1 / 20

A Simulation Approach for Internet QoS Market Analysis

A Simulation Approach for Internet QoS Market Analysis. Bruno Pereira Miguel Martins. Quality of Service. What is the problem?. Internet is plagued by sporadic poor performance. This is getting worse, not better!. Methods are needed to differentiate traffic and provide “services”.

matana
Download Presentation

A Simulation Approach for Internet QoS Market Analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A Simulation Approach for Internet QoS Market Analysis Bruno Pereira Miguel Martins

  2. Quality of Service What is the problem? • Internet is plagued by sporadic poor performance This is getting worse, not better! • Methods are needed to differentiate traffic and provide “services”

  3. What is the problem? • “Poor performance” of the internet service • routing instability • high pack loss in critical NAPs/Exchange Points • server congestion • high variation of transaction times

  4. What is the problem? • Applications are more demanding • end systems are getting faster • end systems use faster network connections • end systems applications wish to negociate performance from the network

  5. Quality of Service: Parameters • Throughput (bytes/s) Which minimum/maximum/average data rate is necessary? • Transmission delay (ms) Which maximum delay is torelable? • Jitter (ms) Which flutuations in the transmission delay are tolerable? • Availability (%) With which probability the communication service is available?

  6. Problem Today Quality of Service Many application will have to address certain Quality of Service (QoS) to achieve the results expected by the user

  7. It would be good if... The network could... • When the user wished to access a priority service: • the network could honor the request • The application could forecast its network load requirements so that: • the network could commit to meet them • When there isn't sufficient bandwidth on one network path to meet the application´s reuirements: • the network could find another path

  8. What is the expectation? • Preferential treatment is an attractive service which customers are indicating the desire to purchase  The Customer is charged at a rate comparable to service level expectations. • Premium differentiated services within the network that will provide predictable and consistent service response for selected customers and traffic flows by: • provision of guarantees on bandwidth and delay • provision of absolute service level agreements • provision of average service level agreements But can the Internet deliver this?

  9. What can not be expected? • QoS is not a tool to compensate for inadequacies elsewhere in the network. • It will not fix: • Massive over-subscription • Complex congestion problems • Sloppy network design No Magic Here...

  10. End-to-EndQoS Service Levels Best Effort Service – Also Know as lack of QoS, best effort service is basic connectivity with no guarantees Differentiated Service, Diffserv (also Called Soft QoS)– Some traffic is treated better than the rest ( faster handling, more bandwidth on average, lower loss rate on average). This is a estatistical preference, not a hard and fast guarantee Guaranteed Service or Integrated Service, IntServ (also Called Hard QoS) – an absolute reservation of network resources for specific traffic

  11. Improving QoS Inside the Internet Simple model for sharing and congestion studies:

  12. Principles for QOS Guarantees • Example: 1MbpsI P phone, FTP share 1.5 Mbps link: • bursts of FTP can congest router, cause audio loss • want to give priority to audio over FTP Principle 1: packet marking/classifying needed for router to distinguish between different classes; and new router policy to treat packets accordingly.

  13. Principles for QOS Guarantees (cont) • what if applications misbehave (audio sends higher than declared rate): • policing: force source adherence to bandwidth allocations • marking and policing at network edge: • similar to ATM UNI (User Network Interface) Principle 2:provide protection (isolation) for one class from others: shaping and policing;

  14. Principles for QOS Guarantees (cont) • Allocating fixed (non-sharable) bandwidth to flow: inefficient use of bandwidth if flows doesn’t use its allocation Principle 3:While providing isolation, it is desirable to useresources as efficiently as possible: scheduling

  15. Principles for QOS Guarantees (cont) • Basic fact of life: can not support traffic demands beyond link capacity Principle 4:Call Admission: flow declares its needs, network may block call (e.g., busy signal) if it cannot meet needs

  16. QoS Market Analysis • Internet QoS Game Model • IAPs (Internet access providers) are competitors (for market share) and cooperators (for global connectivity). • Duopolies often exist in such markets. One IAPs decision has a influence on other IAPs decisions. Thus, they have a strong dependence on each beyond just competitive factors. (Cournot duopoly theory) These characteristics make the internet provision industry suitable for game theoretic analysis, where each player in the game model is a competitor in a market and there are interaction according to their strategic variables.

  17. QoS Market Analysis in rural area • Simulation approach • The paper study the equilibrium outcomes when two IAPs (Internet access providers) interact in rural area. • It´s assumed that there are two firms in the markets and each firm produces identical product and the market quantity of two firms determines the market price. • Each IAP has three factors it can control: • Flate rate pricing or two part tariff • Investment level (network capacity) at 1000, 2000 or 3000 users • BE and QoS services Despite the invesment level, IAP1 assumed to choose unlimited access flat rate QoS pricing and IAP2 is assumed to choose two-part tariff for its QoS pricing.

  18. Simulation approach... • The purpose for each IAPs is to determine the product mix (BE vs QoS) depending on their capacity level and pricing scheme for optimal profits. Hourly QoS rate “r” and QoS connection hours • A range of rate r is from $0 to $3 per hour. • The higher of rate r, the lower the QoS usage percentage. • For example, it r=$0, all users use 100% QoS connection. If r=$3, no one uses QoS connection.

  19. Equilibrium profits... IAP2 IAP1 f1* equilibrium profit function QoS IAP1 with flat rate pricing f2* equilibrium profit function QoS IAP2 with two part tariff • According to the above table, when the network capacities (Ks*) of both IAPs are the same, the IAP2 (with the two part tariff) has a higher profit than the IAP1 (with flat-rate pricing) • When the network capacities are diferent (2K;1K), the IAP with 2K has a higher profit than the IAP with 1K. *1K=1000; 2K=2000 and 3K=3000 users

  20. Conclusions • The results indicate that the IAP with two-part tariff pricing will be better for QoS market. • The two-part tariff allows the IAP to price discriminate among BE (fixed) and QoS uses (variable cost) on a application-by-application basis. • In contrast the flat rate IAP offers less flexibility in this regard, even if they offer both BE and QoS service, since users must choose one or the other.

More Related