What is MANRS?

MANRS (Mutually Agreed Norms for Routing Security) is an industry initiative defining baseline actions networks take to make routing more secure.

It started in 2014 among network operators and has since added programmes for Internet Exchanges, content and cloud providers, and equipment vendors. Participants sign up to a short list of concrete actions rather than a technical standard. For network operators the actions are:

• Filtering: prevent incorrect routing information from spreading, by filtering your own announcements and your customers' against what they are entitled to announce.
• Anti-spoofing: block packets with forged source addresses from leaving your network (source address validation, as described in BCP 38).
• Coordination: keep contact information up to date so other operators can reach you during an incident, for example in PeeringDB and the registries.
• Global validation: publish your routing data so others can check it, with route objects in an IRR and ROAs in the RPKI.

None of this is new technology. MANRS is useful because it turns well-known good practice into a checklist that operators can point to, and a public observatory measures how participants' routing behaves. Joining doesn't make a network immune to incidents, and the many networks that haven't joined still affect everyone's routing, so treat it as a minimum, not a guarantee. For an engineer, the practical value is the checklist itself: if your edge has prefix filters, uRPF or source filters, an accurate as-set, route objects and ROAs, you are doing what it asks. The IRR, RPSL and AS-SETs and RPKI and Route Origin Validation lessons cover the validation side in depth.