Telecom. White Paper. Prioritizing Mice Flows in Software Defined Networks for Enhanced Monetization and User Experience

Transcription

1 Telecom White Paper Prioritizig Mice Flows i Software Defied Networks for Ehaced Moetizatio ad User Experiece

2 About the Authors Partha Datta Partha Datta has bee workig with Tata Cosultacy Services (TCS) as Associate Head of Telecom Next Geeratio iitiatives (telco cloud Virtualizatio, Software Defied Networkig, HetNet/SmallCells, Devices ad Chipsets) with a focus o equipmet vedors. With a experiece of 15 years across leadig telecom equipmet vedors across the US ad EMEA, Partha advocates a holistic view of the solutios, from busiess ad techical prespectives, to eable value-added trasformatios leveragig extgeeratio techologies. Rajai Srivastava Rajai Srivastava is a Lead Solutios Egieer i the Techology Busiess Uit at Tata Cosultacy Services (TCS). With a experiece of aroud three years, Srivastava has bee a key cotributor to iitiatives ivolvig the ideatio ad implemetatio of SDN applicatios ad solutio accelerators. She has also cotributed sigificatly to the Ope Source commuity o the topic of SDN Cotroller, specifically OpeDayLight. Yogesh Padey Yogesh Padey is a egieer for the telecom domai at TCS, focussig o SDN ad virtualizatio. With a experiece of over two years, he has bee a avid cotributor to implemetig solutio accelerators i ext geeratio techologies.

3 Abstract Software-defied etworkig (SDN) has emerged as a ew tred for dyamic ad flexible etwork traffic optimizatio ad shapig. SDN helps decouple the cotrol ad data plae, ad provides a programmable iterface to the etwork, reducig complexity ad eablig etwork maagers to holistically maage the etwork from a cetral locatio. As SDN cotiues to evolve, applicatios such as badwidth caledarig, traffic re-egieerig, ad subscriber aware route optimizatio will come ito play to eable effective etwork moetizatio. This paper presets a approach for flow optimizatio that factors i user demad for a better Quality of Experiece (QoE). The SDN Cotroller helps meet this demad by cofigurig the etwork dyamically based o the type of applicatio, user services, ad traffic flow at rutime to achieve high performace. The proposed approach discusses prioritizatio of importat flows leveragig moitorig tools like DPI ad sflow; this will eable Over-the-top (OTT) players ad etwork operators achieve better utilizatio ad moetizatio through more adaptable ad resposive cotrol over etwork traffic. The paper also presets the ext steps i eablig a more effective desig by leveragig the SDN Cotroller Service Fuctio Chaiig (SFC) feature.

4 Cotets 1. The impact of mice flows o quality of experiece ad moetizatio 5 2. Prioritizatio of mice flows 5 3. Techical architecture for SDN applicatio 6 4. Use cases for applicatio-aware SDN applicatio 9 5. Movig forward: Leveragig SFC to meet growig etwork traffic requiremets 11

5 The impact of mice flows o quality of experiece ad moetizatio Network data flows are usually categorized as either elephat (log lived) or mice (short lived) flows based o the applicable thresholds set by operators. Flows that are over the specified threshold are categorized as elephat while those below the threshold are categorized as mice flows. The coexistace of elephat ad mice flows impacts mice flows i terms of latecy sesitivity, delay jitter ad cogestio, affectig the quality of experiece (QoE) delivered. A majority of mice flows are geerated by etwork applicatios (like bakig, surfig, chattig) ad largely gover the QoE of the ed user. Prioritizig applicatios withi mice flows as well as mice flows over elephat flows ca thus help deliver better QoE ad eable effective moetizatio. For example: if a user is performig a importat trasactio like bakig (classified:mice) or placig order o amazo (classified:mice) while cocurretly dowloadig a large media (ISO/Torret) file (classified:elephat), followig this approach ca help the etwork operator deliver higher QoE. Alteratively, cosider a sceario where two users browse web pages o Amazo, watch videos o YouTube, text or video chat through WhatsApp, ad dowload movies o Torret simultaeously. The first three istaces geerate mice flows while the last oe geerates elephat flows i the etwork. The rate of flow of the applicatio traffic across the etwork determies the QoE. I this case, the QoE is likely to be impacted as all the liks share the same etwork badwidth. If the first user has subscribed for better QoE o a perapplicatio basis, the etwork eeds additioal itelligece to esure that the user's applicatios are give priority. Prioritizatio of mice flows Network visibility i terms of applicatio recogitio ad flow characterizatio are critical compoets for prioritizig importat mice flows. Curretly, SDN supports policy implemetatio for layers two to four (L2-4) of the etwork but does ot address the same i higher level layers (level 7 or L7), which is importat to esure a applicatio-specific QoE to the ed user. To eable mice flow prioritizatio, or the prioritizatio of applicatios withi mice flows, the etwork eeds applicatio-level itelligece. There are two approaches to achieve this: Deep Packet Ispectio (DPI): This approach leverages third party or ope source DPI ecosystem alog with flow moitorig to extract meta-data for applicatio level visibility. This helps idetify importat mice flows after factorig i user subscribed services ad reegieer the traffic flow patters through SDN Cotroller (OpeDayLight). DPI also gives operators greater cotrol over etworks that carry traffic for a wide rage of services ad applicatios, ad supports itelliget decisio makig. Packet samplig: This approach leverages ope-source badwidth moitorig tools such as Sflow ad Netflow. These tools also provide L2-L4 Iformatio about the type of packet ad classify them as elephat or mice flows based o threshold alerts. 5

6 Techical architecture for SDN applicatio I order to implemet the discussed approach, it is ecessary to desig viable architecture for the SDN applicatio, as show i Figure 1. For the purpose of explaatio, we assume there are two users, emulated as two virtual machies, coected to the iteret through a hybrid OpeVSwitch (OVS) which is part of the SDN. Network moitorig tools such as sflow ad DPI cotiuously moitor the etwork ad are itegrated (via east-west adaptor iterfaces) to the SDN applicatio deployed o the OpeDaylight SDN Cotroller. DPI Egies DPI Moitor QoE Maager Presetatio Tier App Flow Programmer User Services Maager NOC Operator Data packet moitorig SDN Cotroller Iterface Northboud API Gold User Port 1 Port 2 OpeVSwitch Queue 0 Queue 1 Queue 2 Software Defied Network Silver User Iteret Figure : Techical architecture of the SDN applicatio The fuctioal uits of the SDN applicatio are: 1. DPI egies: This module gathers dyamic ad itelliget etwork iformatio from sflow ad DPI,1 icludig applicatio level details. Network applicatios are uiquely mapped to a applicatio ID, as show i figure 2. DPI provides the metadata correspodig to each applicatio ID. For example, the applicatio ID 126 correspods to packets goig to google.com. [1] DPI refers to a DPI library based o OpeDPI ad curretly maitaied by top. This is a ope-source library. 6

7 Figure 2: Output from DPI 2. DPI moitor: While the DPI egie is beig probed o the etwork odes, the DPI moitor qualifies the abstract output. This helps validate that the iformatio is appropriate ad ca be set to the QoE maager for flow optimizatio. 3. Presetatio tier: The presetatio tier eables the etwork operator to set the policies ad rules correspodig to the users ad applicatios that they wat to prioritize. The data is saved as a JavaScript Object Notatio (JSON) file ad udergoes verificatio while matchig the metadata of icomig packets. 4. User services maager: This module serves as the mediator betwee the User Iterface (UI) ad the QoE maager. It records the cofiguratio set by the etwork operator ad allows the QoE maager to implemet the preferece for a specific user ad applicatio, eablig the prioritizatio of importat applicatios. 5. QoE maager: The QoE maager is a key compoet of the SDN applicatio. With the dyamic creatio of priority queues o a etwork ode, this module matches the data from the DPI egies ad user services maager. It the writes correspodig flows to the cotroller, which eables prioritizatio of importat mice flows. 6. Applicatio flow programmer: Usig a OpeDayLight flow programmer API, this uit writes correspodig flows to the cotroller that eable prioritizatio of importat mice flows. To better uderstad the SDN applicatio, let's cosider a mice sceario o oe virtual machie where the user is surfig the web. The secod user is dowloadig a file o the other virtual machie, geeratig elephat flows. The DPI egie ad sflow get the applicatio metadata dyamically from OVS, depedig o the type of applicatio o the etwork. If the metadata matches all the policies set by the operator, specific rules are writte to the etwork to shape the traffic effectively usig a switch queue mechaism. The logical flow of a typical sceario whe the packets come ito the etwork is described i figure 3. It cosists of the followig steps: 7

8 User Service Category User Applicatio Priority Priority {I, II, III} 1 DPI Moitor Applicatio Traffic {Gold, Silver} 6 5 User cofiguratio completed Traffic type: {Elephat, Mice} sflow/dpi 7 Applicatio type: {Amazo, YouTube, Torret} User Services Maager Record User cofiguratio How to chaelize traffic QoE Maager 2 User cofiguratio Retrieve User applicatio priority Ay Service Category cofigured No Retrieve User cofiguratio Yes Applicatio Priority Ay Silver User PI 14 No PI App Flow programmer 12 App Flow programmer Yes All traffic o default queue (Queue 0) App Flow programmer No Actio 4 Queue 0 Queue 1 Queue 2 Queue 3 Queue 0 Queue 1 Queue 2 Queue 3 Queue 0 Queue 1 Queue 2 Queue 3 Queue 0 Queue 1 Queue 2 Queue 3 Figure 3: SDN applicatio process flow The DPI moitor aalyzes the applicatio traffic ad seds the iformatio to the QoE maager. The QoE maager the checks the metadata from the DPI alog with user cofigured data, as show i the boxes marked 1, 2 ad 8. The user policies are cofigured i the presetatio layer, as show i the boxes marked 5, 6 ad 7. I the presetatio layer, the operator ca cofigure the user service category as gold or silver (based o user subscriptio) alog with the applicatios that the user wats to priortize. The user services maager records this cofiguratio as a JSON file. I case o match is foud, rules are ot writte by the applicatio ad all the traffic goes from the default queue (Queue0) as depicted by the path marked 3. If the QoE maager fids the silver user's data o the etwork, correspodig flows are writte to the uderlyig etwork. All the silver user's elephat traffic the moves from aother queue (Queue3), as idicated by paths marked 9 ad 10. If the QoE maager fids the gold user's data o the etwork, the the correspodig applicatio IDs from the DPI moitor ad user cofiguratio are matched, as depicted by path 11. If a match is foud, correspodig flows are writte to the uderlyig etwork. As a result, each applicatio traffic is segragated ito differet queues. For example, YouTube data for the gold user goes from Queue1 ad the Amazo traffic moves from Queue2. This provides a dedicated cogestio free lik to the ed user's priority etwork applicatio, as represeted by paths 12, 13, 14, ad 15. 8

9 Use cases for etwork moetizatio through applicatio-aware SDN applicatios This approach ca be leveraged by the uderlyig etwork i three ways depedig o the type of user subscriptios ad applicatios accessed. I the sceario described earlier, the users have bee classified as gold ad silver based o their service category. Usig the same categories, the followig use cases outlie how a applicatio-aware SDN applicatio ca deliver differetiated data flows based o user subscriptios: 1. Default users: I this sceario, o applicatio is moitorig the etwork. This meas that all the users are default users of the etwork, all packets move from the default queue, ad every user o the etwork gets the same QoE. As illustrated i figure 4, all the packets move through Queue0 ad the average volume of data o the queue is very high. Figure 4: Default etwork state 2. With silver users: Cofigurig a silver user i the etwork requires the segregatio of all elephat traffic o the silver user's lik to a differet queue. Queue4 becomes active ad all elephat flows move to this queue, as show i figure 5. The average umber of packets o the default queue (Queue0) go dow makig it free from large flows ad thereby deliverig better QoE for silver user. 9

10 Figure 5: Network with cofiguratio of silver user 3. With a gold user: Network operators ca specify certai etwork applicatios that eed better QoE irrespective of cogestio i the uderlyig etwork. Cosider a sceario where the gold user is browsig Amazo ad watchig YouTube videos. Out of all the etwork applicatios, the traffic geerated by these classified applicatios move from the default queue to the dedicated queues. As illustrated i figure 6, Queue1 becomes active for the user's Amazo traffic ad Queue2 for the YouTube traffic. This esures that the gold user's applicatios receive dedicated badwidth, providig better applicatio level QoE. The average volume of data o the default Queue0 also reduces, esurig more badwidth for other applicatios. 10

11 Figure 6: With a gold ad silver user I summary, wheever packets are routed through a etwork they are sampled for size ad applicatio meta-data, which is the forwarded to the SDN applicatio. The applicatio checks if the etwork operator has specified policies regardig the packets. The SDN applicatio the writes the rules to the etwork to segregate that particular traffic ad esure better Quality of Service (QoS) through better utilizatio of the uderlyig etwork resources. Movig forward: Leveragig SFC to meet growig etwork traffic requiremets Though the described approach works well o small to mid rage etworks, for scalig to larger etworks there is icreasig iterest i evaluatig the use of service fuctio chaiig (SFC) features i OpeDayLight, as show i figure 7. Usig this feature, the SFC classifier receives the policies from the presetatio tier of the SDN applicatio. The SFC classifier the writes flows that seds all packets from the uderlyig etwork to a DPI-based service fuctio i a overlay etwork. Usig the iformatio from the packets i the overlay, the SDN applicatio writes traffic rules to the etworkig elemets. 11

12 Figure 7: Service fuctio chaiig usig OpeDayLight Usig this approach, the uderlay etwork remais the same while the overlay etwork becomes resposible for traffic steerig or shapig. Coupled with SFC, DPI becomes a shared fuctio across differet etworks that ca be automatically scaled depedig o the users ad etwork traffic. There are differet ways to steer traffic with SFC. The switch queue mechaism for the etwork or Differetiated Services Code Poit (DSCP) markig o each packet help provide better QoS across the etwork fabric. Respodig to growig user demad with SDN A applicatio-aware SDN applicatio eablig prioritizatio of L2-L7 traffic is the ext step forward to eable etwork moetizatio. This paper has highlighted oe possible use case that service providers ad Over-The-Top (OTT) players ca leverage to exted differetiated services o a software-defied etwork. I additio, they ca fulfill such requests without makig chages to the exisitig ifrastructure. Implemetig a agile SDN ecosystem helps OTT players ad etwork operators respod to growig user demads ad maage etwork traffic cogestio efficietly, thereby ehacig user experiece ad satisfactio, a importat differetiator i today's competitive eviromet. 13

13 About TCS' Telecom Busiess Uit For over three decades, TCS has worked with compaies i the Commuicatios idustry, helpig them develop world class solutios ad systems, simplify operatios, augmet etwork services, diversify ito ew markets, ad stay ahead of the competitio. Our solutios address the etire ladscape of telecom busiesses, ragig from greefield start-ups to large cable ad satellite compaies ad equipmet vedors. Our partership model leverages ready-to-deploy platform solutios, proprietary frameworks, ad solutio accelerators to eable our cliets to lauch ew products ad services quickly. TCS' ivestmets i ext geeratio platforms, mobility solutios, capabilities, ad lab ifrastructure are aliged to address our cliets' key busiess imperatives of operatioal excellece, customer experiece, ad reveue ehacemet. We have helped eterprises ulock busiess value i the areas of Digital Chael ad Commerce, Customer Isights, Mobility Solutios, Hosted OSS/BSS (HOBS), IOT & M2M Platforms, Coected Device Maagemet, B2B Platform Ecosystem ad Services ad Network Abstractio layers. Cotact For more iformatio about TCS Telecom Busiess Uit, visit: global.telecom@tcs.com Subscribe to TCS White Papers TCS.com RSS: Feedburer: About Tata Cosultacy Services (TCS) Tata Cosultacy Services is a IT services, cosultig ad busiess solutios orgaizatio that delivers real results to global busiess, esurig a level of certaity o other firm ca match. TCS offers a cosultig-led, itegrated portfolio of IT ad IT-eabled ifrastructure, egieerig ad TM assurace services. This is delivered through its uique Global Network Delivery Model, recogized as the bechmark of excellece i software developmet. A part of the Tata Group, Idia s largest idustrial coglomerate, TCS has a global footprit ad is listed o the Natioal Stock Exchage ad Bombay Stock Exchage i Idia. For more iformatio, visit us at IT Services Busiess Solutios Cosultig All cotet / iformatio preset here is the exclusive property of Tata Cosultacy Services Limited (TCS). The cotet / iformatio cotaied here is correct at the time of publishig. No material from here may be copied, modified, reproduced, republished, uploaded, trasmitted, posted or distributed i ay form without prior writte permissio from TCS. Uauthorized use of the cotet / iformatio appearig here may violate copyright, trademark ad other applicable laws, ad could result i crimial or civil pealties. Copyright 2015 Tata Cosultacy Services Limited TCS Desig Services I M I 06 I 15