This document provides an overview of MPLS (Multi-Protocol Label Switching) in three minutes or less. MPLS allows routers to route packets more quickly by applying "labels" or addresses rather than examining the contents of each packet. It offers benefits like scalability, faster routing between interfaces, and private virtual connections. MPLS works by having the ingress router apply a label, and then each subsequent router routes the packet based on that label rather than looking inside the packet until the egress router removes the label and delivers the packet normally.
Migrating our micro services from Java to Kotlin (Code.Talks 2018)Björn Wendland
This talk elaborates our awesome journey migrate all our micro services from Java to Kotlin.
We will take a closer look at the challenges we faced as a team and the impact on our day to day work in an agile environment and how we overcame technical hurdles integrating with Spring Boot and introducing async workflows with Kotlin coroutines.
Finally we discuss at the actual benefits that we gained by moving all our micro services to Kotlin and do a critical review of our journey and an outlook at things to come.
Distributed OSGi Services with the Eclipse Communication Framework - Jan Rell...mfrancis
The document discusses the Eclipse Communication Framework (ECF), which provides mechanisms for distributed OSGi services. ECF allows for service discovery across networks, as well as exposing local OSGi services remotely. It has adapters for common discovery protocols like SLP and mDNS, and can be used to enable remote access to services via transports like XMPP. ECF provides both transparent and non-transparent APIs for remote services.
The document discusses using BGP dynamic routing with Neutron to route cloud network traffic. It provides an overview of Neutron's BGP dynamic routing service and applications. Currently Neutron networks use static routing, but dynamic routing would allow routes to move between routers more easily. The document outlines how Neutron could insert routes into a routing protocol to advertise to infrastructure routers. Future applications discussed include routed network segments, L3 VPNs, and directly routible tenant networks.
Openstack Neutron & Interconnections with BGP/MPLS VPNsThomas Morin
The document discusses Neutron networking-bgpvpn, an OpenStack Neutron extension that enables interconnection between OpenStack deployments and BGP/MPLS VPNs. It provides a high-level overview of networking-bgpvpn's architecture, supported drivers, features, and integration with OPNFV SDNVPN for automated deployment and testing of BGPVPN use cases. Neutron networking-bgpvpn allows tenants to define and manage their own BGP VPNs to interconnect with external networks or between distributed OpenStack installations.
Interconnecting Neutron and Network Operators' BGP VPNsThomas Morin
joint presentation given at OpenStack summit Barcelona (Oct. 2016) with Paul Carver and Tim Irnich
talk video: https://www.youtube.com/watch?v=LCDeR7MwTzE
demo: https://www.youtube.com/watch?v=5iRoZcmQyuU
The document discusses traffic engineering in networks using MPLS. It begins by defining traffic engineering and explaining how shortest path routing can lead to link congestion and underutilized paths. It then describes MPLS, constraint-based routing, and enhanced interior gateway protocols. Constraint-based routing computes paths subject to constraints like bandwidth and policies. MPLS extends routing to control packet forwarding and paths. The document outlines the basic components and functioning of an MPLS system for traffic engineering, including setting up label switched paths (LSPs) with attributes like bandwidth, priority, affinity and establishing multiple LSPs between endpoints to distribute load.
- Multi-Protocol Label Switching (MPLS) improves forwarding speed and enables new capabilities like traffic engineering and virtual private networks. It uses short fixed-length labels to represent IP packets and make forwarding decisions.
- MPLS was originally conceived as being independent of Layer 2 but has found success deploying IP networks across ATM backbones. Standards are being developed and it is seen as an important network development.
- MPLS encapsulates IP packets with labels which are then used instead of the IP header for forwarding decisions, allowing separation of the forwarding and control planes.
This document provides an introduction to Multi-Protocol Label Switching (MPLS), including its motivation, basic concepts, components, protocols, operation, advantages, and disadvantages. MPLS combines IP routing with ATM switching to address some of the limitations of IP routing, such as lack of quality of service, while being less complex and expensive than ATM. It works by assigning short, fixed-length labels to IP packets at the edge of the network which are then used for fast packet forwarding within the network core.
Migrating our micro services from Java to Kotlin (Code.Talks 2018)Björn Wendland
This talk elaborates our awesome journey migrate all our micro services from Java to Kotlin.
We will take a closer look at the challenges we faced as a team and the impact on our day to day work in an agile environment and how we overcame technical hurdles integrating with Spring Boot and introducing async workflows with Kotlin coroutines.
Finally we discuss at the actual benefits that we gained by moving all our micro services to Kotlin and do a critical review of our journey and an outlook at things to come.
Distributed OSGi Services with the Eclipse Communication Framework - Jan Rell...mfrancis
The document discusses the Eclipse Communication Framework (ECF), which provides mechanisms for distributed OSGi services. ECF allows for service discovery across networks, as well as exposing local OSGi services remotely. It has adapters for common discovery protocols like SLP and mDNS, and can be used to enable remote access to services via transports like XMPP. ECF provides both transparent and non-transparent APIs for remote services.
The document discusses using BGP dynamic routing with Neutron to route cloud network traffic. It provides an overview of Neutron's BGP dynamic routing service and applications. Currently Neutron networks use static routing, but dynamic routing would allow routes to move between routers more easily. The document outlines how Neutron could insert routes into a routing protocol to advertise to infrastructure routers. Future applications discussed include routed network segments, L3 VPNs, and directly routible tenant networks.
Openstack Neutron & Interconnections with BGP/MPLS VPNsThomas Morin
The document discusses Neutron networking-bgpvpn, an OpenStack Neutron extension that enables interconnection between OpenStack deployments and BGP/MPLS VPNs. It provides a high-level overview of networking-bgpvpn's architecture, supported drivers, features, and integration with OPNFV SDNVPN for automated deployment and testing of BGPVPN use cases. Neutron networking-bgpvpn allows tenants to define and manage their own BGP VPNs to interconnect with external networks or between distributed OpenStack installations.
Interconnecting Neutron and Network Operators' BGP VPNsThomas Morin
joint presentation given at OpenStack summit Barcelona (Oct. 2016) with Paul Carver and Tim Irnich
talk video: https://www.youtube.com/watch?v=LCDeR7MwTzE
demo: https://www.youtube.com/watch?v=5iRoZcmQyuU
The document discusses traffic engineering in networks using MPLS. It begins by defining traffic engineering and explaining how shortest path routing can lead to link congestion and underutilized paths. It then describes MPLS, constraint-based routing, and enhanced interior gateway protocols. Constraint-based routing computes paths subject to constraints like bandwidth and policies. MPLS extends routing to control packet forwarding and paths. The document outlines the basic components and functioning of an MPLS system for traffic engineering, including setting up label switched paths (LSPs) with attributes like bandwidth, priority, affinity and establishing multiple LSPs between endpoints to distribute load.
- Multi-Protocol Label Switching (MPLS) improves forwarding speed and enables new capabilities like traffic engineering and virtual private networks. It uses short fixed-length labels to represent IP packets and make forwarding decisions.
- MPLS was originally conceived as being independent of Layer 2 but has found success deploying IP networks across ATM backbones. Standards are being developed and it is seen as an important network development.
- MPLS encapsulates IP packets with labels which are then used instead of the IP header for forwarding decisions, allowing separation of the forwarding and control planes.
This document provides an introduction to Multi-Protocol Label Switching (MPLS), including its motivation, basic concepts, components, protocols, operation, advantages, and disadvantages. MPLS combines IP routing with ATM switching to address some of the limitations of IP routing, such as lack of quality of service, while being less complex and expensive than ATM. It works by assigning short, fixed-length labels to IP packets at the edge of the network which are then used for fast packet forwarding within the network core.
MPLS (Multi-Protocol Label Switching) is introduced as a "Layer 2.5" protocol that sits between traditional Layer 2 and Layer 3 networking. It works by assigning labels to packets at ingress routers and using those labels for fast forwarding decisions without additional routing lookups at subsequent routers. This improves performance over traditional IP routing. MPLS also enables traffic engineering through protocols like RSVP-TE that allow reserving bandwidth on specific paths. Other key MPLS concepts covered are label switching, MPLS signaling protocols, label stacking, pseudowires, VPN services, and fast reroute for improved convergence during failures.
MPLS is a forwarding mechanism that uses labels instead of IP addresses to forward packets. It allows routers to forward based on simple label lookups rather than complex routing lookups. MPLS has benefits like supporting multiple applications and decreasing forwarding overhead on core routers. It has a control plane that exchanges routing information and labels, and a data plane that forwards packets based on labels. Label Switch Routers implement MPLS forwarding by exchanging labels and forwarding packets based on those labels.
MPLS-TE provides fast reroute (FRR) capabilities to minimize traffic loss during network failures. FRR utilizes pre-established backup label switched paths (LSPs) to quickly switch traffic around failures without waiting for IGP convergence. This document describes different MPLS-TE protection schemes like path protection, link protection, and node protection that use backup LSPs to provide sub-50ms failure recovery for critical real-time applications. Local protection schemes that encapsulate the primary LSP within backup tunnels are particularly scalable with fast recovery for link and node failures.
Multi Protocol Label Switching. (by Rahil Reyaz)RAHIL REYAZ
MPLS was developed to address some of the disadvantages of IP and ATM routing. It works by assigning labels to packets at the edge of the network which are then used to forward packets across the core. This label switching allows for faster forwarding than IP routing. MPLS can be used to engineer traffic flows, provide virtual private networks, and transport various layer 2 protocols over an IP or MPLS backbone. While it adds complexity, MPLS improves performance and supports quality of service and network scalability.
1. MPLS simplifies forwarding by introducing label switching which uses a forwarding table and label carried in each packet rather than conventional IP routing based on IP addresses.
2. MPLS establishes label switched paths between routers where each router along the path transmits the packet to the next router by means of a label. Edge routers analyze packets and assign an initial label.
3. The main benefits of MPLS include improved performance, scalability, and traffic engineering capabilities compared to conventional IP routing.
1. MPLS simplifies forwarding by introducing label switching which uses a forwarding table and label carried in each packet rather than conventional IP routing based on IP addresses.
2. MPLS establishes label switched paths between routers where each router along the path transmits the packet to the next router by means of a label. Edge routers analyze packets and assign an initial label.
3. The main benefits of MPLS include improved performance, scalability, and traffic engineering capabilities compared to conventional IP routing.
This slide contains basic concept about MPLS and LDP protocol, according to the latest version of Cisco books(SP and R&S) and i taught it at IRAN TIC company.
i will prepare MPLS_VPN and MPLS_QoS and MPLS_TE later.
MPLS (Multi Protocol Label Switching) is a mechanism for data transport that operates on the data link layer below protocols like IP. It is mainly used to forward IP datagrams and Ethernet traffic. MPLS overcomes limitations of traditional IP routing by bringing the intelligence of routing with the performance of switching, and supports VPNs, QoS, and effective bandwidth management. MPLS works by assigning short fixed-length labels to packets, and routers use the labels stored in forwarding tables to make switching decisions instead of long IP addresses.
MPLS is a packet forwarding technique that can carry any layer 3 protocol. It works by assigning labels to packets at the edge router. Subsequent routers use these labels to forward packets without looking at the layer 3 headers, making forwarding more efficient. MPLS provides benefits like traffic engineering, quality of service, and scalability compared to traditional IP routing. It works by assigning packets to forwarding equivalence classes, assigning labels to these classes, and using label switching to forward packets based on these labels rather than IP routing lookups.
This document provides an overview of MPLS (Multiprotocol Label Switching) including:
- MPLS uses labels instead of IP addresses to forward packets for benefits like decreased routing overhead and support for non-IP protocols.
- Key MPLS terminology includes label-switched routers that forward packets based on labels, edge routers that impose/remove labels, and label switched paths that define the path through the network.
- The MPLS control plane establishes label switched paths and the data plane uses forwarding based on pre-established labels for faster switching compared to IP routing.
MPLS is a forwarding scheme that uses fixed-length labels to simplify packet forwarding. It allows explicit routing and fast restoration from failures. MPLS headers carry labels that are used by routers to forward packets based on forwarding equivalence classes. This enables traffic management and quality of service routing. Local protection techniques like bypass tunnels and label stacking allow MPLS to provide fast restoration by pre-establishing backup label switched paths.
MPLS provides benefits such as supporting multiple applications, decreasing forwarding overhead on core routers, and supporting forwarding of non-IP protocols. MPLS establishes label switched paths using label distribution protocols like LDP to propagate labels between routers so that packets can be forwarded based on a label lookup rather than a routing table lookup at every hop. During convergence after a link failure, routing protocols first reconverge while MPLS convergence involves repopulating forwarding information based on stored label mappings.
The document discusses performance measurements of MPLS traffic engineering and QoS. It provides background on traditional IP routing and its disadvantages, and explains the need for MPLS to address issues like traffic engineering, QoS, and scalability. Key MPLS concepts covered include FEC, LER, LSR, LSP, labels, label switching, label stacking, LIB tables, and the forwarding process. Traditional IP routing is compared to MPLS forwarding.
Multi-Protocol Label Switching (MPLS) allows packets to be forwarded along predetermined paths through a network based on short fixed-length labels rather than long variable-length IP addresses. MPLS is used by carriers and large enterprises to implement traffic engineering, virtual private networks, and quality of service through mechanisms like traffic classification and label switching along label switch paths.
MPLS is a forwarding scheme that uses fixed-length labels to simplify packet forwarding. It allows explicit routing and fast restoration from failures. MPLS labels are inserted into packets at the edge of an MPLS network and used to look up forwarding information by subsequent routers. This allows traffic to be engineered and differentiated services to be provided. Local protection techniques like bypass tunnels and label stacking enable fast restoration from link and node failures.
Overview of the MPLS backbone transmission technology.
MPLS (MultiProtocol Layer Switching) is a layer 2.5 technology that combines the virtues of IP routing and fast layer 2 packet switching.
IP packet forwarding is not suited for high-speed forwarding due to the need to evaluate multiple routes for each IP packet in order to find the optimal route, i.e. the route with the longest prefix match.
However, Internet Protocol routing provides global reachability through the IP address and through IP routing protocols like BGP or OSPF.
Layer 2 packet switching has complementary characteristics in that it does not provide global reachability through globally unique addresses but allows fast packet forwarding in hardware through the use of small and direct layer 2 lookup addresses.
MPLS combines IP routing and layer 2 switching by establishing layer 2 forwarding paths based on routes received through IP routing protocols like BGP or OSPF.
Thus the control plane of an MPLS capable device establishes layer 2 forwarding paths while the data plane then performs packet forwarding, often in hardware.
MPLS is not a layer 2 technology itself, i.e. it does not define a layer 2 protocol but rather makes use of existing layer 2 technologies like Ethernet, ATM or Frame Relay.
Multiprotocol Label Switching, or MPLS, is a networking technology that manages forwarding over private wide area networks by utilizing the shortest path based on "labels," as opposed to network addresses.
its only running on WAN network.
This can only be implemented with any one routing protocol.
Using Label Distribution Protocol.
LDP is a protocol that automatically generates and exchanges labels between routers. Each router will locally generate labels for its prefixes and will then advertise the label values to its neighbors.
MPLS was developed to combine the fast packet forwarding capabilities of ATM with the flexibility of IP by using fixed-length labels to direct data packet through networks. MPLS uses label edge routers to assign labels to packets based on forwarding equivalence classes and distribute labels through protocols like LDP. Core label switching routers use label switching tables to forward packets based on their labels rather than long IP addresses. MPLS enables traffic engineering, QoS, and virtual private networks while maintaining independence from lower layer technologies.
This document provides an overview of Multi-Protocol Label Switching (MPLS) technology. It discusses MPLS fundamentals, components, operations, applications for traffic engineering, virtual private networks, and any transport over MPLS. It also outlines topics like MPLS label distribution, virtual private network models, and future developments in MPLS. The document is intended to guide readers on key concepts in MPLS and provide background for further study.
This document discusses potential security issues related to MPLS networks. It begins by defining some MPLS terminology like Label Distribution Protocol, Label Switched Path, and Label Switching Router. It then explores ideas like an attacker rewriting MPLS labels to redirect traffic or injecting spoofed messages into the Label Distribution Protocol to manipulate label mappings. However, the document notes that actually exploiting these issues against a real telecom backbone would be very difficult or impossible due to network controls and monitoring. The goal is to raise awareness of security considerations for MPLS rather than enable real attacks.
MPLS (Multi-Protocol Label Switching) is introduced as a "Layer 2.5" protocol that sits between traditional Layer 2 and Layer 3 networking. It works by assigning labels to packets at ingress routers and using those labels for fast forwarding decisions without additional routing lookups at subsequent routers. This improves performance over traditional IP routing. MPLS also enables traffic engineering through protocols like RSVP-TE that allow reserving bandwidth on specific paths. Other key MPLS concepts covered are label switching, MPLS signaling protocols, label stacking, pseudowires, VPN services, and fast reroute for improved convergence during failures.
MPLS is a forwarding mechanism that uses labels instead of IP addresses to forward packets. It allows routers to forward based on simple label lookups rather than complex routing lookups. MPLS has benefits like supporting multiple applications and decreasing forwarding overhead on core routers. It has a control plane that exchanges routing information and labels, and a data plane that forwards packets based on labels. Label Switch Routers implement MPLS forwarding by exchanging labels and forwarding packets based on those labels.
MPLS-TE provides fast reroute (FRR) capabilities to minimize traffic loss during network failures. FRR utilizes pre-established backup label switched paths (LSPs) to quickly switch traffic around failures without waiting for IGP convergence. This document describes different MPLS-TE protection schemes like path protection, link protection, and node protection that use backup LSPs to provide sub-50ms failure recovery for critical real-time applications. Local protection schemes that encapsulate the primary LSP within backup tunnels are particularly scalable with fast recovery for link and node failures.
Multi Protocol Label Switching. (by Rahil Reyaz)RAHIL REYAZ
MPLS was developed to address some of the disadvantages of IP and ATM routing. It works by assigning labels to packets at the edge of the network which are then used to forward packets across the core. This label switching allows for faster forwarding than IP routing. MPLS can be used to engineer traffic flows, provide virtual private networks, and transport various layer 2 protocols over an IP or MPLS backbone. While it adds complexity, MPLS improves performance and supports quality of service and network scalability.
1. MPLS simplifies forwarding by introducing label switching which uses a forwarding table and label carried in each packet rather than conventional IP routing based on IP addresses.
2. MPLS establishes label switched paths between routers where each router along the path transmits the packet to the next router by means of a label. Edge routers analyze packets and assign an initial label.
3. The main benefits of MPLS include improved performance, scalability, and traffic engineering capabilities compared to conventional IP routing.
1. MPLS simplifies forwarding by introducing label switching which uses a forwarding table and label carried in each packet rather than conventional IP routing based on IP addresses.
2. MPLS establishes label switched paths between routers where each router along the path transmits the packet to the next router by means of a label. Edge routers analyze packets and assign an initial label.
3. The main benefits of MPLS include improved performance, scalability, and traffic engineering capabilities compared to conventional IP routing.
This slide contains basic concept about MPLS and LDP protocol, according to the latest version of Cisco books(SP and R&S) and i taught it at IRAN TIC company.
i will prepare MPLS_VPN and MPLS_QoS and MPLS_TE later.
MPLS (Multi Protocol Label Switching) is a mechanism for data transport that operates on the data link layer below protocols like IP. It is mainly used to forward IP datagrams and Ethernet traffic. MPLS overcomes limitations of traditional IP routing by bringing the intelligence of routing with the performance of switching, and supports VPNs, QoS, and effective bandwidth management. MPLS works by assigning short fixed-length labels to packets, and routers use the labels stored in forwarding tables to make switching decisions instead of long IP addresses.
MPLS is a packet forwarding technique that can carry any layer 3 protocol. It works by assigning labels to packets at the edge router. Subsequent routers use these labels to forward packets without looking at the layer 3 headers, making forwarding more efficient. MPLS provides benefits like traffic engineering, quality of service, and scalability compared to traditional IP routing. It works by assigning packets to forwarding equivalence classes, assigning labels to these classes, and using label switching to forward packets based on these labels rather than IP routing lookups.
This document provides an overview of MPLS (Multiprotocol Label Switching) including:
- MPLS uses labels instead of IP addresses to forward packets for benefits like decreased routing overhead and support for non-IP protocols.
- Key MPLS terminology includes label-switched routers that forward packets based on labels, edge routers that impose/remove labels, and label switched paths that define the path through the network.
- The MPLS control plane establishes label switched paths and the data plane uses forwarding based on pre-established labels for faster switching compared to IP routing.
MPLS is a forwarding scheme that uses fixed-length labels to simplify packet forwarding. It allows explicit routing and fast restoration from failures. MPLS headers carry labels that are used by routers to forward packets based on forwarding equivalence classes. This enables traffic management and quality of service routing. Local protection techniques like bypass tunnels and label stacking allow MPLS to provide fast restoration by pre-establishing backup label switched paths.
MPLS provides benefits such as supporting multiple applications, decreasing forwarding overhead on core routers, and supporting forwarding of non-IP protocols. MPLS establishes label switched paths using label distribution protocols like LDP to propagate labels between routers so that packets can be forwarded based on a label lookup rather than a routing table lookup at every hop. During convergence after a link failure, routing protocols first reconverge while MPLS convergence involves repopulating forwarding information based on stored label mappings.
The document discusses performance measurements of MPLS traffic engineering and QoS. It provides background on traditional IP routing and its disadvantages, and explains the need for MPLS to address issues like traffic engineering, QoS, and scalability. Key MPLS concepts covered include FEC, LER, LSR, LSP, labels, label switching, label stacking, LIB tables, and the forwarding process. Traditional IP routing is compared to MPLS forwarding.
Multi-Protocol Label Switching (MPLS) allows packets to be forwarded along predetermined paths through a network based on short fixed-length labels rather than long variable-length IP addresses. MPLS is used by carriers and large enterprises to implement traffic engineering, virtual private networks, and quality of service through mechanisms like traffic classification and label switching along label switch paths.
MPLS is a forwarding scheme that uses fixed-length labels to simplify packet forwarding. It allows explicit routing and fast restoration from failures. MPLS labels are inserted into packets at the edge of an MPLS network and used to look up forwarding information by subsequent routers. This allows traffic to be engineered and differentiated services to be provided. Local protection techniques like bypass tunnels and label stacking enable fast restoration from link and node failures.
Overview of the MPLS backbone transmission technology.
MPLS (MultiProtocol Layer Switching) is a layer 2.5 technology that combines the virtues of IP routing and fast layer 2 packet switching.
IP packet forwarding is not suited for high-speed forwarding due to the need to evaluate multiple routes for each IP packet in order to find the optimal route, i.e. the route with the longest prefix match.
However, Internet Protocol routing provides global reachability through the IP address and through IP routing protocols like BGP or OSPF.
Layer 2 packet switching has complementary characteristics in that it does not provide global reachability through globally unique addresses but allows fast packet forwarding in hardware through the use of small and direct layer 2 lookup addresses.
MPLS combines IP routing and layer 2 switching by establishing layer 2 forwarding paths based on routes received through IP routing protocols like BGP or OSPF.
Thus the control plane of an MPLS capable device establishes layer 2 forwarding paths while the data plane then performs packet forwarding, often in hardware.
MPLS is not a layer 2 technology itself, i.e. it does not define a layer 2 protocol but rather makes use of existing layer 2 technologies like Ethernet, ATM or Frame Relay.
Multiprotocol Label Switching, or MPLS, is a networking technology that manages forwarding over private wide area networks by utilizing the shortest path based on "labels," as opposed to network addresses.
its only running on WAN network.
This can only be implemented with any one routing protocol.
Using Label Distribution Protocol.
LDP is a protocol that automatically generates and exchanges labels between routers. Each router will locally generate labels for its prefixes and will then advertise the label values to its neighbors.
MPLS was developed to combine the fast packet forwarding capabilities of ATM with the flexibility of IP by using fixed-length labels to direct data packet through networks. MPLS uses label edge routers to assign labels to packets based on forwarding equivalence classes and distribute labels through protocols like LDP. Core label switching routers use label switching tables to forward packets based on their labels rather than long IP addresses. MPLS enables traffic engineering, QoS, and virtual private networks while maintaining independence from lower layer technologies.
This document provides an overview of Multi-Protocol Label Switching (MPLS) technology. It discusses MPLS fundamentals, components, operations, applications for traffic engineering, virtual private networks, and any transport over MPLS. It also outlines topics like MPLS label distribution, virtual private network models, and future developments in MPLS. The document is intended to guide readers on key concepts in MPLS and provide background for further study.
This document discusses potential security issues related to MPLS networks. It begins by defining some MPLS terminology like Label Distribution Protocol, Label Switched Path, and Label Switching Router. It then explores ideas like an attacker rewriting MPLS labels to redirect traffic or injecting spoofed messages into the Label Distribution Protocol to manipulate label mappings. However, the document notes that actually exploiting these issues against a real telecom backbone would be very difficult or impossible due to network controls and monitoring. The goal is to raise awareness of security considerations for MPLS rather than enable real attacks.
7. What is “Label Switching”?
• Traditionally each router looks “inside” the
packet to determine it’s destination
• Opening the envelope at every sorting office
to work out where it needs to go = SLOW!
8. What is “Label Switching?”
• In MPLS routers have pre-defined label-
switched paths in their routing table
• They already know the best route to varying
destinations
9. What is “Label Switching?”
• Router 1 (PE) adds a shipping label to the
packet
10. What is “Label Switching?”
• The rest of the routers handle the packet with
this label according to their LSP
11. What is “Label Switching?”
• The final router pops the label and delivers as
normal
15. Really quick other stuff – MPLS VPN
• Switch in the cloud (L2 - VPLS)
– Offers a long Ethernet cable
– VPN spanning between sites
– Time critical applications (VoIP, Video)
• L3 VPNs (VPRN)
– VRFs for each customer
– CE and PE peer and exchange routes
– Complex network layout
– Needs MP-BGP
MPLS – Multi Protocol Label Switching is a protocol that service providers run within the core network to speed up routing and allow QoS more easily.
MPLS doesn’t happily fit in either the Data-Link layer, nor the Network layer. It provides enhanced L2 features, but isn’t quite at L3. This is why we say it’s at layer 2.5. It was originally designed to speed up the routing of packets across a service providers network (cloud) by altering the way that the routers examine the packets and make forwarding decisions. However with the development of switching and routing technology (ASICs) these days it’s main use is to provide VPNs and other traffic engineering.
There are many benefits to using MPLS. Lets look at interface independence and scalability.
Before MPLS we would usually connect sites together using some sort of WAN link like Frame Relay circuits. Let’s say we have a site in London, and another in Sheffield. Not too bad – just two sites to connect to each other. But what happens if we try and scale this model? Let’s add Leeds, Edinburgh and Glasgow. Now we have all our sites connecting to each other. What happens if we lose one of our links? Say between Sheffield and Leeds. That means that Leeds, Glasgow and Edinburgh are all offline until the link is restored.
Lets take the same 5 sites and connect them to an MPLS network instead. Now none of the sites is dependent upon another for it’s connection and instead we have a fully meshed one to many relationship. As the service provider gives you virtual circuits between each of your sites each can keep working independently of one another.
Taking our same mesh – MPLS adds another benefit: Interface independence. Lets say that our Leeds site only has 5 employees based there. We don’t want to be shelling out for a 100Mbps Ethernet circuit when a simple ADSL connection will do. Well, MPLS allows you to do this.
In traditional IP networks each router makes a forwarding decision based upon the L3 destination header of each packet. It has to look at every packet in detail! Our poor router feels like a washing machine, constantly rinsing and repeating – not only that but doing this slows it down. It’s like you are sending a letter from New York to London and every sorting office had to open the envelope, look at the address, repackage the letter and send it on to the next sorting office. BORING! Oh, and slow. MPLS gets around this problem by enclosing your letter in an envelope with the destination on the front.
Instead of having to examine the packet, each router now just looks at the label and sends the packet on it’s way according to the pre-defined routes (Label Switched Paths) in it’s VRF. This operation is similar in both logic and speed as to how L2 switches make forwarding decisions. This has the net result of speeding up the whole packet transit.
The router at the “edge” of the service providers network does the label popping, and imposition. So traffic coming into this router will be examined and given a label; whereas traffic exiting at this router will have the label “popped” off, and forwarded as a normal IP packet.
The routers in the middle already know the best route to the destination label, so all they need to do is look at the envelope and read it’s address, then forward it out of the correct interface on it’s onward journey.
And as already mentioned, the PE at the other end pops off the label and delivers the packet as normal.
Looking at the mesh we used earlier we’ve got all these sites connected via their own technology. Each of these technologies runs a different protocol over the top. MPLS is able to handle this without an issue, whereas older technologies would have to run the same protocol throughout the network.
The “P” Routers are at the core of the MPLS network infrastructure. Also called LSR’s = Label Switching Routers.
The “PE” routers are the provider edge routers. So called, because they sit at the edge of the provider’s network. It’s important to remember that there are many PE’s, but you will typically only interface with one.
Last up we have the CE router. CE is Customer Edge, so called because they sit at the edge of your network as the customer. Typically the peering between the PE and CE is done via a routing protocol – most popular is BGP (Border Gateway Protocol). The customers’ network administrator will program their router with an IP address facing the PE. This is usually a /30 for the purposes of the link.
VPLS = Virtual Private LAN Service and allows you to run Layer 2 across multiple sites, and extend your VLAN tagging across the cloud to your remote site.
VPRN = Virtual Private Routed Network is the Layer 3 version of VPLS. This allows SP’s to use the same physical P router for many customers, by segregating their traffic into different VRF’s.
MP-BGP = Multiprotocol BGP