This document provides an overview of MPLS (Multi-Protocol Label Switching) concepts including label switching, label allocation, and label forwarding. It discusses MPLS label structure, label encapsulation, label spaces, label forwarding entries, and label distribution protocols. The key topics covered are:
1) MPLS was developed to integrate connectionless IP networks with connection-oriented ATM networks for traffic engineering and QoS purposes. It works by encapsulating packets with labels and performing label switching instead of IP forwarding.
2) MPLS uses labels added to packet headers to forward packets. Label allocation can be downstream-on-demand or unsolicited. Label distribution protocols like LDP are used to establish label
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.
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.
“MPLS is that it’s a technique, not a service.”
The fundamental concept behind MPLS is that of labeling packets. In a traditional routed IP network,
each router makes an independent forwarding decision for each packet based solely on the packet’s
network-layer header. Thus, every time a packet arrives at a router, the router has to “think through”
where to send the packet next.
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.
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.
“MPLS is that it’s a technique, not a service.”
The fundamental concept behind MPLS is that of labeling packets. In a traditional routed IP network,
each router makes an independent forwarding decision for each packet based solely on the packet’s
network-layer header. Thus, every time a packet arrives at a router, the router has to “think through”
where to send the packet next.
An introduction to MPLS networks and applicationsShawn Zandi
Multiprotocol Label Switching (MPLS) provides label switched path to deliver packets in networks. This is an introduction course to understand different terminologies and concepts associated with MPLS.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Elevating Tactical DDD Patterns Through Object CalisthenicsDorra BARTAGUIZ
After immersing yourself in the blue book and its red counterpart, attending DDD-focused conferences, and applying tactical patterns, you're left with a crucial question: How do I ensure my design is effective? Tactical patterns within Domain-Driven Design (DDD) serve as guiding principles for creating clear and manageable domain models. However, achieving success with these patterns requires additional guidance. Interestingly, we've observed that a set of constraints initially designed for training purposes remarkably aligns with effective pattern implementation, offering a more ‘mechanical’ approach. Let's explore together how Object Calisthenics can elevate the design of your tactical DDD patterns, offering concrete help for those venturing into DDD for the first time!
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
Accelerate your Kubernetes clusters with Varnish Caching
ODC010001 MPLS Basic Knowledge ISSUE1.5.ppt
1. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved
www.huawei.com
Internal
ODC010001 MPLS Basic
Knowledge
ISSUE 1.5
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The course introduce the basic concept
of MPLS, including MPLS label, MPLS
switching, MPLS label allocating.
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Upon completion of this course, you
will be able to:
Describe the switching process of
MPLS, the method to allocate and
control the label.
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Chapter 1 MPLS Overview
Chapter 2 Label and Label Stack
Chapter 3 Label Forwarding and Allocation
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MPLS
MPLS——Multi-Protocol Label Switching
Multi-Protocol
Support multiple Layer-3 protocols, such as IP, IPv6, IPX,
SNA
Label Switching
Label packets, and replace IP forwarding with label
switching
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Origin: To Integrate IP with ATM
Connectionless
control plane
Connectionless
forwarding plane
IP
Connection-oriented
control plane
Connection-oriented
forwarding plane
ATM
Connectionless
control plane
Connection-oriented
forwarding plane
MPLS
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Connection-oriented Features
Connectionless: packet route
Path 1 = S1, S2, S6, S8
Path 2 = S1, S4, S7, S8
The data reach their destination
out of order along different
paths
connection-oriented: cell switching
VC = S1, S4, S7, S8
The data reach their destination in
order along the same connection
Fixed time delay, easy to control
Connection types: PVC SVC
S2 S6
S4 S7
S3 S5
S1 S8
1
1
1
2 2
2
S2 S6
S4 S7
VC
S1 S8
S3 S5
8. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 7
Traditional IP Forwarding
IP header is parsed at each hop, resulting in low efficiency.
It is hard to deploy QoS and the efficiency is rather low.
All routers are expected to know all routes in the entire network.
Parse IP header
mapped to next hop
Parse IP header
mapped to next hop
Parse IP header
mapped to next hop
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Virtual Channel Connection (VCC)
VC
switching
VC
switching
NNI NNI
VPI = 2
VCI = 44
VPI = 1
VCI = 1
VPI = 26
VCI = 44
VPI = 20
VCI = 30
UNI
UNI
ATM Switching Process
Connection-oriented, N2 problem
Routing depending on link layer, based on VPI/VCI or label
Ensure QoS and real-time service
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Technology Combining the Advantages of ATM and IP
+ X
R = X
Router ATM switch MPLS
Router
MPLS——multi-protocol label switching
Layer 3 routing – scalable and flexible
Layer 2 switching – High reliability and traffic engineering
management
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Core LSR
Basic Working Process of MPLS
IP IP L1 IP L2 IP L3 IP
Traditional IP
forwarding
Traditional
IP forwarding Label forwarding
Edge LSR Edge LSR
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MPLS Advantages
Replace IP header with short and fixed-length labels as
forwarding basis to improve forwarding speed
Better integrate IP with ATM
Provide value-added service without prejudice to efficiency:
VPN
Traffic engineering
QOS
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Exercise-1
1. What is MPLS?
2. Describe the core function of MPLS
3. Describe LER, LSR and LSP
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Chapter 1 MPLS Overview
Chapter 2 Label and Label Stack
Chapter 3 Label Forwarding and Allocation
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MPLS Encapsulation Format and Label
MPLS header
Layer 2
header
IP header Data
Label S
EXP TTL
20
0 23 24 31
32 bits
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Label Values
Special use and reserved range
− 0: IPv4 explicit null, label stack must be popped
− 1: Router alert, local processing operation
− 2: IPv6 explicit null, label stack must be popped
− 3: Implicit null, triggers label stack pop, overrides label swap
− 4 to 15: reserved
General use range
− 16 to 1,048,575
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Label Position in Packet
Ethernet header
/PPP header Label Layer-3 data
Ethernet
/SONET
/SDH packet
ATM header Label Layer-3 data
Frame mode
ATM packet
Cell mode
ATM packet VPI/VCI Layer-3 data
Two types of MPLS encapsulation for ATM and FR:
shim encapsulation: similar to other link layers
Cell mode: VC (VPI/VCI for ATM, DLCI for FR) is directly
used as the label
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Label Spaces and Identifiers
Label space is a set of interface-specific or platform-wide labels
Platform-wide: One pool of labels is shared across all interfaces
Per-interface: Label values can be reused on each interface
Label space
Label space ID—Zero for platform-wide label space (2 octets)
For example, 192.168.1.1:0 (platform-wide), 192.168.1.1:5 (per-interface)
MPLS based frame mode use Platform-wide label space, such as IP,
Ethernet.
MPLS based cell mode use Per-interface label space, such as ATM.
20. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 19
MPLS TTL Processing
Regard the entire MPLS domain as one hop
IP TTL --
MPLS TTL＝255 MPLS TTL -- IP TTL --
Ingress LER LSR Egress LER
Include MPLS TTL in IP TTL
IP TTL --
MPLS TTL＝IP TTL MPLS TTL --
MPLS TTL --
IP TTL＝MPLS TTL
Ingress LER LSR Egress LER
21. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 20
LSP Loop Detection
Path looping shall be avoided even in setting up LSP within the
MPLS domain.
LSP path looping can be avoided in two ways:
Maximum hop number;
Path vector
LSRA LSRB LSRC LSRX
1 2 3 32
LSRA LSRB
LSRA
LSRC
LSRA,LSRB
LSRA,LSRB…..
LSRA,LSRB…..LSRC
22. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 21
Label Stack
Theoretically, label stack enables limitless nesting to provide
infinite service support. This is simply the greatest advantage
of MPLS technology.
MPLS
header
Layer2
header IP header Data
MPLS
header
23. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 22
Exercise-2
1. Describe MPLS label structure
2. Describe label position with different encapsulation mode
3. Describe two LSP loop detection methods
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Chapter 1 MPLS Overview
Chapter 2 Label and Label Stack
Chapter 3 Label Forwarding and Allocation
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Basic Concepts of Label Forwarding
FEC (Forwarding Equivalence Class): Import the packets with
identical characteristics into the same LSP
NHLFE (Next Hop Label Forwarding Entry): Describe label
operations
next hop
label operation types: push/pop/swap/null
Link layer encapsulation types
FTN (FEC to NHLFE): Map FEC to NHLFE
ILM (Incoming Label Map): Map MPLS label to NHLFE
26. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 25
Label Forwarding
The traditional routing protocol and Label Distribution Protocol (LDP) serve to create routing table
and label mapping table (FEC-Label mapping) in each LSR for FECs with service requirement,
i.e. create LSP successfully.
Ingress LER receives a packet, determines the FEC that the packet belongs to, and label the
packet
In MPLS domain, packets are forwarded in accordance with labels and label forwarding table via
the forwarding unit
Egress LER removes the label and continues forwarding the packet
Parse IP header
FEC bound with LSP
FTN->NHLFE
ILM->NHLFE
ILM->NHLFE
Parse IP header
distribute FEC
mapped to next hop
ILM->NHLFE
Ingress LER LSR LSR Egress LER
Label operation: push
Label operation: swap Label operation: swap
label operation: pop
A B C D
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NHLFE
A:
…
Add label L1
E1
B
10.0.1.0/24
Others
Label operation
Transmitting interface
next hop
NHLFE
FEC
…
Remove the previous label and add L2
E1
C
L1
Others
label operation
Transmitting interface
Next hop
NHLFE
Ingress
label
B:
…
Remove the previous label and add L3
D
L2
Others
Label operation
Next hop
NHLFE
Ingress
label
C:
E1
Transmitting interface
28. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 27
Penultimate Hop Popping (PHP)
The label at the outmost layer does not make any sense to the last hop. Thus, it
is advisable to pop the label at the last hop but one to ease the burden of the last
hop.
If there is only one layer of label, the last hop will perform IP forwarding directly;
otherwise, it will perform the internal label forwarding.
Parse IP header
Distribute FEC
Mapped to next hop
Label operation: pop
Parse IP header
FEC bound with LSP
FTN->NHLFE ILM->NHLFE ILM->NHLFE
Ingress LER LSR LSR Egress LER
Label operation: push
Label operation: swap
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Creating LSP
LSP drive modes:
Driven by stream: incoming packets drive LSP creation
Driven by topology: topology information (route) drives LSP creation
Driven by application: application (like QoS) drives LSP creation
Signaling protocol is used to distribute labels between LSRs and
establish LSP:
LDP: Label Distribution Protocol
CR-LDP: Constrained Route LDP
RSVP-TE
MP-BGP
PIM
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Several Issues Concerning Label Distribution
Label allocation mode
DoD : downstream-on-demand
DU: downstream unsolicited
Label control mode
Ordered
Independent
Label retention mode
Conservative retention mode : upon receiving a label, if there is no
route destined for corresponding FEC, discard the label.
Liberal mode: upon receiving a label, if there is no route destined for
the corresponding FEC, hold the label for later use.
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Label Allocation Mode: DoD
Upstream Downstream
The upstream LSR sends a label request (containing FEC description
information) to the downstream LSR.
The downstream LSR allocates a label to this FEC and feeds back the bound
label to the upstream LSR via the label mapping message.
171.68.10.0/24
171.68.40.0/24
LSR1 LSR2 LSR3
请求到目的地址
171.68.10/24 的标签
Requesting labels destined
for 171.68.10.0/24 的标签
Requesting labels
destined for 171.68.10.0/24
分配到171.68.10/24
的标签为
20
Label 20 is allocated
to 171.68.10.0/24
分配到171.68.10/24
的标签为18
Label 18 is
allocated to
171.68.10.0/24
Route triggering
32. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 31
Label Allocation Mode: DU
Upstream
Downstream
Route
triggering
Once the LDP session is set up successfully, the downstream LSR will
initiatively advertise the label mapping message to its upstream LSR.
The upstream router will save the label in the label mapping table.
到171.68.10/24
可以使用标签 20
Label 20 can be used
to reach
171.68.10.0/24
171.68.10.0/24
171.68.40.0/24
Label 18 can be used
to reach
171.68.10.0/24
33. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 32
Label Control Mode: Ordered
Not until it receives a label mapping message from its downstream
LSP will it send the message upstream
Upstream Downstream
DOD+ Ordered
Upstream Downstream
DU+ Ordered
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Label Control Mode: Independent
Upstream Downstream
Whether it receives a label mapping message from its downstream LSR, it will
send upstream a label mapping message immediately.
Upstream Downstream
DOD+ independent
DU+ independent
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Label Retention: Conservative Retention Mode
An LSR stores only the labels received from next-hop LSRs; all
other labels are ignored.
LSR1 LSR2 LSR3 LSR4
LSR5
172.16.2/24
mapping
label 20
mapping
label 30
mapping
label 17
mapping
label 16
Drop
36. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 35
Label Retention: Liberal Retention Mode
LSR1 LSR2 LSR3 LSR4
LSR5
172.16.2/24
mapping
label 20
mapping
label 30
mapping
label 17
mapping
label 16
store
Every LSR stores the received label in its LIB, even when the label
is not received from a next-hop LSR.
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Common Collocation 1: DoD + Ordered + Conservative
Upstream Downstream
It is relatively easy to control the use of labels and the creation of LSPs
ATM/FR frame mode can only use DoD
38. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 37
Common Collocation 2: DU + Ordered + Liberal
Upstream Downstream
A waste of label resources
Useless LSPs would be created
Label merge is required at branches
LSPs can be set up quickly and reliably
39. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 38
Label Forwarding Table
IN interface IN label Prefix/MASK OUT interface
(next hop)
OUT label
Serial0 50 10.1.1.0/24 Eth0（3.3.3.3） 80
Serial1 51 10.1.1.0/24 Eth0（3.3.3.3） 80
Serial1 62 70.1.2.0/24 Eth0（3.3.3.3） 52
Serial1 52 20.1.2.0/24 Eth1（4.4.4.4） 52
Serial2 77 30.1.2.0/24 Serial3（5.5.5.5) 3（pop）
The “in” and “out” is correspond to the label swap，not the label
distribution.
The in label is that I distribute to the others, I will not put it to
the packet
The out label is the others distribute to me, I will put it to the
packet
40. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 39
Exercise-3
1. Describe MPLS label switching process
2. Describe MPLS label distribution work mode: allocation, control
and retention.
41. HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 40
Grasp the basic concepts and working
process of MPLS
Grasp label allocation and distribution
Summary
