> ISP DNS can be dumb and confuse CDN geolocation. Or they have a vested interest in keeping customers hitting specific locations which may be suboptimal for t

> ISP DNS can be dumb and confuse CDN geolocation. Or they have a vested interest in keeping customers hitting specific locations which may be suboptimal for the end user. Around here some rather have you stay in their preferred AS as much a possible and stick to DCs in Paris than Frankfurt (to direct peering?), even though FRA is a stone throw away. This conveniently disappears when using ISP-independent DNS (at the cost of sometimes, some regional-specific content not being primed in the CDN, which I think is why sometimes downloads start slow then shoot way up). e.g tested quickly today with mtr: - Home to Akamai PAR1 = 8 hops: 1-5: ISP, 5 hops 6-7: Zayo, 2 hops 8: Akamai intx-par1 best: 22, worst: 80, stdev: 10 - Home to Akamai FRA1 = 4 hops: 1-2: ISP, 2 hops 3: Akamai intx-fra1 best: 27, worst: 51, stdev: 4 Yet my ISP DNS consistently throws me towards PAR1. In practice this results in general jitter and reduced throughput (ranging from two-thirds to one third; e.g Xbox game downloads never go above 200Mb/s on par1 but shoot up to 600Mb/s on fra1).