Securing BGP: A Case Study (4)
In part 1 of this series, I looked at the general problem of securing BGP, and ended by asking three questions. In part 2 and part 3, I considered the third question: what can we actually prove in a packet switched network. For this section, I want to return to the first question:
Should we focus on a centralized solution to this problem, or a distributed one?
There are, as you might expect, actually two different problems within this problem:
- Assuming we’re using some sort of encryption to secure the information used in path validation, where do the keys come from? Should each AS build its own private/public key pairs, have anyone they want to validate the keys, and then advertise them? Or should there be some central authority that countersigns keys, such as the Regional Internet Registries (RIRs) so everyone has a single trust root?
- Should the information used to validate paths be distributed or stored in a somewhat centralized database? At the extreme ends of this answer are two possibilities: every eBGP speaker individually maintains a database of path validation information, just like they maintain reachability information; or there are a few servers (like the root DNS servers) Continue reading
