traffic_router

README

Traffic Router

Traffic Router is a prototype reimplementation of the Apache Traffic Control Traffic Router in Go.

Apache Traffic Control is an Open Source implementation of a Content Delivery Network.

Traffic Router is a component of Traffic Control which routes CDN requests. It is both an authoritative DNS server, and an HTTP server.

See: https://github.com/apache/trafficcontrol https://github.com/apache/trafficcontrol/tree/master/traffic_router

Status

This is still a prototype. It's incomplete, and missing many features of ATC Traffic Router.

Implemented

• DNS Delivery Service request handling
• CRConfig loading of Delivery Services
• Matching request FQDNs to Delivery Services
• Coverage Zone file loading
• Coverage Zone lookup and matching request IPs to their nearest Cache Group.
• Initial HTTP DNS request handling (edge.ds-name.cdn-domain.example)
• DNS handling for second HTTP lookup (edge-name.ds-name.cdn-domain.example)
• SIGHUP hot config reloading
• HTTP server, for HTTP Delivery Services
• HTTPS server (untested), with hot reloading of certificates when DSes change without stopping the server
• CRStates polling (untested)
• CRConfig polling (untested)

To Do

• Add maxmind to geolocation (currently just coverage zone file)
• Add Deep CZF coverage zone file
• Fix initial HTTP DNS request, which returns routers, to geo-locate and return closest, instead of random
• Add returning multiple servers to DNS requests (both DNS and initial-HTTP DSes), based on DS settings
• DNSSEC
• test HTTPS server
• test CRStates polling
• Add HTTP-to-HTTPS redirecting
• Add HTTP Certificate handling, for HTTP Delivery Services
• Client Steering
• Add Capabilities handling
• Add Topologies handling
• Change server selection within CG to Consistent Hash, matching the existing Traffic Router, instead of random
• Add failover, if all servers in CacheGroup are Unavailable, use Fallback CacheGroup

Performance

No real performance testing has been done yet.

Here is a list of potential performance bottlenecks which should be tested and potentially fixed.

• Fix to only geo-lookup after confirming FQDN is valid. Drastically improve performance under attack
• Use Tries for FQDN matches, faster lookups