BGP Customer communities
Tele2 provides the following communities to allow customers to control their announcement and propagation through Tele2s international IP network.
MED
Tele2 accepts MED from customers to adjust the route preference within AS1257.
Local-preference affecting communities
| Community |
Action |
| 1257:110 |
Set local-preference lower than local-preference of transit |
| 1257:120 |
Set local-preference equal to local-preference of transit |
| 1257:130 |
Set local-preference lower than local-preference of peers |
| 1257:140 |
Set local-preference equal to local-preference of peers |
| 1257:150 |
Set local-preference lower than the normal local-preference of customers |
| 1257:160 |
Set local-preference equal to the normal local-preference of customers |
Remote Triggered Black Hole routing
Routes marked with 1257:666 will be Null0-routed in all core and peering routers within AS1257. Announcements from customers are normally strictly prefix-filtered and that prefix-list might need to be adjusted for RTBH to work correctly. Please contact bgp4-adm@tele2.net for further details.
| Community |
Action |
| 1257:666 |
Discard traffic to destination, see RTBH for more information |
No-Export
Tele2 will accept the well known community No-Export from customers.
| Community |
Action |
| No-Export (0xFFFFFF01) |
Discard traffic to destination, see RTBH for more information |
Route announcement control
Customers of Tele2 are offered the following communities to control their annnouncement over Tele2s non-customer peers.
The basic control community follows this model:
650xy:ASN
Where x is the region, for which the permitted values are:
| Value |
Region |
| 0 |
All regions |
| 1 |
North America |
| 2 |
South America |
| 3 |
Europe |
| 4 |
Middle East |
| 5 |
Asia |
| 6 |
Africa |
While y describes the desired AS path
| Value |
Action |
| 0 |
Suppress announcement |
| 1 |
Normal announcement |
| 2 |
Announce and prepend AS1257 once |
| 3 |
Announce and prepend AS1257 twice |
| 4 |
Announce and prepend AS1257 thrice |
ASN is to which AS number the announcement should be changed. A value of 0 means all ASNs. Do note that not all ASNs are supported. To request support for additional ASNs, please contact bgp4-adm@tele2.net.
Examples:
| Community |
Action |
| 65000:0 |
Do not announce to any peer |
| 65001:0 |
Normal announcement to all peers |
| 65002:3320 |
Prepend AS1257 once on all peers with AS3320 |
| 65030:1299 |
Do not announce to AS1299 in region 3 (Europe) |
Communities can be combined, for example 65000:0 and 65011:19151 is valid and would mean that the route would not be announced to any peers except for AS19151 in region 1 (North America). When multiple communities are combined, the following order of priority is applied:
- Specific ASN in a specific region
- Specific ASN in all regions
- All ASNs in one specific region
- All ASNs in all regions
In addition Tele2 offers a community specially targeted for traffic control. It has the same basic functionality as what is described above for prepending with the difference that marking a route for prepending towards a peer does not imply an implicit announcement. The format of the community is 651xy:ASN where x, y and ASN behave in the same manner as the previous route announcement community. This community is implemented as a 2-stage model, where it is first determined whether a route should be announced or not, typically influenced by the previously described community. If the route is determined to be announced, than the 651xy:ASN will affect if the route is to be prepended or not. In short, prepending with 651xy:ASN does not mean implicit announcement and is thus a good candidate when one wants to only control incoming traffic and not affect to whom the route is announced.
