Last night at 2:00 a.m., a message suddenly blew up in the technical group, “The official website is hanging, and the traffic is soaring to 200Gbps!”
I poured a mouth of espresso remotely connected up to take a look, good guy, typical TCP torrent attacks mixed with crawlers crazy brush product details page. These days, if you are engaged in e-commerce, you are not embarrassed to say that you are in this business if you have not been subjected to DDoS and reptiles.
E-commerce site is a digital age of the battlefield, on the surface is to sell goods, secretly all the technical attack and defense. You say you server bandwidth to last 100M, attack traffic minutes to you stuffed to 200G. you say you commodity price real-time update? Crawlers half an hour to your bottom price pickpocket bottom pants are not left.
High-defense CDN is no longer an “optional accessory”, but the bottom line configuration of e-commerce survival. But there are so many service providers on the market, in the end how to choose? I have tested CDN5, CDN07, 08Host three mainstream service providers, today to say some big truth.
First of all, the anti-DDoS thing. Do not believe those who claim “unlimited protection” vendors, really encountered a huge flow of cool or cool. Last year, an e-commerce promotion during the use of a cheap CDN, the results were 200Gbps SYN Flood direct penetration, the page was stuck for a whole half hour, heavy losses.
Really reliable high defense CDN must have three layers of cleaning ability: edge nodes preliminary filtering → regional center depth cleaning → cloud black hole diversion. I found that CDN5 Anycast network is really fierce, last year to help a mother and baby e-commerce business to carry a 437Gbps mixed attack, during the period of business without perception.
Configuration should pay special attention to TCP stack optimization. Many CDN default configuration simply can not carry a large number of connections, you have to manually adjust the kernel parameters:
Besides, anti-crawler this hard-hit area. Last week, a digital customer told me that competitors crawl every 5 minutes the whole site price, price adjustment strategy is completely figured out. Ordinary WAF simply can not prevent, you have to use behavior analysis + JS challenge two-pronged.
08Host's smart crawler management is the most thievish I've ever seen - it returns fake data for suspected crawler requests:
The crawler picks off $999, and the real user sees $1199. waiting for the opponent to finish adjusting the strategy according to the fake price, a direct wave of counterattack.
Mobile API protection is even more deadly. Many APPs hard-code API keys on the client side, and crawlers directly simulate APP requests, which can't be prevented. This time you have to use a dynamic token + request signature:
Finally, when it comes to acceleration performance, this is the hidden test point of high-defense CDN. Some vendors sacrifice speed for security, encrypted links to get too complex, TTFB (time to first byte) run to 300ms +, the user ran out early.
The actual test data is very telling: the same from Beijing to Los Angeles, CDN07's BGP line is 47% faster than the ordinary line:
Picture optimization is more the lifeblood of e-commerce.WebP adaptive + intelligent sharpening can improve 20% conversion rate, but many CDN image processing function is weak to poor.08Host's real-time processing engine to support the AVIF format, than the JPEG small 50% is also more clear, which is the real work.
Caching strategy setting is a technical job. I've seen a webmaster cache dynamic pages for 1 hour, and the result is that users see yesterday's prices. You have to refine the management by directory:
Now talk about the selection of pitfalls. Some vendors of the “unlimited protection” in fact hidden mystery: more than the rated traffic directly null route, even cleaning opportunities are not given. Before signing the contract, be sure to confirm three points: the cleaning trigger threshold, the maximum protection capacity, the excess handling strategy.
The price is even deeper. Bandwidth-based billing looks cheap, but immediately goes bankrupt when attacked by traffic. According to the 95 peak billing is relatively reliable, but it is best to set a monthly ceiling price. A cross-border e-commerce business CDN5 guaranteed + elastic program, a month DDoS hit 23 times, the cost did not exceed the budget.
Lastly, I'd like to give a theory: the high-defense CDNs without intelligent scheduling are all half-crippled. Attack traffic only know hard to carry, do not know the normal user scheduling to the unaffected nodes. CDN07 intelligent DNS system can be automatically adjusted according to the type of attack scheduling strategy, SYN attacks go Anycast, CC attacks go distributed cleaning, which is really smart.
Don't leave it alone after deployment. Check the protection reports weekly, I used to use scripts to automatically analyze access patterns:
Let's be honest, doing e-commerce tech these days is like fighting a war. Attack methods are evolving every month, and the protection strategies that worked last year may not work this year. Maintain the frequency of technology iteration, regularly do stress tests, do not wait for the real hit hanging again cry.
In the end, high defense CDN is just a tool, the key is to see how to use. I've seen millions of dollars to buy top CDN results because of the configuration error by the crawler grips bald, also seen the open source program to build their own but to carry 500G attack. The cooperation of people and tools is the ultimate protection.
(Some technical details are omitted at the request of customers, please adjust the specific configuration according to the business scenario)
