Can I configure any CDN spending limits?


Hi keycdn,

Are there any spending limits, or protections against “economy” DDoS attacks?


If someone sets up a botnet that downloads large images all the time from my servers via keycdn, could this result in very high CDN bandwidth costs?

If there are, say, 10 000 computers in the botnet, and each botnet computer downloads an 1 MB image 100 times per hour, then after one month this could mean bandwidth costs of about $ 40 000. This makes me worried.
(10 000 users * 100 downloads/user/hour * 0.001 GB/download * say 0.06 $/GB * 24 hours/day * 31 days/month = 44 640 $ / month)

Is there some way to configure a max-spending-per-month? If I understood correctly how keycdn works (see link to other forum topic below [1]), then I charge an account with money, and when/if it runs out of money, the CDN service will automatically shutdown? This sounds good, to me.

Or, might my usually say $100-per-month keycdn account suddenly get a $ 40 000 bill?

Are there safeguards that prevents each IP address from downloading too much? E.g. a max limit of 100 MB per day and IP. Possibly configurable? Because some websites might serve 100 MB movies, whilst others just serve 50 kb HTML pages + optimized images.

(Getting warning emails about unusually high costs isn’t enough IMO — I want a hard spending limit, because I might not notice warning emails whilst on vacation.)

(I’ve asked 2 other CDN providers already, they don’t have any spending limits.)

[1] Related topic, but the other way around — someone needs to kind of not have any spending limits :- )
Custom Recharge Threshold

Best regards,


If auto-payment is disabled, content delivery will stop at a certain point when you run out of credits. Your account will become inactive. Your account will not be charged anymore (no rising dept).
Even if auto-payment is enabled, it’s unlikely that a very large amount is charged during such a short time, but I understand your concern.

Is there some way to configure a max-spending-per-month?

Not a monthly limit but your current credits will be limit. With the prepaid credits you’re on the safe side an no further invoices will be charged if used up.

1 Like

Status: The requested feature is already available. Check answer above.

closed #4