Route Server Description
Route Server Operation and Community Usage
Automatically and continuously according to the following schedule:
- Every 15 minutes — data is retrieved from IRR databases;
- Every 4 hours — each Route Server is updated;
- 2-hour offset between servers — RS0 is updated first, and the same data is pushed to RS1 two hours later.
- RS0: 193.25.180.255/23, 2001:7F8:63::FF/64;
- RS1: 193.25.181.0/23, 2001:7F8:63::FFFF/64
ASN: AS31210
AS-SET for filter generation:
- IPv4: AS-DTEL-IX
- IPv6: AS-DTEL-IX-V6
| Description | Basic RFC 1997 |
Extended RFC 4360 |
Large RFC 8092 |
|---|---|---|---|
| Do not re-announce to any peer (highest priority) | 0:31210 | rt:0:31210 | large:31210:0:31210 |
| Do not re-announce to a peer with a 16-bit ASN | 0:X | rt:0:X | large:31210:0:X |
| Do not re-announce to a peer with a 32-bit ASN | — | rt:0:X | large:31210:0:X |
| Re-announce only to a peer with a 16-bit ASN | 31210:X | rt:31210:X | large:31210:31210:X |
| Re-announce only to a peer with a 32-bit ASN | — | rt:31210:X | large:31210:31210:X |
| Announce to all peers (default, lowest priority) | 31210:31210 | rt:31210:31210 | large:31210:31210:31210 |
| Prepend your own ASN to the AS-path X times towards ASN Y. 1 <= X <= 3 |
— | — | large:31210:6500X:Y |
| Prepend your own ASN to the AS-path X times towards all peers. 1 <= X <= 3 |
— | — | large:31210:6500X:31210 |
| Blackhole for IPv4 /32 or IPv6 /64 prefix | 65535:666 | — | — |
Simple Remote Triggered Firewall
The Simple RTBH mechanism allows a participant to drop all traffic towards a specific host within their network at the DTEL-IX edge.
Only /32 (IPv4) or /56 and more specific (IPv6) routes are accepted.
To activate blackholing, both of the following communities must be set:
- 65535:666 — standard BLACKHOLE community according to RFC 7999
- 31210:X or target:31210:X, where X is the ASN of the peer whose traffic should be dropped
Note: RTBH works only if both communities are applied at the same time: 65535:666 and 31210:31210.
Advanced Remote Triggered Firewall
The Advanced RTBH feature allows not only dropping traffic but also redirecting it to the DTEL-IX Firewall, specifying which type of traffic should be filtered or rate-limited.
It uses the same base community structure as Simple RTBH, with an additional extended community that defines the traffic type:
| Traffic Type | Drop Community | Shape Community |
|---|---|---|
| All UDP traffic | target:31210:1017000000 | target:31210:1117000000 |
| UDP, Src Port 53 (DNS) | target:31210:1017000005 | target:31210:1117000005 |
| UDP, Src Port 123 (NTP) | target:31210:1017000010 | target:31210:1117000010 |
| UDP, Src Port 389 (LDAP) | target:31210:1017000050 | target:31210:1117000050 |
| UDP, Src Port 1900 (SSDP) | target:31210:1017000100 | target:31210:1117000100 |
Drop Community — drops all packets matching the specified rule.
Shape Community — rate-limits matching traffic to 5 Mbps.
Informational Communities
| Route received from a peer with a 16-bit ASN | 31210:X | ro:31210:X | large:31210:31210:X |
| Route received from a peer with a 32-bit ASN | — | ro:31210:X | large:31210:31210:X |
Prefix Geotag (X – continent code, Y – ISO 3166-1 country code)
|
6500X:10YYY | — | — |
- Does not announce default routes, private networks, or private ASNs;
- Shares the full routing table with all connected clients and allows flexible policy control using specific BGP attributes (see details below);
- When receiving routes from a client, the Route Server sets the next-hop to the original router that announced them and redistributes those routes to other participants as-is.
Therefore, only routing information is exchanged via the Route Server, while the actual traffic flows directly between participants.
The most up-to-date description is always available via whois
Detailed information about DTEL-IX members that exchange routing information via the Route Server can be obtained from the RIPE database by querying the description of AS31210 (RS):
whois -h whois.ripe.net as31210
Prefix Filtering Rules
When building inbound prefix filters, the whois.radb.net database is queried, and the Route Server applies filtering to received announcements based on the following principles:
- Announcements of private networks are not accepted;
- Announcements from private ASNs are not accepted;
- Default route announcements are not accepted;
- Announcements from AS XXX are accepted only if the origin value belongs to an allowed AS range;
- Announcements from AS XXX are accepted only if the originating ASes are explicitly listed in the routing policy of AS XXX as being exported to AS31210.
- Prefix-list generation based on connected autonomous systems and IRR filtering;
- Support for both IPv4 and IPv6;
- RPKI support;
- BFD support;
- Blacklist for ASNs and prefixes;
- Prefix-to-geo mapping support;
- Simple Remote Triggered Blackhole (RTBH) for DDoS mitigation;
- Advanced Remote Triggered Blackhole with redirection to the DTEL-IX firewall for more granular DDoS filtering;
- Flowspec support with redirection to the DTEL-IX firewall.
- RFC 1997 – BGP Communities Attribute
- RFC 4360 – BGP Extended Communities
- RFC 4384 – BGP Communities for BGP-Mapping
- RFC 4893 / RFC 6793 – 32-bit ASNs
- RFC 7947 – Internet Exchange Route Servers
- RFC 7999 – BLACKHOLE community
- RFC 8092 – BGP Large Communities
- draft-hilliard-ix-bgp-route-server-operations