Introduction to Peering & Internet Exchange Points - LACNIC

cu.ipv6tf.org

Introduction to Peering & Internet Exchange Points - LACNIC

Introduction to Peering &Internet Exchange PointsLACNIC Annual MeetingMonday, May 25, 2009Bill WoodcockResearch DirectorPacket Clearing House


ISP Lifecycle: Simple AggregatorSingle Transit ProviderIXPsISP NetworkCustomers


ISP Lifecycle: Redundancy and LCRRedundant Transit ProvidersIXPsISP NetworkCustomers


ISP Lifecycle: Local PeerRedundant Transit ProvidersIXPsISP NetworkSingle IXPCustomers


ISP Lifecycle: Network Service ProviderRedundant Transit ProvidersIXPsNSP NetworkMultipleIXPsCustomers


Hot Potato RoutingRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingRed Customer sends to Green Customer viaRed NSPRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingRed NSP delivers at nearest IXPRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingGreen NSP backhauls from distant IXPRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingGreen ISP delivers to Green CustomerRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingGreen Customer replies via Green NSPRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingGreen NSP delivers at nearest IXPRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingRed NSP backhauls from distant IXPRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingRed NSP delivers to Red CustomerRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingRed Network is responsible for its own costsRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingGreen Network is responsible for its own costsRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


Hot Potato RoutingSymmetry: Fair sharing of costsRedundant Transit ProvidersRedundant Transit ProvidersRed NSPNetworkIXPGreen NSPNetworkRed CustomerIXPGreen Customer


The efficiency of the Internetdepends upon this principle:For any two parties who wish toexchange traffic, there must be a pairof exchanges, one near each party.


The manifestationof this inefficiency:Countries which havenʼt yet builtInternet Exchange Pointsdisadvantage themselves, and exportcapital to countries that already have.


One More CatchOf multiple possible traffic paths,customers will choose the one with thelargest capacity, not the one with thelowest cost or lowest utilization.


One More CatchCapacityTime


One More CatchTherefore, every ISP must make sure thattheir lowest-cost connection is also theirhighest-capacity connection, even if thatmeans very low initial utilization.Otherwise, an IXP will fail to grow, andwill not produce enough bandwidth tooverturn existing market dynamics.


A Closer Look at The Economicsof Internet Exchange Points


Tools for thinking about InternetExchanges in economic termsWhat are we, as ISPs, selling?The right to modulate bits.That right is a perishable commodity.Where do we get the potentiallymodulatablebits?


The right to modulate bitsAny Internet connection is a serial streamof time-slices.Each time-slice can be modulated with abinary one or zero, one bit.Each customer purchases potentiallymodulatablebits at some rate, forexample, 2mbps, which is 5.27 trillionbits per monthly billing cycle.


Thatʼs a perishable commodityThe quality (as opposed to quantity-per-time) characteristics of anInternet connection are loss, latency, jitter, and out-of-order delivery.Loss increases as a function of the number and reliability of components in the path,and the amount of contention for capacity.Latency increases as a function of distance, and degree of utilization of transmissionbuffers by competing traffic sources.Jitter is the degree of variability in loss and latency, which negatively affects the efficacyand efficiency of the encoding schemes which mitigate their effects. Jitter increasesrelative to the ratio of traffic burstiness to number of sources.Out-of-order delivery is the portion of packets which arrive later than other,subsequently-transmitted packets. It increases as a function of the difference inqueueing delay on parallel paths.All of these properties become worse with time and distance,which is a reasonable definition of a perishable commodity.


So where do we get the bits?The value of the Internet is communication.The value is produced at the point at whichcommunication occurs between two ISPs,and it is transported to the customers whoutilize it.Thus, all the bits we sell come from anInternet exchange, whether nearby, or faraway.


An analogyLetʼs look at another perishablecommodity with more readily observedeconomic properties... Bananas.


Value decreases with time & distanceThe value of a bananadecreases, the further it getsfrom the farm which produced it.The shelf-life which theconsumer can expectdecreases, and eventually itbecomes overripe, then rotten.


Cost increases with time & distanceThe cost of a banana increases,the further it gets from the farmwhich produced it.Salaries and hourly labor,warehouse leasing, diesel fuel,truck amortization, loss andspoilage, insurance, and otherfactors contribute additively.


In a competitive environment, retail price is limitedby competition, so time and distance influence theprice more than the number of middlemen.


The problem is the same:ISPs form a delivery chain, bringing perishablebits to the consumers who purchase them.


So how do we improve things?


Bring the customer nearer an IX...High costLow valueLow costHigh value...or bring an IX nearer the customer.


So how do we recognize asuccessful exchange?The purpose of an IX is to lowerparticipating ISPsʼ average per bitdelivery costs (APBDC).A cheap IX is probably a successful one.An expensive IX is always a failure.Reliability is just hand-waving bysalespeople.


How to Build anInternet Exchange Point


Determining NeedSufficient end-user base?No existing facility to build upon?Sufficient degree of locally-destinedtraffic?


Geographic LocationUser populationFiber facilities or rights-of-wayFounding participants


DensityCentralized in one roomCampus of adjacent buildingsMANFrame / ATM / SMDS / MPLS cloud


Building ManagementTelco hotelUniversity computing ortelecommunications facilityCity emergency services facility


In-Building FacilitiesPathwaysPowerCoolingAccess and security


ServicesSwitch fabricCrossconnectsRoute-serverRemote handsNTPWeb caching


Business StructureIncorporated or unincorporated?Staffed or volunteer?Non-profit or for-profit?Cooperative or external ownership?Cost-recovery (predictive or actuals), adhoc,or market pricing?


PoliciesBLP, MLPA or MMPLA?Mandatory looking-glass?Routing and switch-port informationpublic or members-only?Disclosure in the event of securityproblems, failures, or mistakes?Extensible switch fabric?


Thanks, and Questions?Copies of this presentation can be foundin Keynote, PDF, QuickTime and PowerPoint formats at:http:// www.pch.net / resources / tutorials / ix-constructionBill WoodcockResearch DirectorPacket Clearing Housewoody@pch.net

More magazines by this user
Similar magazines