Infrastructure

CDN providers are bolstering security features to address growing cyber threats, critical for protecting content delivery. Cloudflare and Akamai are integrating advanced DDoS protection, WAF, and Zero-Trust capabilities. These enhancements ensure availability amid rising attack sophistication. Modern CDNs incorporate WAAP to safeguard web applications and APIs at the edge. SSL/TLS encryption is standard, securing data in transit. These features mitigate risks like data breaches and service disruptions, which can degrade p95 performance. The focus on security responds to increased attack volumes targeting e-commerce and media platforms. Robust CDN security reduces latency impacts from mitigation processes. Multi-CDN setups benefit by diversifying security layers across providers. ...

Cloudflare has deployed defenses against MadeYouReset, a newly disclosed HTTP/2 denial-of-service (DoS) vulnerability identified by Tel Aviv University researchers. This flaw could disrupt CDN services by overwhelming servers, impacting availability for websites and applications. Cloudflare’s swift response strengthens its role as a secure content delivery provider. The vulnerability targets HTTP/2’s stream multiplexing, allowing attackers to exhaust server resources with minimal effort. Cloudflare’s existing DDoS mitigation systems, including its WAF, were updated to detect and block these attacks. No user action is required, as the fix is applied globally across Cloudflare’s network. ...

Energy constraints in data centers are delaying new CDN PoP deployments in regions like North America and Europe. Limited power availability hinders providers’ ability to expand capacity, impacting throughput for growing traffic demands. This affects content delivery scalability. Providers are exploring renewable-powered edge nodes to meet sustainability mandates and overcome energy caps. These nodes reduce reliance on traditional grids, enabling new PoPs without increasing carbon footprints. This is critical for maintaining low latency in high-demand areas. ...

Indian Railways has upgraded its e-ticketing platform with CDN enhancements, achieving a record 31,800 tickets booked per minute on May 22, 2025. This boost improves access for millions of users, reducing latency during peak booking periods. The upgrade underscores CDNs’ role in high-traffic public services. The system leverages CDN caching and AI-driven traffic management to handle surges at PoP locations. Enhanced origin shielding protects against unauthorized access, ensuring stable performance. The 31,800 tickets-per-minute figure reflects a significant capacity increase, critical for user satisfaction. ...

Multi-CDN strategies are gaining momentum as businesses seek to avoid service disruptions seen in past CDN outages. Companies like Amazon and Walmart use multiple providers, such as Akamai, Cloudflare, and Fastly, to ensure redundancy. This approach maintains content availability during provider-specific failures. Multi-CDN setups distribute traffic across several CDNs, reducing reliance on a single PoP or origin. By leveraging BGP routing and real-time failover, these systems minimize downtime. For e-commerce, this translates to consistent user experiences, even under high traffic. ...

Major OTT platforms like Netflix, YouTube, and Disney+ are increasingly building their own CDN infrastructure, reducing dependence on third-party providers. This shift challenges traditional CDNs by shrinking their revenue from large clients. It highlights the need for providers to target midsize publishers. In-sourcing involves deploying proprietary PoP networks and origin servers optimized for streaming. This allows OTTs to control latency and costs, achieving lower p95 delivery times. However, it requires significant capital investment. The trend pushes CDN providers to offer specialized services like managed Multi-CDN orchestration. Midsize businesses benefit from these tailored solutions, which improve availability without in-house infrastructure. ...

CDN Overview is a curated index of content delivery network providers. Browse the A–Z list, filter by name, and jump into detailed profiles for scope, features, and references. Filter providers A(6) B(5) C(13) D(1) E(3) F(1) G(1) H(4) I(5) J K(1) L(4) M(5) N(3) O(2) P(4) Q(1) R(1) S(10) T(6) U(3) V(3) W(2) X Y Z #(1) No providers match your search. ...

Selecting the right status code improves client behavior, caching efficiency, SEO, and observability. Pick the status class flowchart TD A[Request handled successfully] A -->|Yes| S[2xx] A -->|No| Q{Client problem} Q -->|Yes| C[4xx] Q -->|No| E[5xx] 2xx: the server accepted and completed the request. 4xx: the request is invalid or not allowed. 5xx: the server or an upstream failed to process a valid request. Success details: 200 vs 201 vs 202 vs 204 flowchart TD S[2xx] --> K{Created new resource} K -->|Yes| C201[201 Created] K -->|No| P{Processing deferred} P -->|Yes| C202[202 Accepted] P -->|No| B{Response body present} B -->|Yes| C200[200 OK] B -->|No| C204[204 No Content] 201 Created: resource was created; include a Location header. 202 Accepted: accepted for processing; finish later; provide a status endpoint or webhook if possible. 200 OK: success with a representation in the body. 204 No Content: success with no body to return. Conditional responses: 200 vs 304 flowchart TD P[Conditional request] P --> J{Representation changed} J -->|No| N304[304 Not Modified] J -->|Yes| N200[200 OK] 304 Not Modified: client can reuse its cached representation. 200 OK: representation changed or no valid validators. Authentication vs authorization: 401 vs 403 flowchart TD A[Access failed] --> X{Credentials present and valid} X -->|No| U401[401 Unauthorized] X -->|Yes| F403[403 Forbidden] 401 Unauthorized: include WWW-Authenticate with the challenge. 403 Forbidden: user is authenticated but not allowed. Validation vs business rules: 400 vs 422 flowchart TD V[Request invalid] V --> P{Syntax or schema malformed} P -->|Yes| B400[400 Bad Request] P -->|No| B422[422 Unprocessable Content] 400 Bad Request: malformed JSON, wrong types, missing required fields. 422 Unprocessable Content: syntactically valid but fails business rules or domain validation. Redirects See the dedicated guide: Redirects Deep Dive: 301 vs 302 vs 307 vs 308 ...

The 1xx class indicates the server has received the request headers and the client should proceed. Bodies are not returned. Most clients handle these automatically. Table of 1xx Codes Code Name Summary 100 Continue Client may send the request body. 101 Switching Protocols Protocol upgrade agreed (e.g., HTTP → WebSocket). 102 Processing Server has accepted the request, still working (WebDAV). 103 Early Hints Hints for preload before final response (RFC 8297). 100 Continue Used with Expect: 100-continue. Lets large uploads avoid sending a body if the server will reject the request. ...

The 2xx class means the request was successfully received, understood, and accepted. Table of 2xx Codes Code Name Summary 200 OK Standard success. 201 Created New resource created; Location may be set. 202 Accepted Processing deferred; result not yet available. 203 Non-Authoritative Information Metadata altered by a proxy. 204 No Content Success, no body. 205 Reset Content Client should reset the document view. 206 Partial Content Range response. 207 Multi-Status WebDAV multi-result. 208 Already Reported WebDAV deduplication of results. 226 IM Used Instance-manipulations applied. 200 OK General success. Caching: Cacheable by default for GET if headers permit. Pair with validators (ETag, Last-Modified) for efficient 304. ...

The 3xx class indicates the client must take additional action to complete the request. Table of 3xx Codes Code Name Summary 300 Multiple Choices Several representations available. 301 Moved Permanently Permanent redirect. 302 Found Temporary redirect (legacy semantics). 303 See Other Redirect to a different URI; use GET. 304 Not Modified Cached representation is still valid. 305 Use Proxy Deprecated. 306 (Unused) Reserved. 307 Temporary Redirect Temporary; method preserved. 308 Permanent Redirect Permanent; method preserved. 300 Multiple Choices Rarely used on the public web; content negotiation is usually implicit. ...

The 4xx class signals a problem with the client’s request. Use specific codes to help clients recover. Table of 4xx Codes (selected) Code Name Summary 400 Bad Request Malformed syntax or invalid parameters. 401 Unauthorized Requires authentication (send WWW-Authenticate). 403 Forbidden Understood but refused. 404 Not Found Resource does not exist. 405 Method Not Allowed Method not supported; send Allow. 406 Not Acceptable No acceptable representation. 408 Request Timeout Client took too long to send. 409 Conflict State conflict; e.g., versioning. 410 Gone Resource intentionally removed. 412 Precondition Failed ETag/If-* precondition failed. 415 Unsupported Media Type Content type not supported. 418 I’m a teapot Non-standard; avoid in production. 422 Unprocessable Content Semantically invalid data. 425 Too Early Retry-unsafe with early data. 429 Too Many Requests Rate limit exceeded. 431 Request Header Fields Too Large Headers too large. 451 Unavailable For Legal Reasons Blocked due to legal demands. 400 Bad Request Use for malformed JSON, invalid parameters, or schema violations. Include machine-readable error details. ...