CDNs and IXPs: Working Together Towards Increased QoE
At the CDN World Summit last week, three back-to-back presentations highlighted the return of the internet exchange points (IXPs) to the CDN table, with some compelling propositions for CDNs to work with IXPs in a mutually beneficial way.
Some years ago, when running my own CDN, our relationship with the London INternet eXchange (LINX) was critical to our survival as a small business playing "at-scale" live streaming games against the juggernauts of Akamai and Limelight. Not only was the core M-BGP peering central to our quirky multicast-focused CDN easiest to locate in an IXP with so many major networks also present, but the community and policy support gave us access to other networks who—particularly in 2003/2004—were not too familiar with CDNs and their role in the ecosystem.
Now, nearly a decade later, not only are the IXPs are more than aware of how valuable this type of relationship with CDNs can be, but they are proactively working on building these relationships. and while at many CDN conferences we have seen co-location facility providers actively courting almost any network technology service providers, CDNs included, this year was the first time I have seen coherent presentations that focused on why a CDN locating at an internet exchange is so mutually beneficial.
Hernan Arcidiacono, director of technology at IPLAN and member of fiscal commission of LAC-IX, summed it up concisely in this slide:
With a well-managed CDN presence, the IXP becomes increasingly attractive to ISPs and enterprises choosing which co-location facilities to build its network from.
Similarly, the IXP offers the shortest path to reach the most networks—again significantly aligning with the CDN’s own needs.
But more than that, even with private carrier exchanges, this relationship between network interconnection and CDN location can be powerful. Mark Tinka, director of engineering at Seacom, also spoke about IXPs. Seacom provide the significant submarine fibre trunking that runs down both sides of the African continent. From these trunks, spurs are brought ashore at key locations and terminated with carrier exchange hotels.
Tinka highlighted how attractive it is to have international CDNs at their exchanges; most of Africa’s content consumption is English media, making the CDN’s role key in bringing in international traffic:
But it was a final point made by Ben Hedges, chief marketing officer of LINX and echoed in the other presentations, that particularly caught my attention: IXPs, by nature located in a particular geographic location, had a valuable role to play in aiding the increasingly challenging task of meeting local legal and policy compliance on many aspects. LINX has been a thought leader in this space from its outset. Malcolm Hutty, LINX's head of policy, has been one of the leading thinkers in the European internet, network telecoms, and network policy space for many years, and this is reflected in LINX’s position and support for the multi-stakeholder self-regulating internet.
In increasingly complex, regionalised, and self-regulated multi-stakeholder markets—such as those that a CDN may be entering into as it deploys a worldwide network—having a local partner who has a symbiotic and sympathetic relationships with you and is able to advise you on local content policy and regulatory issues, is proving to be an increasingly valuable resource in a world where copyright, competition, net neutrality, and censorship are often rearing their heads.
I suspect that increased cohesion between CDNs and IXPs can help both publishers and ISPs (and of course thier subscribers) get a better overall Quality of Experience. That is, after all, what we are all working toward in this industry.