Peering policy

Route servers & communities

Nell-IX runs transparent route servers on AS11859 with RPKI validation and IRR filtering at every location.

Action communities

Attach these to your announcements to control where the route servers send them.

CommunityActionDescription
11859:0:PEER-ASDo not announcePrevent announcement to a specific peer
11859:1:PEER-ASAnnounce onlyAnnounce to a specific peer only
11859:100:YPrependPrepend Y times (1–3) to all peers
11859:101:PEER-ASPrepend oncePrepend once to a specific peer
11859:102:PEER-ASPrepend twicePrepend twice to a specific peer
11859:103:PEER-ASPrepend 3×Prepend three times to a specific peer
11859:666BlackholeRemotely triggered blackhole (RTBH)
Informational communities

The route servers tag routes so you can see where they came from and how they validated.

CommunityMeaning
11859:1000Learned from a route server client
11859:1100RPKI valid
11859:1101RPKI unknown
11859:1102RPKI invalid (filtered)
Route server policy

RPKI

  • Invalid routes rejected
  • Valid and unknown accepted
  • Status tagged with communities

IRR

  • Prefixes checked against IRR
  • RIPE, RADB, ARIN, APNIC
  • Keep your AS-SET current

Prefixes

  • Bogons and martians filtered
  • Default routes rejected
  • Longer than /24 or /48 filtered

AS path

  • Path preserved (transparent)
  • Maximum 64 hops
  • Private ASNs stripped
Configuration examples

Replace YOUR-ASN, RS-IPv4 and prefixes with your values. Route server addresses are on each location page.

Cisco IOS / IOS-XE

! Configure route server session
router bgp YOUR-ASN
 neighbor RS-IPv4 remote-as 11859
 neighbor RS-IPv4 description Nell-IX Route Server
 !
 address-family ipv4
  neighbor RS-IPv4 activate
  neighbor RS-IPv4 route-map TO-RS out
  neighbor RS-IPv4 prefix-list YOUR-PREFIXES out
  neighbor RS-IPv4 maximum-prefix 100
 exit-address-family
!
! Example: don't announce to AS64496
route-map TO-RS permit 10
 match ip address prefix-list DONT-ANNOUNCE-TO-64496
 set community 11859:0:64496
!
route-map TO-RS permit 20
 match ip address prefix-list YOUR-PREFIXES

Juniper Junos

protocols {
    bgp {
        group RS-IPV4 {
            type external;
            peer-as 11859;
            neighbor RS-IPv4-ADDRESS {
                description "Nell-IX Route Server";
                import RS-IN;
                export RS-OUT;
                family inet {
                    unicast {
                        prefix-limit {
                            maximum 100;
                        }
                    }
                }
            }
        }
    }
}
policy-options {
    policy-statement RS-OUT {
        term dont-announce-to-64496 {
            from {
                route-filter YOUR-PREFIX/24 exact;
            }
            then {
                community add no-export-64496;
                accept;
            }
        }
        term announce-prefixes {
            from {
                protocol static;
                protocol direct;
            }
            then accept;
        }
        term reject-all {
            then reject;
        }
    }
    community no-export-64496 members 11859:0:64496;
}

Arista EOS

router bgp YOUR-ASN
   neighbor RS-IPv4 remote-as 11859
   neighbor RS-IPv4 description Nell-IX Route Server
   neighbor RS-IPv4 maximum-routes 100
   !
   address-family ipv4
      neighbor RS-IPv4 activate
      neighbor RS-IPv4 route-map TO-RS out
!
route-map TO-RS permit 10
   match ip address prefix-list YOUR-PREFIXES
!
ip prefix-list YOUR-PREFIXES
   seq 10 permit YOUR-PREFIX/24

BIRD 2.x

protocol bgp RS_IPV4 {
    description "Nell-IX Route Server IPv4";
    local as YOUR_ASN;
    neighbor RS-IPv4-ADDRESS as 11859;
    ipv4 {
        import filter {
            accept;
        };
        export filter {
            if net ~ YOUR_PREFIXES then {
                # Example: don't announce to AS64496
                if net = YOUR_SPECIFIC_PREFIX then {
                    bgp_large_community.add((11859, 0, 64496));
                }
                accept;
            }
            reject;
        };
    };
}

FRRouting

router bgp YOUR-ASN
 neighbor RS-IPv4 remote-as 11859
 neighbor RS-IPv4 description Nell-IX Route Server
 !
 address-family ipv4 unicast
  neighbor RS-IPv4 activate
  neighbor RS-IPv4 route-map TO-RS out
  neighbor RS-IPv4 prefix-list YOUR-PREFIXES out
  neighbor RS-IPv4 maximum-prefix 100
 exit-address-family
!
route-map TO-RS permit 10
 match ip address prefix-list YOUR-PREFIXES
!
ip prefix-list YOUR-PREFIXES seq 5 permit YOUR-PREFIX/24

Need help?

Our NOC can help with route server configuration and troubleshooting.