Bandwidth Management: New Use Cases An AdvOSS Slutin White Paper Authrs: Farhan Zaidi and Fawad Pasha Cntact: {farhan.zaidi, fawadpasha}@advss.cm Whitepaper URL www.advss.cm/resurces/whitepapers/bandwidth management new usecases.pdf Fr mre infrmatin, cntact sales@advoss.cm AdvOSS Whitepaper Page 1
Intrductin: Recent years have seen explsive grwth in the usage and deplyment f cnverged services in telecmmunicatin netwrks. These cnverged services include multi media applicatins such as vice, vide, text messaging, file transfers, chatting, nline gaming t name a few. Mst, if nt all f these applicatins are bandwidth hungry in nature and require availability f sufficient bandwidth t be able t prvide sustained service t the users. Devices have becme smarter and mre sphisticated, and are thus able t execute these high bandwidth applicatins much better than ever befre. Since mst f these applicatins are run inside the nrmal Internet brwsing traffic, the Service Prviders are mstly unaware f the discriminatin inside the pipe. That is why they are knwn as the s called Over The Tp (OTT) applicatins since a Service Prvider sees them as cnsuming mre and mre netwrk resurces; in ur case, the resurce in questin is the bandwidth. Service Prviders and even vendrs have jumped t the OTT bandwagn by ffering their wn OTT applicatins cheaply and quickly available t users via their applicatin stres. As a result f this, bandwidth is becming a smewhat scarce resurce in many bradband access netwrks that perate n shared media e.g. WiMAX, Wi fi, GSM, DSL and thers. Hwever, as bandwidth is increasingly becming a cntended resurce, it als pens up pprtunities fr Service Prviders t ffer premium services with higher Quality f Experience (QE) fr OTT and als fr ther specialized high Quality f Service (QS) applicatins t subscribers wh are willing t pay mre fr such QE. Examples f high QS apps include HD vice and vide streaming etc. As a result we ften see such service fferings fr premium services and higher QE frm Service Prviders wrldwide. Demand n the access side therefre, usually far exceeds the available thrughput n the air interface as the subscriber base grws; a phenmenn that happens many a times n wired interfaces as well. Service Prviders are implementing different ways t manage the bandwidth available t users s as t bring its utilizatin mre in line with the business gals. Bandwidth management has thus becme a key issue that needs t be handled. New generatin AAA platfrms, which are already burdened with prviding several advanced features in the emerging telecmmunicatin infrastructure, als have t play a key rle in bandwidth cntrl and management. This white paper discusses sme f the latest trends and techniques used fr Bandwidth Management in the cntext f AAA servers. Typically these techniques apply t wireless links but are by and large applicable t wired bradband netwrks as well. In this paper we use the term Cmmunicatin Service Prvider (CSP) lsely in the sense that it cvers bth; netwrk peratrs as well as prviders f applicatin and ther services. In the fllwing sectins, we prvide critical business use cases and requirements that arise in bandwidth management and the rle that AAA needs t play in that cntext. AdvOSS Whitepaper Page 2
Bandwidth cntrl based n peridically cnsumed data vlume limits Since bandwidth is a scarce resurce in many netwrks, CSPs may want t cntrl bandwidth f individual subscribers based n hw much vlume f data they cnsume within a given perid f time. This perid f time may be daily, weekly, bi weekly, and mnthly r based n subscriptin s perid (billing cycle). A CSP may want t reduce bandwidth if the subscriber has exceeded the data vlume usage beynd a threshld fr that perid. Example wuld be t reduce the bandwidth by 200Kbits/sec if the data vlume has exceeded beynd 2Gbytes during a 24 hur perid. The bandwidth is returned t the riginal subscribed value when the perid has expired. T handle this use case, the fllwing are the technical requirements fr an advanced AAA Sessin Management and usage tracking The netwrk elements prviding services have t supply the cnsumed data vlume t the AAA server during an n ging user sessin. The AAA server needs t keep track f the cnsumed vlume by adding up the usage vlume numbers supplied t it by the netwrk element and maintain that infrmatin in real time user sessins. Therefre, sessin management with tracking f usage is a fundamental requirement f a mdern AAA Quta management Bandwidth needs t be cmpared t the assigned quta and the time perid f that quta in this mdule. If the bandwidth limit has reached within the given time perid fr the subscriber, the quta manger fires an event fr the rest f the system annuncing the expiry f quta fr the subscriber. On each Interim r authrizatin event, the AAA server queries the plicy manager fr any actin related t a change in bandwidth driven by plicy rules. accunting. If the plicy manager replies with an actin t update subscriber s bandwidth, the AAA carries ut that actin. A sphisticated plicy manager with a rule based engine t specify plicy rules n subscriber related data e.g. subscriptin details, prfiles, bandwidth qutas and ther parameters related t service cntrl, rating/charging etc. is an essential part f tday s advanced AAA platfrms. Capability t update subscriber s bandwidth prfile n the service delivery r enfrcement pint via Change f Authrizatin in RADIUS and ther similar AdvOSS Whitepaper Page 3
techniques in Diameter is als an essential cmpnent f an advanced AAA These are messages that are asynchrnusly generated by the AAA server and sent t the netwrk elements, instructing them t update ne r mre subscriber s sessin parameters. Passing the benefit f additinal bandwidth t all users when available in the netwrk There are always sme hurs f the day fr a CSP when subscriber lad and cnsequently bandwidth cnsumptin is reduced. These are called ff peak hurs. Examples may be at the start and end f the business day when peple are traveling t and back t their hmes, late night hurs when mst peple are sleeping and s n. During these hurs, bandwidth availability level becmes much higher in the netwrk. CSPs are mtivated t ffer this available bandwidth as a benefit t the subscribers wh are actively using the service during these hurs. Bandwidth is added t the subscriber s sessin dynamically during these perids. The bandwidth is returned t the riginal subscribed value when the perid has expired. T handle this use case, the fllwing are the technical requirements fr an advanced AAA Technical Requirements: Passing the benefit f additinal bandwidth t sme users based n their subscriptins when available in the netwrk This use case is similar t the previus ne with the nly difference that the CSP may nt want t ffer the benefit f additinal bandwidth availability t all custmers. Instead, they may want t ffer it t custmers wh subscribe t such a benefit by paying extra in the frm f Add Ons t the basic subscriptins. Therefre, we ften see night unlimited packages r special ff peak rates etc. The bandwidth is dynamically added during higher availability perids t nly thse subscriber sessins wh have bught these Add Ons n tp f their subscriptins. T handle this use case, the fllwing are the technical requirements fr an advanced AAA Subscriptin and Add n management in HSS AdvOSS Whitepaper Page 4
HSS is the main data repsitry fr string subscriber credentials, subscriptin infrmatin and add ns etc. Unlimited plans and Fair Usage Althugh, CSPs usually differentiate services based n available bandwidth, they always want t create rm fr high paying subscribers wh demand unlimited bandwidth and cnsumed data vlumes withut restrictins. Therefre, mst CSPs have an unlimited package r service ffering available fr premium users. Althugh, such packages d nt have upper limits n bandwidth, CSPs usually want t have a plicy in place called Fair Usage. This plicy dictates that the bandwidth f a subscriber n an unlimited plan with n data vlume cap needs t be reduced by an amunt if the data usage reaches a predefined upper threshld within a certain time f the subscriptin perid. Fr example, such a plicy might say that reduce the bandwidth f a subscriber n unlimited plan by 200 Kbits/sec if she reaches an upper value f 20 Giga Bytes in her usage/cnsumptin f data vlume befre half f the mnth (assuming the subscriptin is n a mnthly basis). The plicy rule might say further that the bandwidth shuld be reduced by anther 200Kbits/sec if the subscriber cnsumes 5GBytes vlume in subsequent 5 days and s n. The idea behind such a plicy is t be able t prvide premium service t high paying users while remaining fair t ther lesser paying users s that the unlimited custmers may nt ccupy mst f the bandwidth, thus leaving n rm fr ther users. T handle this use case, the fllwing are the technical requirements fr an advanced AAA Subscriptin management in HSS Sessin management and usage tracking Fair usage is a plicy and may have variants in different CSP envirnments. A sphisticated plicy manager with a rule based engine t specify plicy rules n subscriber related data e.g. subscriptin details, prfiles and ther parameters related t rating/charging etc. is an essential part f tday s advanced AAA platfrms. AdvOSS Whitepaper Page 5
On Demand bandwidths This is a very advanced use case where a CSP may want t give an ptin t the subscribers n their wn self care prtal t increase their bandwidth as and when required fr a given perid f time. Fr example the subscriber self care web page may have a buttn and an assciated time perid with it e.g. ne day r in 6 hurly time slts where the subscriber may chse t increase the bandwidth t a higher level than the riginal subscribed ne. The bandwidth returns t the riginally subscribed ne when the chsen perid is ver. This facility may be available t users wh have bught this as an Add n t the basic subscriptin. T handle this use case, the fllwing are the technical requirements fr an advanced AAA Subscriptin and Add n aware management in HSS r SuM HSS is the main data repsitry fr string subscriber credentials, subscriptin infrmatin and add ns etc. Subscriber self care prtal Applicatin level cntrl and charging In this case, the OTT and ther premium applicatins e.g. HD vice r vide etc. need t be cntrlled individually by CSPs. The individual applicatins are cnsidered as flws which may be pre prvisined with the subscriptins and special premium rates and qutas assciated with them. Fr example, a subscriber may be n a plan that ffers 30% f the ttal subscribed bandwidth reserved fr VOIP traffic, 20% fr HD vice, 10% fr trrents and the rest fr nrmal Internet brwsing. The subscriptin t the plan may als have mnthly upper limits n the cnsumptin f vlumes fr each individual flw. If the subscriber is nt using a flw at any given time, the bandwidth dedicated t that flw is usually made available t her ther flws. The basic requirement fr this kind f use case is the capability f the netwrk element acting as the service delivery pint t be able t discriminate and enfrce qutas n individual flws inside the subscriber s data traffic by deplying Deep Packet Inspectin (DPI) techniques. T handle this use case, the fllwing are the technical requirements fr an advanced AAA AdvOSS Whitepaper Page 6
Capability t push different prfiles t netwrk elements thus enabling them t enfrce the qutas assigned t each flw during Authenticatin r Authrizatin. Subscriptin and Add n management in HSS r SuM that is aware f the different prfiles related t different types f qutas assigned t flws Flw based accunting and charging capability Cngestin awareness and bandwidth cntrl based n that (including thrttling) CSPs may want the netwrk t remain free f cngestin by aviding running int the cngestin state. This usually requires capability t mnitr cngestin in the netwrk and there culd be netwrk elements dedicated t the task that generate real time reprts abut the current usage f the netwrk bandwidth n a glbal level. The CSPs may want t adjust the bandwidth f individual subscribers in active sessins and may als want t blck r restrict new sessins t belw a threshld till the state f cngestin subsided. T realize this use case, the fllwing are the technical requirements fr an advanced AAA Capability t receive real time reprts frm the cngestin mnitring netwrk elements Cngestin cntrl calculatin mdule that wuld generate platfrm events regarding cngestin Plicy manager AdvOSS Whitepaper Page 7
Cnclusins Due t the explsive grwth f data centric services cupled with OTT applicatins, demand fr bandwidth n access netwrks has grwn expnentially in recent years. On ne hand, this unprecedented grwth has created new and interesting revenue pprtunities fr CSPs t ffer differentiated and premium services fr subscribers willing t pay mre fr additinal bandwidth; it has als created significant challenges fr AAA platfrms that sit at the cre f a CSP netwrk. Nw, AAA applicatins need t prvide bandwidth management and cntrl capability in cnjunctin with several ther mdules and applicatins such as Plicy Managers, Subscriber managers, quta mangers, self care captive prtals t name a few. AAA platfrms are therefre quickly turning int cmplete Service Management platfrms and must supprt capability fr extensibility, scalability and prgrammability fr realizing advanced business lgic and use cases. In this whitepaper we have tried t capture sme f the mst imprtant business use cases in the cntext f bandwidth management and the challenges these use cases pse fr a mdern AAA platfrm. AdvOSS Whitepaper Page 8
Abut AdvOSS: AdvOSS is an emerging B/OSS and Switching vendr that ffers cre t edge Billing, AAA & Call Cntrl prducts t diverse range f Cmmunicatin Service Prviders (CSPs) acrss the glbe. It prvides custmizable, scalable and cst effective slutins that add value and reduce verall perating expenses f Telecm Operatrs & CSPs. Mre than 400 medium size custmers and many Tier 1 telecms in 40 cuntries rely n AdvOSS prducts fr their business. This includes leading Operatrs like Wateen Telecm (Warid Telecm Grup), Qatar Telecm, Orascm Telecm and many ther CLECs and Carriers. Fr mre infrmatin, visit ur website www.advoss.cm r cntact us at sales@advoss.cm AdvOSS Whitepaper Page 9