12-May-19 1. Internet Exchange Point. 1.
What is an Internet exchange point?. 2. An Internet exchange point (IXP) is a physical location through which Internet infrastructure companies such as Internet Service Providers (ISPs) and CDNs connect with each other. These locations exist on the “edge” of different networks, and allow network providers to share transit outside their own network. By having a presence inside of an IXP location, companies are able to shorten their path to the transit coming from other participating networks, thereby reducing latency, improving round-trip time, and potentially reducing costs..
3. How Does Internet Internet is a network of networks, composed of User networks connect networks of service to ISPs providers (ISPs) and users Various networks (large or small) are Small ISPs connect to interconnected with larger ISPs one another to form The Internet.
Autonomous Systems. 4. • A network on Internet is called Autonomous System (AS) which is represented by AS Number (ASN) ASN is unique around the world APNIC is in charge of ASN assignment for APAC region (56 economies) Used together with BGP (Border Gateway Protocol) for interconnections with multiple networks (or multi-homing) Networks having ASNs can be more independent, or portable Together with portable IP addresses Like what APNIC members are enjoying....
Internet transit Model-Internet Gateway. 5. Global I n tern et t All custorner routes Transit Provider / Internet Gatevvay ( p strea ) Routes of Cus torn er the w.•or'd routes only D own s tre a rn.
Ordinary Peering Model. 6. Transit Provider A (Upstream) Routes of A and its customers Routes Of B and Its customers Transit Provider B (Upstream) Downstream Customer Downstream Customer Downstream Customer Downstream Customer.
Peering in General. 7. • AS's are interconnected/peered at Internet exchanges points (IXPs) or privately Interconnection/peering is among ISPs / data centres / content providers / content distribution network (CDN) providers / cloud services providers which have different ASNs using BGP protocol For mutual benefits Local Peering Between 2 ASes Among > 2 ASes • For higher performance, lower latency and lower cost • Usually no settlement between peers and cost is shared • Local-to-local traffic do NOT need to route through overseas • Important to local Internet development • BLPA (Bi-Lateral Peering Agreement) • MLPA (Multi-Lateral Peering Agreement).
Private Peering. 8. • A form of BLPA having dedicated point-to-point connection between 2 ASes • Using cross-connect or local loop or IPL to interconnect Cost is usually shared between 2 peers May have multiple connections between 2 ASes for resiliency Not quite cost-effective • Spare bandwidth cannot be used for other traffic Unless the traffic volume is really high Not very scalable.
What is Internet exchange point (IXP) ?. 9. • An IXP is a shared physical network infrastructure over which various Autonomous Systems can do easy peering with one another One physical connection to IXP can be used for interconnections with multiple networks More cost-effective and scalable, especially with more participants ASes to be served by IXP include Internet Gateways, Internet Service Providers (ISPs), Research & Education (R&E) Networks, Cloud Service Providers, Content Providers and Content Delivery Network (CDN) Providers.
Simple IXP architecture. 10. Border Router of ISP A Border Router of ISP D Border Router of ISP B IXP Switch Border Router of ISP C.
IXP with minimum configurations. 11. Border Router of ISP A Border Router of ISP D Border Router of ISP B IXP Switch x 2 (at same location or different locations) Border Router of ISP C.
Total number of circuits for IXP connections. 12.
Main Benefits of IXP. 13. • One main objective of an IXP is to keep local traffic local Important to local Internet development Helps bypass 3rd-party network infrastructure for easy interconnection and direct traffic exchange • among participating networks Reduced cost — cheaper connectivity, often low fixed cost Enhanced network performance — faster speed, larger capacities Reduced latency — lower delay, switching at less than a millisecond Helps encourage development of more local content and local applications • Helps local data centre business and other businesses Everybody benefits • The gain for each may be different but all will gain In the end, the most important outcome is customer/user experience improves • Often considered as Critical Internet Infrastructure locally, regionally or globally.
Value and attractiveness of IXP. 14. • Proportional to the number of different networks (ASNs) connected and the amount of traffic volume • Snowball effect after reaching critical mass The initial period usually is the hardest O Most will take wait-and-see approach Gradually will have good mix of networks of different types E.g. Eyeballs vs Content Business and Consumer Fixed and Mobile.
Simplest IXP Topology. 15. Border Router of ISP A Border Router of ISP D Border Router of ISP B IXP Switch Border Router of ISP C.
IXPs are layer-2 networks. 16. Switched Ethernet • One physical connection for interconnections with multiple networks Only routers are allowed to connect to the switching fabric directly • IXP participants can do direct Bilateral Peering (BLPA) over the layer 2 infrastructure anytime • With Route Server added to the layer 2 infrastructure, IXP participants can also do Multilateral Peering (MLPA) for easier interconnections among everybody Traffic exchange is direct and not going through the route server o • Those called themselves "lX" but serving layer-3 services are considered as transit providers Note that IXPs, transit providers and data centres are not the same things.
Possible Steps for IXP Developement. 17. • Can be gradual, step by step (some steps can be skipped or be done at the same time) • Layer-2 network is the bare minimal Can use private IP addresses if small amount of participants • Public IP addresses next Legal entity issue o • Site resilience is IMPORTANT while equipment resilience is also included Has to have site resilience sooner or later o • Route server(s) with ASN follows RPKI/ROV consideration O • Other value added services DNS: Root / TLDs / Recursive Shared CDN Caches ransit for Cache Fill o.
IP/ASN resources for an IXP. 18. Considered as Critical Infrastructure under APNIC Policy • Using public IP addresses and ASN is recommended • IPv4: /24 / 48 • ASN: 1 (for route server to facilitate multilateral peering) But IXP may need another network to provide transit • Own servers such as network management & monitoring • DNS anycast servers: Authoritative or Cache/Resolving/Recursive • Shared CDN Caches for Participants (Capacity) • Small network.
IXP site with minimum resilience. 19. Border Router of ISP A Border Router of ISP D Border Router of ISP B IXP Switch x 2 (at sarne location or different locations) Border Router of ISP C.
Adding routes for Multilateral peering. 20. RS Routes Redistribute Routes to All.
21. Validator RS RPKl-to-Router (RTR) Validated cache Tagged/Filtered Routes.
Spine and Leaf Architecture for beyond 2 switches.
Port Security is Important. 23. Minimum protection to the layer-2 broadcast domain Strictly one IPv4 address, one IPv6 address and one MAC address per port (physical or virtual) Most IXPs allow just one MAC address per port (physical or virtual) "Violation Restrict" instead of "Violation Shutdown" A few IXPs allow more MAC address per port but still a small number Must also do Ether-type filtering and broadcast/multicast traffic filtering/rate-limiting.
Vulnerabilities of IXPs. 24. Proxy ARP • Why can't all router vendors have Proxy ARP disabled as default? • Cannot stop it totally because of possible human errors • Can only do regular monitoring by checking the ARP table • EVPN over VxLAN technology may help but it is not a simple technology Unknown Unicast Flooding • May happen when there is asymmetric routing seen from an IXP • Can be mitigated by sending proactive ARP check to all active addresses every hour or so • EVPN over VxLAN technology may help but it is not a simple technology Shared Buffer over Multiple Switch Ports • Can cause trouble to multiple connections when there is big congestion on one port Unknown to innocent participants which do not have any congestion • Just be careful when choosing switch models Also avoid switch models with small buffer.
25. Operation/Business/Governance Models for IXPs.
IXP Models. 26. Commercial vs Non-profit Developed economies vs Developing economies Subsidized vs Self-financed Government-led vs Industry-led • No one single model which can suit all situations Neutrality is very important, but not always achieved •.
Commercial vs Non-Profit. 27. Commercial set-up is free to do anything No need to care about neutrality too much IXP may be a service to help other business Non-profit set-up tends to be more cautious Neutrality is more important, at least to the target participants Tend to be more independent from individual participants Tend to offer fewer services.
Developed Economies. 28. IXPs are business Multiple IXPs But if they cannot keep intra-economy traffic local, someone needs to step up • Even for not-for-profit set-up • Less government involvement • Keen competition • Government? Industry group? Customer pressure?.
IXP and Data Centers in Developed Economies. 29. • They are natural partners Common situation in advanced metro cities Multiple IXPs in one Data Centre A lot of data centres have their IXPs One IXP in multiple Data Centres The same layer-2 broadcast domain Circuit cost is a burden to the IXP A lot of telco's have their IXPs Healthy competition would be good Customers have choices Also for better resilience.
Developing Economies. 30. Some do not have any IXPS yet • Local traffic does not stay local • A lose-lose situation for everybody • IXPs can help Internet development a lot Better to be non-for-profit set-up May need to start with subsidized model May not be a business at all Help from government is mostly needed Active participation of the biggest players is also very important.
Governance for Non-profit IXPs. 31. • Multi-stakeholder bottom-up approach is an approach with good acceptance by the community E.g. membership-based model • Government support is also important At the very least, should get the proper license • Be as inclusive as possible in order to provide maximum benefits to the whole community which it serves • Should be fair and consistent to every participant or member • Should be open and transparent as much as possible.
Membership-Based Model. 32. • Networks connected can join as members Open membership vs closed membership Mandatory membership vs optional membership • Full Members with voting rights vs Associate Members without voting rights Licensed ISPs vs others Local legal entities vs overseas legal entities • Governance by the Board elected Policy decisions Financial responsibilities • Government's role A facilitator at the very least.
Neutral Locations. 33. May choose one of the followings as starting point: • IJniversity Landing Station Technology Park 0 Carrier Neutral Commercial Data Center Government Data Center • Having multiple carrier options with easy access is important • Should maintain neutrality continuously Expansion to multiple sites within the same metro area can be done on Day 1 or • be done gradually coupled with growth This also helps improve neutrality as more options are provided.
Geography. 34. • IXP usually is NOT expanded beyond a metro area so as to avoid competing with IXP participants and to maintain neutrality And simple port charging model can be used • Usually start with the biggest city first and gradually set up separate infrastructure in other bigger cities one by one.
To Add Value. 35. Domain Name Infrastructure: DNS infrastructure is very important to Internet operations so Root/TLD DNS server instance(s) should be connected directly to IXP for direct peering in order to benefit all participants for better DNS performance and resilience Shared CDN Caches: Connecting cache servers of popular content to the IXP will help everyone save bandwidth, but the cost of the transit bandwidth needed for cache-fill has to be properly_ shared by the ISPs benefited Different CDN providers have different supported models Need to think about long-term sustainability NOTE: Transit for the above should NOT be used for providing usual transit ervice to IXP artici ant so as to maintain neutralit.
Financial Model for Non-Profit IXPs. 36. Seed money? • Perhaps from subsidies and/or sponsorship/donation • IXPs need money to operate continuously Need to have a long-term sustainable finance model for full cost recovery of CapEx and OPEX All cost should be covered Should not forget about the limited lifetime of the equipment used so must save money for future major equipment upgrade say once every 5 years By setting up a reserve fund Subsidies, sponsorship or volunteers support may not be stable • Those networks which are benefited should all contribute in a fair way A charging model should be devised to help achieve that A good financial model will help sustain the IXP operations in long term.
Charging Model. 37. • Simple port charging model is the most common model in the industry Monthly Recurrent Charge (MRC) provides stable income 1 OOGE port MRC / IOGE port MRC = 3 to 6 IOGE port MRC / GE port MRC = 1 to 4 Volume discount may be applied to encourage more connections for various purposes With or without Link Aggregation For better resilience and/or more bandwidth buffer (headroom) NRC (Non-Recurrent Charge) charged with no contract or no NRC for a fixed-term contract • Charge by usage for shared CDN cache service Accurate usage accounting by trusted party is crucial.
Which Models Can Sustain ?. 38. Pure Business Model Subsidized Model Model relying on sponsorship and/or volunteers Membership-based Model • IXP alone cannot make big money • IXP may just be a value-added service Little issue if it is with good financial model • Funding may or may not be long-term Little issue if funding is long-term • May be risky as sponsorship or support of volunteers • is not guaranteed unless it is small enough and without growth Most neutral • Proper governance is important • Need to have good financial model for long-term • sustainability.
Politics Involved in Early IXP Development. 39. Usually larger ISPs like IXP less than smaller ISPs Smaller ISPs are target customers of larger ISPs so larger ISPs have fear of losing market share Dominant ISPs having >60% of market share think they are the IXPs Larger ISPs refuse to connect to IXP making the value of IXP lower • But IXPs do help provide a level-playing field for smaller ISPs There are multiple possible mitigation options for that but in any case, larger ISPs need to collaborate E.g. separating access networks from Internet gateway / transit network 0 • If hurting the goal of "Keeping Local Traffic Local", then it is lose-lose to everybody Government involvement may help or may hurt the case • It depends on the relationship between the industry and the government Forcing large ISPs to do peering may not achieve the expected outcomes 0 Having an IXP is NOT a magic wand to solve all the issues but collaborative spirit is e •.
Independent Legal Entity for IXP ?. 40. Not critical but highly desirable Allow for demonstration of independence and/or neutrality Such as jointly owned by members Or a separate company from the mother company 0 Possible use of the legal entity License Agreements with participants / members Bank accounts for collecting incomes and spending APNIC membership Do allow transitional arrangement.
Government Funding for IXPs ?. 41. • More needed during infancy stage of IXP development Government usually can only provide one-off funding support • For long-term, IXPs need to have a long-term sustainable financial model Better be together with bottom-up industry-led governance for IXP Align with bottom-up multi-stakeholder approach.
IXP Serving Licensed ISPs Only ?. 42. • Can be a starting point for non-profit local IXP if so desired • But sooner or later, the IXP should be opened up for all kinds of networks including CDN networks, authoritative DNS servers, large enterprise networks (e.g. government departments, universities, banks and hospitals) and overseas networks so as to further enhance the importance and the status of the IXP Can drive down the pricing of Internet connectivity further • With proper environment, the local IXP may become an regional IXP.
Only Few International Gateway Licenses ?. 43. • International Gateways may just do private peering with full mesh among themselves for keeping local traffic local But this may not help lower the cost of local traffic as local traffic is mixed with international traffic • To improve the situation, a local IXP can be set up just for local traffic To separate local traffic from international traffic Access networks and other networks can all connect to it for exchanging local traffic But access networks should be separated from international gateways under the same groups with different ASNs in order to take full advantage of this set-up.
Possible Scenario for improving Local Peering. 44.
IXP across Multiple Cities/Economies ?. 45. • Affect neutrality? Generally considered as competing with participants which provide services across the same set of locations • Bad for non-profit IXPs targeting all kinds of networks or providers? Those that see competition may not join and then it may affect the goal of "keeping local traffic local" Commercial IXPs can take this business risk especially if this may help their other business.
Shared CDN Caches offered by IXP ?. 46. • More and more local IXPs in developing economies want to provide shared caches for their participants to increase their value Cost recovery and cost sharing / accounting are major issues to them though Can do charging by usage which should be fairer • CDN providers are starting to accept such model They still mostly look at cache efficiency (cache hit ratio) and traffic volume for justifications • It should be good to consider it At smaller developing economies Especially for gathering small ISPs together to meet the requirements of CDN o providers.
IXP development work of APNIC. 47. • APNIC strongly believes IXPs help Internet development After all, IXPs serve and benefit APNIC members o In fact, IXPs need IP addresses and ASNs and so are APNIC members themselves o Do more on helping those developing economies • Especially those which do not have any IXP yet o Or those which their only IXP is not functioning well • Training and Technical Assistance work primarily Not just for IXP operators but also for IXP participants Also help talk to major stakeholders to convince them of the benefits of having a local IXP while maintaining neutrality May need help of Community Trainers and Consultants from time to time o Having been supporting IXP development in Fiji, PNG, Vanuatu, Mongolia, Bhutan, • Myanmar, Pakistan, India and others.
IXPs in INDIA. 48. Internet Exchange Points (IXPs) play a key role in the modern internet. They facilitate the interconnection of the various network by providing a common peering fabric. India is blessed with multiple IXPs ran by a diverse set of organisations. Following are the IXPs operating in India. Name of IXP NIXI DE-CIX Mumbai Extreme IX AMS-IX India IIFON Website http://nixi.in https://www.de-cix.in/ https://extreme-ix.org https://www.ams- ix.net/in http://iifon.org Locations Noida, Mumbai, Chennai, Kolkata, Bangalore, Hyderabad, Ahmedabad and Guwahati Mumbai, Hyderabad Mumbai, Delhi, Hyderabad, Chennai and Kolkata Mumbai Kolkata.
TYPICAL IXP CONNECTIVITY for PEERING. 49. Critical Internet Resources Higher Educational Institutions Government Institutions ISPs Telcos Carriers IXP CDNs Cloud Service Providers.
IXP Description. An Internet exchange point (IXP) enables local networks to efficiently exchange information at a common point within a country rather than needing to exchange local Internet traffic overseas. Therefore an IXP is a component of Internet infrastructure that can increase the affordability and quality of the Internet for local communities..