At three o'clock in the morning that day, the cell phone of technical support was busted. The number of database connections of the customer's chess platform instantly soared to five thousand, and the server traffic charts directly took off vertically - it was not a player revelry, it was a mixed attack of the black production gangs with fake components of the frantic brushing of score scripts and DDoS. Fifteen minutes later, the entire game hall was stuck as a PPT, and the revenue accumulated over three days was brushed away by two hundred thousand dollars in ten minutes.
Chess industry is so cruel. Players want to play cards without lag, voice synchronization zero delay, while the operation team is to prevent the DDoS traffic of dozens of G per second and simulate the behavior of real players “woolgathering” team. Your server bandwidth and then big, encounter SYN Flood or HTTP slow attack as usual lying flat; your business logic and then rigorous, encounter distributed agent pool brush points is also difficult to recognize at a glance. I've seen too many teams to smash the budget on the server hardware, but with a free CDN, a wave of penetration after the night to find a high defense service provider to put out the fire.
High-defense CDN in this line has long been not “optional accessories”, but the line of life and death. However, many people choose the type of easy to go astray: either only look at the defense bandwidth, that 300G must be better than 100G; either blindly pursue low latency, ignoring the loss of security checks. In real scenarios, the three functions of anti-scrubbing, anti-DDoS and low latency must be closed-loop, and one less is the shortest plank of the barrel.
Let's start with anti-scrubbing. Instead of simply brushing the requests, the board game brushing highly simulates the behavior of real people: registering, logging in, matching games, betting, and even losing a few games on purpose. Traditional WAF can't prevent it at all, because the traffic looks too “normal”. Last year, a platform encountered a wave of attacks, each IP request frequency control in the normal operation of human interval, but three thousand IP at the same time to receive the task reward, ten minutes to roll away millions of gold.
The core of this type of attack lies in identity and behavioral recognition. I found that the simple IP frequency restriction is almost useless - the black proxy pool is dynamic IP, blocking one for ten. Must be done in the CDN edge node features buried: TCP stack fingerprints, TLS handshake features, browser Canvas fingerprints and even mouse trails. For example, use this paragraph to configure the behavioral model deployed on CDN07:
Don't believe vendors who say “fully automated guarding”. Machine learning models require at least two weeks of training to differentiate between bots, and must initially be coupled with manual rules. For example, in a Texas Hold'em poker room, a live player will have fluctuating thinking time and a scattering of bets, while a script will have a fixed millisecond interval between hands and always a fixed multiple of bets. The timing analysis module we deployed on CDN5 specializes in detecting such patterns:
DDoS is the most feared by board games, such as HTTP Flood attacking the game lobby query interface, or UDP Flood penetrating the voice chat service. Relying solely on the hard defense of the server room will mistakenly block real players, while pure cloud cleaning and high latency. Now the reliable program is a hybrid scheduling: local traffic is first undertaken by the CDN edge nodes, small traffic attacks directly on the edge of the rules to discard, large traffic attacks are dispatched to the cleaning center.
For example, 08Host's multi-level cleaning strategy is quite practical: first, do rate limiting and protocol compliance verification in the edge nodes to filter out the 70% junk traffic; the remaining traffic back to the source through the high-defense server room, where there is special hardware to analyze the TCP state machine anomaly. Tested against CC attacks, this scheme is 40ms lower than the pure cloud cleaning delay, because most of the traffic does not have to detour to the cleaning center.
But be careful, some vendors boast of T-rated protection has water. Once tested a certain vendor claiming 2T protection, the actual hit to 800G when the entire routing table collapsed, because any of their cast routes did not do convergence. The real anti-D capability depends on three indicators: the coverage density of the cleaning center nodes, the quality of the BGP bandwidth and the delay in the issuance of rules. For example, CDN07's global cleaning nodes can complete traffic scheduling in 50 seconds, while some vendors take three minutes - enough for the game service to crash several times.
Lastly, let's talk about low latency. This is not just looking at the test data given by CDN vendors. The latency sensitivity of board games is extremely high, Texas Hold'em more than 200ms players can perceive lagging, and landlord games should be guaranteed within 100ms. However, the addition of security checksum is bound to increase the computational delay, the key is how to balance.
I have compared three programs: CDN5 Anycast network is really fast, the average latency of the Asian nodes 87ms, but the execution of security rules sometimes take more than 30ms; 08Host using intelligent scheduling, security checks are only triggered by suspicious traffic, the average latency is controlled within 95ms; CDN07 is the most radical, put part of the security logic into the client SDK, the server side only do the verification, the delay is pressed to 80ms but the client size is 2MB larger. The delay is pressed to 80ms but the client volume is 2MB larger.
The really practical solution is dynamic degradation: normal traffic takes the fast path, and only suspected attacks trigger full checksums. For example, this configuration:
There's another point that many people overlook: optimization of WebSocket long connections. Board games heavily use WS to push status updates, and some CDNs have lousy support for WS, either unstable connections or large latency fluctuations. Test CDN5's WS implementation is the best, multiplexing is done thoroughly, maintaining 100,000 concurrent connections when the memory footprint is 40% lower than the competition.
In summary, the selection of high-defense CDN has to be like an arsenal: anti-scrubbing to be smart enough to identify behavioral patterns, anti-DDoS to layered cleaning does not kill, low latency to take into account the security and experience. Do not believe in the publicity of “one key protection” - no one can eat all the scenes. It is recommended that the first business portrait: if it is mainly a card game, focus on the behavior recognition ability; if it is a betting class, focus on the DDoS protection bandwidth; if it is a casual chess and cards, the latency weight should be the highest.
The last spit sentence: these days even CDN have to “defense teammates”. Some vendors will “share” your business data to peers to do the attack characteristics of the library, the result is that your home was hit when others are immune. In the contract, be sure to add data privacy clauses, cleaning traffic logs are best stored locally - after all, the chess industry, security itself is competitive.
(Attachment of measured data: after a project access to CDN5, the downtime caused by DDoS decreased from 180 minutes to 3 minutes per month, the loss of brushing points decreased by 92%, but the average delay increased by 11ms. later switched to the hybrid solution of 08Host, the delay increased by only 6ms, but the cost was lower by 30% -) -No perfect program, only the most suitable trade-offs.)
