In this presentation, RAD’s Chief Scientist, Dr. Yaakov Stein, reviews the evolution of Ethernet OAM tools and practices and discusses the drivers for their developm
This third webinar discusses the fundamentals of LTE Carriers and how LTE mobiles communicate with the network including what factors affect performance.
Determine the required delivery characteristics of a packet stream and how a Traffic Management (TM) module can offload compute-intensive tasks. Hear more about the latest innovations in both DPI & TM solutions.
LTE network: How it all comes together architecture technical posterDavid Swift
Mobile network operators that want to deploy LTE now want to do so on their own terms. They want to roll out ultrafast mobile broadband safe in the knowledge that one vendor’s solution will work efficiently with another, while delivering the high level of service that subscribers expect. A standards-based network will ensure the goal is met and help drive down cost for operators, but understanding how to pull it all together can be a challenge. So how does it all come together?
This third webinar discusses the fundamentals of LTE Carriers and how LTE mobiles communicate with the network including what factors affect performance.
Determine the required delivery characteristics of a packet stream and how a Traffic Management (TM) module can offload compute-intensive tasks. Hear more about the latest innovations in both DPI & TM solutions.
LTE network: How it all comes together architecture technical posterDavid Swift
Mobile network operators that want to deploy LTE now want to do so on their own terms. They want to roll out ultrafast mobile broadband safe in the knowledge that one vendor’s solution will work efficiently with another, while delivering the high level of service that subscribers expect. A standards-based network will ensure the goal is met and help drive down cost for operators, but understanding how to pull it all together can be a challenge. So how does it all come together?
The important goal of this thesis is represented as demonstrating a self-organising based process for current versions of heterogeneous LTE-Advanced networks to simultaneously improve both quality of service and ability. The main index terms of this research could be exhibited as: SON; LTE-A, HetNets; Femtocell; Interference, Multi-Layer; Handover, Access Control; Power Control, eICIC. The self-organizing method of this research is described as the primary goal, to be got through the following targets: ThesisScientist.com
What LTE Parameters need to be Dimensioned and OptimizedHoracio Guillen
How to Dimension user Traffic in 4G networks
What is the best LTE Configuration
Spectrum analysis for LTE System
MIMO: What is real, What is Wishful thinking
LTE Measurements what they mean and how they are used
How to consider Overhead in LTE Dimensioning and What is the impact
How to take into account customer experience when Designing a Wireless Network
VoLTE Service Monitoring - VoLTE Voice CallJose Gonzalez
There is currently no accepted standard for the measurement or monitoring of VoLTE Services, even though we believe that this is vital to assure the quality and reliability of such services - and to establish a framework for reliable comparison across implementations.
To this end Ascom has defined a formal definition and implementation strategy to help the Operations team solve a range of challenges, including issues related to EPC, IMS and the Application Server. We will describe this solution in a number of short articles.
This article describes the architecture of our solution and the VoLTE Voice Call test case.
There is currently no accepted standard for the measurement or monitoring of RCS Services, even though we believe that this is vital to assure the quality and reliability of such services -and to establish a framework for reliable comparison across implementations.
To this end Ascom has defined a formal definition and implementation strategy to help the Operations team solve a range of challenges, including issues related to EPC, IMS and the Application Server.
We will describe this solution in a number of short articles. This article describes the 1-to-1 Chat test case.
The important goal of this thesis is represented as demonstrating a self-organising based process for current versions of heterogeneous LTE-Advanced networks to simultaneously improve both quality of service and ability. The main index terms of this research could be exhibited as: SON; LTE-A, HetNets; Femtocell; Interference, Multi-Layer; Handover, Access Control; Power Control, eICIC. The self-organizing method of this research is described as the primary goal, to be got through the following targets: ThesisScientist.com
What LTE Parameters need to be Dimensioned and OptimizedHoracio Guillen
How to Dimension user Traffic in 4G networks
What is the best LTE Configuration
Spectrum analysis for LTE System
MIMO: What is real, What is Wishful thinking
LTE Measurements what they mean and how they are used
How to consider Overhead in LTE Dimensioning and What is the impact
How to take into account customer experience when Designing a Wireless Network
VoLTE Service Monitoring - VoLTE Voice CallJose Gonzalez
There is currently no accepted standard for the measurement or monitoring of VoLTE Services, even though we believe that this is vital to assure the quality and reliability of such services - and to establish a framework for reliable comparison across implementations.
To this end Ascom has defined a formal definition and implementation strategy to help the Operations team solve a range of challenges, including issues related to EPC, IMS and the Application Server. We will describe this solution in a number of short articles.
This article describes the architecture of our solution and the VoLTE Voice Call test case.
There is currently no accepted standard for the measurement or monitoring of RCS Services, even though we believe that this is vital to assure the quality and reliability of such services -and to establish a framework for reliable comparison across implementations.
To this end Ascom has defined a formal definition and implementation strategy to help the Operations team solve a range of challenges, including issues related to EPC, IMS and the Application Server.
We will describe this solution in a number of short articles. This article describes the 1-to-1 Chat test case.
Assuring Superior VNF Performance at the Network EdgeADVA
At GEN15 we’re showcasing how communication service providers can integrate NFV-centric services with existing operational processes. This is a joint demonstration with Time Warner Cable Business Class and Juniper Networks.
ZTE COMMUNICATIONS No.2 2016 : Optical wireless communicationsSitha Sok
ZTE COMMUNICATIONS No.2 2016
Fresh off the Press! The April issue focuses on optical wireless communications. Harald Hass, "the father of Li-Fi", and his student contributed to this special issue.
Passive infrastructure of FTTH networks: an overviewLuc De Heyn
Presentation of the FTTH Council webinar on September 2014. A general introduction to FTTH passive infrastructure and a view on the latest trends.
Speaker: Raf Meersman, CEO of Comsof
More info on planning & design of FTTH infrastructure: http://www.fiberplanit.com
Quality of Service at the Internet Engineering Task ForceJohn Loughney
"Quality of Service at the Internet Engineering Task Force" Workshop on "End-to-End Quality of Service. What is it? How do we get it?" Geneva, 1-3 October 2003.
ZTE TECHNOLOGIES No.3 2016 - Special topic: Big VideoSitha Sok
Special Topic
- The Road to Big Video Revolution
- PSVN: The Ultimate Path to Video Transmission Network
- Big Video Best View
- Promising CDN in the Big Video Era
Microwave backhaul gets a boost with multibandSitha Sok
Is there a spectrum shortage? The answer to the question is both yes and no; in some locations spectrum is severely congested, while in other places it is highly underutilized
Emerging Technologies of Future Multimedia Coding, Analysis and TransmissionSitha Sok
Emerging Technologies of Future Multimedia Coding, Analysis and Transmission.
Overview of the Second Generation AVS Video Coding Standard (AVS2).
An Introduction to High Efficiency Video Coding Range Extensions.
Multi⁃Layer Extension of the High Efficiency Video Coding (HEVC) Standard
International Journal of Broadband Cellular Communication
primary goal of this journal is to facilitate the scientific communication between academicians and industries and to make sufficient contribution towards ever changing technology. Journals published original, high quality papers that are peer-reviewed by our expert editorial team to ensure only good quality papers are published.
Descripcion de la tecnologia y sistemas de luz para transmitir señales
Sistemas de transmision por fibra optica, equipos de fibra optica para transmision inalambrica
Presentation by Kevin Smith, Vodafone & Chair ETSI NGP (Next Generation Protocols) at the URLLC 2017 conference on Nov. 14, 2017.
*** Shared with Permission ***
VoIP Monitoring and Analysis - Still Top of Mind in Network Performance Monit...Savvius, Inc
With over 10 years of deployment history, VoIP is the primary voice solution for just about every company in existence - large, medium, or small. But even with all that history, recent research from TRAC shows that VoIP is still the number one IT initiative impacting network performance. And with the growth of 802.11 and Wi-Fi enabled smart phones, the use of voice over Wi-Fi (VoFi) promises to increase the volume of VoIP traffic even more. Analyzing VoIP traffic alone is not enough. VoIP analysis must be part of your overall network performance analysis. After all, VoIP is just another data type on your network, and according to TRAC, it is impacting your network performance, so you must monitor and analyze the network as a whole, including voice and video over IP. Join us to see how easy it is to capture and analyze voice, video, and data traffic simultaneously, allowing you to pinpoint the impact of each data type on your overall network performance.
Link labs LTE-M NB-IOT Hype Webinar slidesBrian Ray
Join us as Link Labs VP of Business Development and Cellular IoT Product Director, Glenn Schatz, discusses common misconceptions about LTE Cat-M1 and Cat-NB1 (NB-IoT), as well as how business and product leaders can use these transformative technologies to deliver value to their customers, while avoiding some of the pitfalls companies face when embarking on this journey.
In this Webinar we will cover:
What are the key features and benefits of LTE Cat-M1 and NB-IoT?
What is the state of devices and network availability today?
How do the various low-power modes work (PSM, eDRX, and vendor-specific), and how can they be used in my application?
What are some of the risks and challenges of developing a product with one of these technologies?
How much do these devices cost? What do the data plans look like?
What is in store for the future with 2G and 3G sunsets (both CDMA and GSM) and the emergence of 5G?
Scalable Service-Oriented Middleware over IPDai Yang
ABSTRACT
Due to the increased amount of communication in cars, a reliable and easy to use middleware system for automotive applications becomes a popular research field. In this paper, we review a recent approach: the Scalable Service-Oriented Middleware over IP (SOME/IP). We present current tech- nologies and how SOME/IP differs from them. We point out how SOME/IP is ordered into the ISO/OSI layer model and discuss its service orientation. We also present the ad- vantages and disadvantages of SOME/IP. In the end, we analyze its timing behavior and whether it is suitable for automotive software or not.
Robust Cyber Security for Power UtilitiesNir Cohen
The security of critical networks is at the center of attention of industry and government regulators alike. Check Point and RAD offer a joint end-to-end cyber security solution that protects any utility operational technology (OT) network by eliminating RTU and SCADA equipment vulnerabilities, as well as defends against cyber-attacks on the network’s control and data planes. This solution brief explains how the joint solution enables compliance with NERC-CIP directives, provides deep visibility and control of ICS/SCADA communications, and allows secure remote access into OT networks.
Replacing end-of-life PDH/SDH/SONET multiplexers in critical infrastructure communications. Learn how to deal with legacy equipment obsolescence and leased line service termination by Telcos, while preparing for smart applications and new packet services.
V cpe deployment-best-practices-presentationNir Cohen
A review of the various vCPE implementation options available for service providers and the factors that should be considered to avoid pitfalls and ensure optimal results.
NERC-CIP’s most recent release, version 5, focuses primarily on BES substations and their critical Cyber Assets (CA), by establishing an Electronic Security Perimeter (ESP) around the substation’s control system. RAD’s Megaplex, a major building block in RAD’s Service Assured Networking (SAN) solutions for power utilities, is strategically located to manage all electronic access to the substation and the cyber assets within it from external and internal attacks.
This paper reviews Megaplex’ 3-tier ESP protection and outlines how it helps power utilities boost their compliance with NERC CIP 005 and 007 requirements
Distributed NFV: Ensuring that the Benefits of Virtualization Exceed the CostsNir Cohen
Dr. Yuri Gittik is taking a closer look at the different approaches to implement NFV solutions is carrier networks, the advantages and disadvantages of each approach and how these approaches are affecting the implementation costs.
As SDH/SONET networks are being phased out, power utilities are starting to migrate to future-proof packet networks. This presentation reviews and compares Carrier Ethernet, MPLS and MPLS-TP to help power utilities determine which alternative offers the best fit for the operational needs of their mission-critical applications.
Time distribution strategies in cellular networksNir Cohen
This paper reviews the various methodologies currently available for ensuring Time of Day (ToD) synchronization in cellular networks. It also introduces RAD’s revolutionary Distributed GMTM scheme, designed to deliver superb ToD accuracy at a lower cost in LTE and small cell networks, by bringing Grandmaster functionality closer to the base station in a small form factor device.
This paper presents a brief overview of today’s mobile backhaul market, outlines the unique challenges facing mobile operators and backhaul transport providers, and suggests strategies for improving network performance and coverage. Key emphasis is on the OAM, resiliency, Quality of Service (QoS) and timing technologies required for cost-efficient backhaul of 2G/3G/4G/LTE and small cells traffic.
This presentation reviews the various tools that carrier-grade Ethernet offers to meet the performance required from the ICT network and discusses strategies for the transition to Smart Grid communications
Carrier grade ethernet for power utilities - solution paperNir Cohen
This paper reviews the various tools that carrier-grade Ethernet offers to meet the performance required from the ICT network and discusses strategies for the transition to Smart Grid communications
A presentation given by RAD’s CTO, Dr. Yaakov Stein, at the 2012 MPLS and Ethernet World Congress. The presentation compares the two technologies in ten critical categories and grades them on suitability, coverage and maturity
There is a pressing need to distribute accurate timing, i.e., frequency and/or Time of Day (ToD), across Packet Switched Networks (PSNs) for applications such as cellular backhaul. This paper reviews the main issues involved in timing over packet (ToP) demarcation and provides best practices for ToP demarcation and performance monitoring.
A review of current trends and challenges in the Carrier Ethernet services market, various deployment strategies adopted by service providers and their effects on network access planning
Teleprotection signals from protective relays are among the most critical data transmitted across utility networks, as they help manage the power grid load, as well as to protect equipment within the power network from severe damages resulting from faulty HV lines. By enabling load-sharing, grid adjustments and immediate fault clearance, Teleprotection has a decisive role in ensuring uninterrupted power supply and therefore requires special attention with regards to network performance and reliability. Specifically, protection commands must be assured immediate delivery when problems are detected, so that faulty equipment can be disconnected before causing a system-wide damage.
Ce the cio perspective part iii v2 1 9-6-11Nir Cohen
This is the third presentation out of 3 on Slideshare reviewing the enterprise needs, issues and considerations from WAN services from CIO point of view. This presentation series is for CIOs and the providers that offer such services. All you need to know about carrier Ethernet service levels and SLAs – what matters to the users and what a service provider should offer.
Part I – why chose carrier Ethernet WAN services
Part II – Service levels and SLA
Part III – Ethernet and IP VPNs – when to use each
Ce the cio perspective part ii v2 3 21-6-11Nir Cohen
This is the second presentation out of 3 on Slideshare reviewing the enterprise needs, issues and considerations from WAN services from CIO point of view. This presentation series is for CIOs and the providers that offer such services. All you need to know about carrier Ethernet service levels and SLAs – what matters to the users and what a service provider should offer.
Part I – why chose carrier Ethernet WAN services
Part II – Service levels and SLA
Part III – Ethernet and IP VPNs – when to use each
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
Generating a custom Ruby SDK for your web service or Rails API using Smithyg2nightmarescribd
Have you ever wanted a Ruby client API to communicate with your web service? Smithy is a protocol-agnostic language for defining services and SDKs. Smithy Ruby is an implementation of Smithy that generates a Ruby SDK using a Smithy model. In this talk, we will explore Smithy and Smithy Ruby to learn how to generate custom feature-rich SDKs that can communicate with any web service, such as a Rails JSON API.
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.
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.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Connector Corner: Automate dynamic content and events by pushing a buttonDianaGray10
Here is something new! In our next Connector Corner webinar, we will demonstrate how you can use a single workflow to:
Create a campaign using Mailchimp with merge tags/fields
Send an interactive Slack channel message (using buttons)
Have the message received by managers and peers along with a test email for review
But there’s more:
In a second workflow supporting the same use case, you’ll see:
Your campaign sent to target colleagues for approval
If the “Approve” button is clicked, a Jira/Zendesk ticket is created for the marketing design team
But—if the “Reject” button is pushed, colleagues will be alerted via Slack message
Join us to learn more about this new, human-in-the-loop capability, brought to you by Integration Service connectors.
And...
Speakers:
Akshay Agnihotri, Product Manager
Charlie Greenberg, Host
2. Why do we pay for services ?
Generally good (and frequently much better than toll quality)
voice service is available free of charge (Skype, Fring, Nimbuzz…)
So why does anyone pay for voice services ?
Similarly, one can get free
• (WiFi) Internet access
• Email boxes
• File storage and sharing
• Web hosting
• Software services
So why pay ?
OAM: Application-driven Evolution Slide 2
3. Paying for QoS
The simple answer is that one doesn’t pay for the
service, one pays for Quality of Service guarantees
In our voice model:
price
toll quality
with mobility
QoS
BE
But what does QoS mean and why are we willing to pay
for it ?
To explain, we need to review some history
OAM: Application-driven Evolution Slide 3
4. Father of the telephone
Everyone knows that the father of the telephone was
Alexander Graham Bell (along with his assistant Mr.
Watson)
But Bell did not invent the telephone network
Bell and Watson sold pairs of phones to customers
The father of the telephone network was Theodore Vail
OAM: Application-driven Evolution Slide 4
5. Theodore Vail
Theodore Who?
• Son of Alfred Vail (Morse’s coworker)
• Ex-General Superintendent of US Railway Mail Service
• First general manager of Bell Telephone
• Father of the PSTN
Why is he so important?
• Organized PSTN
• Established principle of reinvestment in R&D
• Established Bell Telephones IPR division
• Executed merger with Western Union to form AT&T
• Solved the main technological problems
Use of copper wire
Use of twisted pairs
• Organized telephony as a service (like the postal service!)
Vailism is the philosophy that public services should be run as
closed centralized monopolies for the public good
OAM: Application-driven Evolution Slide 5
6. What’s the difference ?
In the Bell-Watson model the customer pays
once, but is responsible for :
• Installation (wires, wiring)
• Operations (power, fault repair, performance
+
– distortion and noise)
• Infrastructure maintenance
While the Bell company is responsible only for
providing functioning telephones, In the Vail
model the customer pays a monthly fee but the
provider assumes responsibility for everything
including fault repair and performance
maintenance
The telephone company owns the telephone
sets and even the wires in the walls !
OAM: Application-driven Evolution Slide 6
7. Service Level Agreements
• In order to justify recurring payments the provider agrees to a
minimum level of service in an SLA
• SLAs should capture Quality of user Experience (QoE) but this is
often hard to quantify
• So SLAs usually actually detail measurable network parameters that
influence QoE, such as :
Availability (e.g., the famous five nines)
Time to repair (e.g., the famous 50 ms)
Information rate (throughput)
Information latency (delay)
Allowable defect densities (noise/distortion)
• Availability (basic connectivity) always influences QoE
• It is hard to predict the effect of the other parameters on QoE even
when there is only one application (e.g., voice)
• When multiple applications are in use – it may be impossible
OAM: Application-driven Evolution Slide 7
8. Some Applications
• System traffic
– Routing protocols, DNS, DHCP, time delivery, system update, OAM,
tunneling and VPN setup
• Business processes
– Database access, backup and data-center, B2B, ERP
• Communications – interactive
– Voice, video conferencing, Telepresence, instant messaging, remote
desktop, application sharing
• Communications – non-interactive
– Email, broadcast programming, music
– Video : progressive download, live streaming, interactive
• Information gathering
– Http(s), Web 2.0, file transfer
• Recreational
– Gaming, p2p file transfer
• Malicious
– DoS, malware injection, illicit information retrieval
OAM: Application-driven Evolution Slide 8
9. What do applications need ?
• Some applications only require availability
• Some also require minimum available
throughput
• Some require delay less then some end-
end (or Real Time) delay
• Some require packet loss ratio (PLR) less
than some percentage
– And these parameters are not necessarily
independent
For example, TCP throughput drops with 1000 B packets
50 ms RTT
PLR
OAM: Application-driven Evolution Slide 9
10. Some rules of thumb
• Mission Critical (and life critical) applications require high
availability
• If there are any MC applications then system traffic requires high
availability too
• MC applications do not necessarily require strict throughput but
always indirectly require
– A certain minimal average throughput
– Bounded delay
• If the MC application uses TCP then it requires low PLR
• Real-time applications require sufficient throughput
– But not necessarily low PLR (audio and video codecs have PLC)
• Interactive applications require low RT delay
– It may be more scalable for a SP to measure 1-way delays
OAM: Application-driven Evolution Slide 10
11. Monitoring an SLA
• The Service Provider’s justification for payment is the
maintenance of an SLA
• To ensure SLA compliance, the SP must :
– Monitor the SLA parameters
– Take action if parameter is dropping below compliance levels
But how does the SP verify/ensure that the SLA is being met ?
• Monitoring is carried out using Operations, Administration,
Maintenance (OAM)
• The customer too may use OAM to see that the SP is compliant !
Technical note: OAM is a user-plane function but may influence control
and management plane operations, for example:
– OAM may trigger protection switching, but doesn’t switch
– OAM may detect provisioned links, but doesn’t provision them
OAM: Application-driven Evolution Slide 11
12. Operations, Administration,
Maintenance
Traditionally, one distinguishes between 2 OAM functionalities :
1. Fault Monitoring: Required for maintenance of basic connectivity
(availability)
• OAM runs continuously/periodically at required rate
• Detection and reporting of anomalies, defects, and failures
• Used to trigger mechanisms in the
Control plane (e.g. protection switching) and
Management plane (alarms)
1. Performance Monitoring: Required for maintenance of all other
QoE attributes
• OAM run :
Before enabling a service
On-demand or
Per schedule
• Measurement of performance criteria (delay, PDV, etc.)
OAM: Application-driven Evolution Slide 12
13. Early OAM
• Analog channels and 64 kbps digital channels did not have
mechanisms to check signal validity and quality, thus:
– Major faults could go undetected for long periods of time
– Hard to characterize and localize faults when reported
– Minor defects might be unnoticed indefinitely
• As PDH networks evolved, more and more OAM was
added on:
– Monitoring for valid signal
– Loopbacks
– Defect reporting
– Alarm indication/inhibition
• The OAM overhead started to explode in size !
• When SONET/SDH was designed bounded overhead was
reserved for OAM functions
OAM: Application-driven Evolution Slide 13
14. OAM for Packet Switched
Networks
• OAM is more complex for Packet Switched Networks
• In addition to the previous defects :
– Loss of signal
– Bit errors
• We have new defect types:
– Packets may be lost
– Packets may be delayed
– Packets may delivered to the wrong destination
• The first PSN-like network to acquire OAM was ATM
(I.610)
– Although technically ATM is cell-based, not packet-based
OAM: Application-driven Evolution Slide 14
15. What about Ethernet ?
• Carrier Ethernet has replaced ATM as the default layer 2
• Ethernet is by far the most widespread network interface
– Ethernet has some advantages as compared to ATM
– It has network-wide unique addresses
– It has a source address in every packet
• But some aspects make Ethernet OAM more difficult
– Connection-Less (CL)
– Multipoint to multipoint
– Overlapping layering – need OAM for operator, SPs, customer
– Some specific problematic ETH behaviors (flooding, multicast …)
OAM: Application-driven Evolution Slide 15
16. What’s the problem with CL ?
• OAM makes a lot of sense in Connection Oriented
environments
– Connections last a relatively long amount of time
– There is some SLA at the connection level
• For CL networks, the network path is neither known nor
pinned, so it doesn’t really make sense to talk about FM
– What does continuity mean if when a link goes down, the
network automatically reroutes around the failure ?
• The Ethernet CL problem is solved by overlaying CO
functionality :
– Flows, or
– EVCs
OAM: Application-driven Evolution Slide 16
17. Ethernet OAM
For many years there was no OAM for Ethernet (LANs don’t need
OAM), now there are two incompatible ones!
• Link layer OAM – 802.3 clause 57 (EFM OAM, 802.3ah)
– Single link only
– Slow protocol, limited functionality
– Some management functions
• Service OAM – Y.1731, 802.1ag (CFM)
– Any network configuration
– Multilevel OAM functionality
• In some cases one may need to run both, while in others only service OAM
makes sense
• Link layer OAM is only for a single link, which is necessarily CO
• Service OAM is most frequently used for infrastructure networks,
which are also CO
OAM: Application-driven Evolution Slide 17
18. MEPs and MIPs
OAM: Application-driven Evolution Slide 18
19. What about MPLS ?
• The other L2 used today is MPLS
• OAM mechanisms that work well for Ethernet can not be used
as-is for MPLS. This is because :
– MPLS does not use absolute addresses
– MPLS packets do not carry source addresses
– when using LDP MPLS is not pure CO
– LSPs are unidirectional entities
• The IETF has defined LSP ping that provides basic OAM
– Continuity
– Trace route
• The ITU defined Y.1711, but it has not seen widespread use
• The MPLS community is now working on MPLS-TP which is
basically MPLS + strong OAM (FM + PM)
– And functionalities dependent on OAM, such as protection
switching
OAM: Application-driven Evolution Slide 19
20. What about IP ?
• It makes sense to monitor IP (IPv4/IPv6) performance as
well
– IP is the most popular end-to-end protocol
– IP connectivity can be purchased (although perhaps not
widely with SLAs)
• But from the OAM point of view, IP is the hardest of all
– the IP protocol suite does not define anything beneath L3
– IP is always pure Connection-Less
• In certain cases it may make more sense to jump directly
to application flows
OAM: Application-driven Evolution Slide 20
21. IP OAM
• For IP, one usually talks about OAM between end-points
• The IETF defines an all-purpose OAM + control protocol :
– ICMP (Internet Control Message Protocol)
• A protocol for FM :
– BFD (Bidirectional Forwarding Detection)
• And two sophisticated protocols for PM :
– OWAMP (One Way Active Measurement Protocol)
– TWAMP (Two Way Active Measurement Protocol)
OWAMP and TWAMP are the only OAM protocols
with full security features !
OAM: Application-driven Evolution Slide 21
22. Summary
• It is advantageous to run networks as provided services
• Service provider income depends on SLA compliance
• SLA compliance requires OAM – FM and PM
• OAM protocols now exist for all relevant technologies :
– TDM – SDH
– Ethernet
– MPLS
– IP
• Ethernet is leading in OAM functionality, but MPLS-TP is
rapidly catching up
• IP can not have FM tools as robust as Ethernet/MPLS, but
already has more sophisticated PM ones
OAM: Application-driven Evolution Slide 22