP connections on an individual basis. However, in some cases it may be more advantageous to define an out-of-band MPLS-OAM packet flow.
  • An example of this is the MPLS group equivalent circuit.
  • the MPLS-OAM packets are marked. The special marking mechanisms are shown in FIG. 3 and will be described in more detail later.
  • the sequence of several MPLS-OAM packets defines an MPLS-OAM packet flow. Basically, 3 different types of MPLS-OAM packet flow can exist simultaneously for an LSP connection:
  • End-to-end MPLS-OAM packet flow It is used in particular when OAM communication takes place between a source and a sink of an LSP connection. It is formed from MPLS-OAM packets, which are inserted in the source of the connection LSP in the user data stream and are taken out again at the sink. The MPLS-OAM packets can be recorded and monitored along the connection LSP to the connection point CP without interfering with the transmission process (passive monitoring).
  • the MPLS-OAM packet flow of type A is distinguished from the end-to-end defined MPLS-OAM packet flow. It is used in particular when OAM communication takes place between the nodes which delimit a connection section (segment) of type A (FIG. 2).
  • One or more Type A MPLS-OAM segments can be defined in the LSP connection, but they cannot be nested nor can they overlap with other Type A segments.
  • the MPLS-OAM packet flow of type B is finally distinguished from the two types of packet flow mentioned above. It is used in particular when OAM communication takes place between the nodes which delimit a type B connection section (FIG. 2).
  • One or more Type B MPLS OAM segments can be defined in the LSP connection, but they cannot be nested nor can they overlap with other Type B segments.
  • an MPLS-OAM packet flow (end-to-end, type A, type B) is formed from MPLS-OAM packets, which are inserted into the user data stream at the beginning of a segment and removed from it again at the end of the segment. They can be recorded and edited along the connection LSP at the connection points CP without interfering with the transmission process.
  • connection point CP in the connection LSP can be configured as an MPLS-OAM source or MPLS-OAM sink, the MPLS-OAM packets originating from an MPLS-OAM source preferably as “upstream” ⁇ N are to be configured.
  • the end points (source, sink) of the associated MPLS-OAM segment must be defined.
  • the definition of source and sink for an MPLS-OAM segment is not necessarily fixed for the duration of the connection. This means that the segment in question can be reconfigured, for example, using fields in the signaling protocol.
  • the segmented MPLS-OAM packet flow (type A or type B) can be nested within an end-to-end MPLS-OAM packet flow.
  • the connection points CP can be the source / sink of a segment flow (type A or type B) as well as the end-to-end MPLS-OAM packet flow.
  • the MPLS-OAM packet flow (segment flow) of type A is functionally independent of that of type B in terms of inserting, removing and processing the MPLS-OAM packets.
  • a connection point CP can therefore be the source and sink of an OAM segment flow of type A and type B at the same time.
  • the segments of type A can overlap with those of type B.
  • type A segments can overlap with type B segments. Both segments can operate independently of one another and will therefore have no influence on one another.
  • MPLS equivalent circuits however, overlapping can lead to problems.
  • the MPLS-OAM packets can be distinguished from MPLS packets carrying user data by using one of the EXP bits in the MPLS packet header.
  • this procedure offers a very simple possibility of differentiation.
  • This bit can be checked in the sink of an MPLS-OAM segment or at the connection points CP in order to filter out MPLS-OAM packets before further evaluations are carried out.
  • one of the MPLS connection numbers (MPLS label values) No. 4 to No. 15 in the header of the MPLS packet can be used as an identifier.
  • These MPLS connection numbers have been reserved by IANA.
  • the next identifier in the stack of the assigned connection LSP must indicate what the inband OAM functionality is carried out for.
  • This approach is somewhat more complex to implement, since the hardware in the OAM sink and the connection points CP requires two MPLS stack inputs for each MPLS-OAM packet.
  • the processing must be done in real time, i.e. in the connection points CP the OAM packets must be reinserted into the flow if the sequence order is adhered to. This is imperative to ensure correct performance monitoring results in the OAM sink.
  • OAM-ECHO packets In order to monitor (verify) the continuity (connectivity) of an MPLS connection LSP, special MPLS-OAM packets, hereinafter referred to as OAM-ECHO packets, are defined.
  • OAM-ECHO packets For this purpose, the MPLS-OAM packets with a special identifier voltage (see Fig. 3).
  • the OAM-ECHO packets formed in this way are inserted into the flow of the useful information
  • Characteristic of the echo function is the fact that a single OAM-ECHO packet (downstream) sent in the source returns a plurality of packets as a response, specifically one packet for each connection point CP in a node through which the assigned connection LSP is routed. This continues until the OAM-ECHO packet is extracted in the sink, i. H. is taken from the stream of useful information, or until the continuity of the assigned connection is interrupted at any point.
  • the echo function can be operated on an end-to-end basis or segment basis.
  • segment base it is necessary to first define the limits of the MPLS-OAM segment for the assigned connection LSP. This is done by configuring the source and sink first.
  • the echo function is a very useful tool for checking the continuity of an LSP connection in an MPLS network if necessary. For example, the entire network can be checked for continuity before an MPLS network is put into operation, or special connections can be checked for a customer's complaint.
  • the echo function can be activated by an operator command for a specific connection LSP (end-to-end or segment basis) in each connection point CP.
  • LSP end-to-end or segment basis
  • the corresponding connection point CP must lie within the assigned OAM segment.
  • connection point e.g. a 5 second counter
  • Any further connection point (down- strea) forwards the OAM-ECHO packet towards the sink and at the same time creates a copy of the packet.
  • the OAM-ECHO packet is finally taken from the OAM traffic flow in the sink (ie in the sink of the segment or end-to-end).
  • the copies created at the connection points are now processed as follows:
  • the bit indicating the direction of transmission in the information part of the packet is changed from "downstream to" upstream *.
  • a location identifier is also entered in the information section of the OAM-ECHO package. This is representative of the node (node ID) of the MPLS node where the processing was carried out. The location also indicates (optionally) the assigned connection point (ingress or egress). The subsequent further processing of the package depends on whether a bidirectional or unidirectional mode of operation is to be used:
  • a feedback channel is required for the assigned connection LSP in order to send the copied OAM-ECHO packet back to the source (upstrea) where it was originally inserted (some MPLS protection switching configurations (e.g. bidirectional configuration and 1 : 1 architectures use such a feedback channel.
  • MPLS protection switching configurations e.g. bidirectional configuration and 1 : 1 architectures use such a feedback channel.
  • the same procedure can also be used in the case of the echo function:
  • the feedback channel is established by logically combining two unidirectional connections LSP to form a bidirectional whole. It is essential that both LSP connections follow the same physical route, but in opposite directions. The same network elements are traversed by both LSP connections. This procedure can be achieved by using LDP signaling methods (Label Distribution Protocol) with explicit routing, by predefining the same explicit route for both LSP connections in the forward and reverse direction.
  • LDP signaling methods Label Distribution Protocol
  • the following actions are carried out:
  • the MPLS node which originally transmitted an OAM-ECHO packet in the downstream direction, will now respond in
  • connection in the form of an upstream OAM-ECHO packet from each MPLS node (and each connection point) until the packet is either extracted in the OAM sink or the 5- Seconds counter has expired.
  • the connection is defined as interrupted.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)

Abstract

L'objectif de l'invention est de permettre de contrôler la continuité de liaisons MPLS dans des réseaux MPLS. A cet effet, des paquets MPLS-OAM (paquets OAM-ECHO), spécifiquement formés, sont introduits dans le flux de trafic de paquets de données utiles et acheminés à d'autres unités de communication le long de la liaison. Dans lesdites unités de communication, chaque paquet OAM-ECHO est copié, stocké temporairement en mémoire et rerouté. Le paquet copié et stocké temporairement en mémoire est ensuite retransmis dans le sens inverse, en direction de la source, où toutes les copies entrant sont enregistrées jusqu'à ce que le paquet OAM-ECHO soit extrait du collecteur OAM ou jusqu'à ce qu'un laps de temps prédéterminé se soit écoulé. En fonction de la réception ou non des copies de ces paquets, il est possible de déterminer si la continuité de la liaison (LSP) est assurée ou non.
EP03727218A 2002-04-29 2003-04-24 Procede pour controler la continuite de liaisons dans des reseaux mpls Withdrawn EP1500238A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10219153A DE10219153A1 (de) 2002-04-29 2002-04-29 Verfahren zur Überprüfung der Durchgängigkeit von Verbindungen in MPLS-Netzen
DE10219153 2002-04-29
PCT/DE2003/001338 WO2003094444A1 (fr) 2002-04-29 2003-04-24 Procede pour controler la continuite de liaisons dans des reseaux mpls

Publications (1)

Publication Number Publication Date
EP1500238A1 true EP1500238A1 (fr) 2005-01-26

Family

ID=29264901

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03727218A Withdrawn EP1500238A1 (fr) 2002-04-29 2003-04-24 Procede pour controler la continuite de liaisons dans des reseaux mpls

Country Status (4)

Country Link
US (1) US20050147050A1 (fr)
EP (1) EP1500238A1 (fr)
DE (1) DE10219153A1 (fr)
WO (1) WO2003094444A1 (fr)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7626947B2 (en) * 2003-08-27 2009-12-01 Telefonaktiebolaget L M Ericsson (Publ) Dynamic OAM for signaled connections (DOSC)
WO2006003241A1 (fr) * 2004-06-30 2006-01-12 Nokia Corporation Detection de defaillance d'informations acheminables correspondant a une voie de transmission
CN100403687C (zh) * 2005-03-29 2008-07-16 华为技术有限公司 在多协议标签交换网络中实现分域管理和保护的方法
US7903565B2 (en) * 2005-08-12 2011-03-08 Alcatel Method of monitoring a tandem connection in a MPLS telecommunication network
CN100403704C (zh) * 2006-03-24 2008-07-16 华为技术有限公司 一种近端节点检测故障的方法
CN101136788A (zh) * 2006-08-30 2008-03-05 华为技术有限公司 一种mpls组播的故障定位方法及系统
CN101193052B (zh) * 2006-11-22 2011-06-01 华为技术有限公司 在多协议标签交换中实现子网连接保护的方法和系统
CN101826989B (zh) 2009-03-02 2013-11-06 华为技术有限公司 一种故障处理方法和装置
US9450779B2 (en) 2010-05-10 2016-09-20 Hewlett Packard Enterprise Development Lp Edge link discovery
US9094337B2 (en) * 2012-12-21 2015-07-28 Cieno Corporation Source identification preservation in multiprotocol label switching networks
US10270691B2 (en) 2016-02-29 2019-04-23 Cisco Technology, Inc. System and method for dataplane-signaled packet capture in a segment routing environment
US10270690B2 (en) 2016-02-29 2019-04-23 Cisco Technology, Inc. System and method for dataplane-signaled packet capture in IPV6 environment
US10284429B1 (en) 2018-08-08 2019-05-07 Cisco Technology, Inc. System and method for sharing subscriber resources in a network environment
US11558288B2 (en) * 2018-09-21 2023-01-17 Cisco Technology, Inc. Scalable and programmable mechanism for targeted in-situ OAM implementation in segment routing networks
WO2022212180A1 (fr) 2021-03-31 2022-10-06 Illumina, Inc. Appelant de base à base d'intelligence artificielle avec reconnaissance contextuelle
CN115225732A (zh) * 2021-04-21 2022-10-21 华为技术有限公司 一种操作维护管理oam检测方法及装置

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8199649B2 (en) * 2001-03-28 2012-06-12 Alcatel Lucent Method and apparatus for rerouting a connection in a data communication network based on a user connection monitoring function

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO03094444A1 *

Also Published As

Publication number Publication date
WO2003094444A1 (fr) 2003-11-13
DE10219153A1 (de) 2003-11-20
US20050147050A1 (en) 2005-07-07

Similar Documents

Publication Publication Date Title
EP1500237A1 (fr) Procede pour controler la disponibilite de liaisons dans des reseaux mpls
EP1500238A1 (fr) Procede pour controler la continuite de liaisons dans des reseaux mpls
DE69634611T2 (de) Selbstheilendes netzwerk
DE60008105T2 (de) Auf einem Sender basierende pfadgeschützte Vermittlung in einem Ringnetzwerk
EP1500236B1 (fr) Procede pour surveiller la qualite de transmission de liaisons dans des reseaux mpls
EP1502396A1 (fr) Procede pour accepter des circuits equivalents dans des reseaux mpls
DE69628724T2 (de) Netzknotenvorrichtung und Verbindungsaufbauverfahren zum Aufbauen von Durchgangsverbindungen
WO2003030468A2 (fr) Procede et dispositif d'adaptation de chemins a commutation d'etiquettes dans des reseaux paquets
DE60212108T2 (de) Selektiver Schutz für Ringtopologien
EP1130853A1 (fr) Dispositif de circuit pour la commutation de substitution d' installations de transmission dans des architectures d' anneau avec des paquets de MPLS
EP1262084B1 (fr) Procede de commutation de remplacement de dispositifs de transmission dans les reseaux mpls
DE60214842T2 (de) Verfahren und Vorrichtung zur Verwaltung eines Telekommunikationsnetzwerkes
EP0937370A1 (fr) Commutation sur circuit equivalent d'unites de transmission aux fins du transfert bidirectionnel de cellules en mode asynchrone
EP1488582A1 (fr) Procede de fonctionnement et de surveillance de reseaux mpls
EP1410576B1 (fr) Procede de commutation de remplacement de dispositifs de transmission dans des architectures en boucle utilisant les paquets a commutation par etiquette multiprotocole (mpls)
DE102022203873A1 (de) Schnelles rerouting mit ausgangsport-rückschleife
EP1065823A1 (fr) Procédé de surveillance de la qualité de transmission de bits dans une transmission par paquets
WO2001062037A1 (fr) Procede de commutation de remplacement de dispositifs de transmission dans les reseaux mpls
DE20122358U1 (de) Telekommunikationssystem mit verteilten Remote-Breitbandzugangs-Servern
WO2004107675A2 (fr) Procede pour transmettre des paquets ip a une composante de commande externe d'un noeud reseau dans un reseau de communication de transmission de paquets ip presentant plusieurs noeuds reseau
EP0857003A2 (fr) Dispositif pour réaliser des circutis equivalents des dispositifs de communication dans des architectures d'anneau pour la transmission bidirectionelle des cellules ATM
DE69731830T2 (de) Nachrichtenleitweglenkungsverfahren in einem Fernmeldenetz und Vorrichtung zur Durchführung des Verfahrens
EP0984658A2 (fr) Système de télécommunication avec commutateur et concentrateur de données pour l'accès vers Internet
EP1415492A1 (fr) Procede de correction d'erreur rapide et locale en cas de defaillance de liaisons physiques individuelles dans des liaisons de telecommunication en paquets, et dispositif a systeme de telecommunication pour la mise en oeuvre de ce procede
WO2009049638A1 (fr) Procédé et dispositif d'établissement d'une communication via un réseau

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20040920

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: NOKIA SIEMENS NETWORKS GMBH & CO. KG

RAP3 Party data changed (applicant data changed or rights of an application transferred)

Owner name: NOKIA SIEMENS NETWORKS S.P.A.

17Q First examination report despatched

Effective date: 20071112

RAP3 Party data changed (applicant data changed or rights of an application transferred)

Owner name: NOKIA SIEMENS NETWORKS GMBH & CO. KG

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20080326