OpenBGPD - Adding Diversity to the Route Server Landscape

Performance

In previous versions of OpenBGPD, the filtering performance didn't allow proper filtering of all EBGP sessions. Current best practice at IXP Route Servers is to carefully evaluate and validate of all routes learned from EBGP peers. The OpenBGPD ruleset required to do correct filtering (in many deployment scenarios) was simply too lengthy - and negatively impacted service performance during configuration reloads. While filtering performance is the biggest bottleneck, general improvements to the Routing Information Base were also made to improve scalability. IXP Route Servers with a few hundred peering sessions are commonplace and adding new sessions shouldn’t impact the Route Servers’ service to other peers. We found that performance was the most pressing issue that needed to be tackled.

Lack of RPKI Origin Validation

As we've seen, Internet operators aremoving to adopt RPKI based BGP Origin Validation. While it was theoretically possible to emulate RFC 6811-style Origin Validation in previous versions of OpenBGPD, the required configuration wasn’t optimised for performance and wasn’t user friendly. We believe that BGP Origin Validation should be as easy as possible - this requires BGP-4 vendors to implement native, optimised routines for Origin Validation. Of course, enabling Origin Validation shouldn’t have an impact on performance either when processing BGP updates or when updating the Route Origin Authorisation (ROA) table itself.

Portability

OpenBGPD is an integral part of OpenBSD, but IXPs may prefer to run their services infrastructure on an operating system of their choice. Making sure that there’s a portable OpenBGPD version which follows the OpenBSD project release cycle will give IXPs this option.

Development steps

By addressing the issues mentioned above, we could bring back OpenBGPD as a viable Route Server implementation.

Since I was one of the core OpenBGPD developers, I was asked if I wanted to pick up this project again. Thanks to the funding from the RIPE NCC Project Fund , this was possible. Starting in June 2018, I worked full time on this important community project. Over the last few months, many of the problems are already addressed and are now part of the OpenBSD 6.4 release. So far, 154 commits were made to OpenBGPD during the 6.4 development cycle - around 8% of all commits ever to OpenBGPD! This shows that due to funding and dedicated resources, a lot of work could be pushed into the latest release of OpenBGPD.

OpenBGPD 6.4

The OpenBGPD version, as part of OpenBSD 6.4 release, demonstrates great progress. Even though there have been many changes to the core of OpenBGPD, the released version is as solid and reliable as previous releases and the many bug fixes and improvements make this the best OpenBGPD release so far. The changes in the filter language allow users to write more efficient rulesets while the introduction of RPKI origination validation fixes an important missing feature. For IXPs, OpenBGPD now is an alternative again. There are still open issues, but the gap is closing!

Feature highlights

The following changes should be highlighted: