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Comment by geofft | Hacker News Reader

I'd say that the historic Akamai model (from the last bubble) counts as "a normal CDN", and in that case, you do change your DNS to point straight at Akamai's DNS servers. For well over a decade now, `www.microsoft.com` has been a CNAME for something run by Akamai.

My rough and uninformed impression is that for small-time users, where "small-time" includes the scale of Reddit, CloudFlare can do what Akamai does at a much more reasonable price.

But yes, that's a different sense of "CDN" from e.g. Google-hosted jQuery.

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> CloudFlare can do what Akamai does at a much more reasonable price.

Not really. Akamai has presence inside many "too big to peer" networks, while CloudFlare doesn't (for now).

You can't just compare CloudFlare to Akamai at the moment, they are following very different strategies.

I assume its for this reason (and others) that even Amazon.com still uses Akamai. Stuff like product images/banners still get served from domains like g-ecx.images-amazon.com (which resolve to Akamai)

CloudFlare seems to be rapidly expanding both datacenters and peering partnerships. Isnt the effective capability the same between both companies?

Is there something that Akamai can do that CloudFlare cant?

There is something which Akamai does and CloudFlare doesn't want to (at the moment): pay big sums to those big ISPs which refuse to peer and want to sell very expensive direct connections.

What does this mean for the company/application using CloudFlare or Akamai?

Both services seem to be highly available and very fast from around the world. What does Akamai do here that's better?

Akamai has direct connections to those "difficult" ISPs, CloudFlare uses transit to reach them.

To provide an example: transit to DTAG via GTT (CloudFlare) is always saturated at peak hours. So Akamai has a big advantage (direct connection) if you want to reach Deutsche Telekom customers.

Oh really, I didn't know Akamai worked like that.

Do you know of any docs describing the algorithm Akamai or CloudFlare use to decide whether to hit your origin server? I'm a stickler for correctness but it seems to be pretty easy to get into the situation where your users aren't getting what you intended. HTTP cache headers are a mess.

To me it seems safer to code your application so the HTML points to JS/CSS/PNG with content hashes in the URL. Then you don't have any cache expiry issues -- nothing ever expires, but you control the assets exactly through your dynamic HTML.

I think it's important to have fast and reliable rollbacks. You can imagine some situation where private content or offensive text is accidentally included with some static asset... I would like some guarantee about when users stop seeing it (preferably as soon as the application is redeployed).

It looks like they determine whether or not the content is static by the extension: https://support.cloudflare.com/hc/en-us/articles/200172516-W... "CloudFlare does not cache by MIME type at this time."

And most likely default to not caching if they are unable to determine.

For dynamic pages you can tell them which ones can be safely cached with PageRules (on paid plans): https://support.cloudflare.com/hc/en-us/articles/200172826-C...

Akamai has an API that you can hit to request that they purge some content of yours from their cache:

https://api.ccu.akamai.com/ccu/v2/docs/

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