BGP Large Communities - AS47536

Format: All communities use 47536:TYPE:ASN - Large communities only (RFC 8092)
Note: Standard communities are accepted for RTBH only (65535:666 and 47536:666)
Current network details: See PeeringDB and BGP.tools

Informational Communities

These are automatically added by AS47536 to routes we advertise to you:

Community	Description
`47536:150:0`	Transit routes (general)
`47536:150:ASN`	Transit routes learned from specific transit ASN
`47536:300:0`	Public peering routes (IXP, general)
`47536:300:ASN`	Public peering routes from specific IXP RS ASN
`47536:400:0`	Private peering routes (PNI, general)
`47536:400:ASN`	Private peering routes from specific peer ASN
`47536:500:0`	Customer routes (general)
`47536:500:ASN`	Customer routes from specific customer ASN
`47536:47536:0`	Routes originated by AS47536

Action Communities

Set these communities on your announcements to control how we propagate your routes:

Per-Transit Controls

Supported transit ASNs: 49600 (NEAR IP), 5405 (Inter.link), 34927 (iFog), 6762 (TIS Seabone), 34549 (meerfarbig), 50869 (IPTP)

Community	Action
`47536:800:ASN`	Do not announce to specific transit provider
`47536:801:ASN`	Prepend AS47536 1x to specific transit
`47536:802:ASN`	Prepend AS47536 2x to specific transit
`47536:803:ASN`	Prepend AS47536 3x to specific transit
`47536:805:ASN`	Announce ONLY to specific transit (exclusive)

Per-IXP Controls

Supported IXP route server ASNs: 47498 (FogIXP), 61190 (ANIX), 202409 (LocIX), 31142 (KleyReX), 41441 (Speed-IX)

Community	Action
`47536:810:ASN`	Do not announce to specific IXP (via route server)
`47536:811:ASN`	Prepend AS47536 1x to specific IXP
`47536:812:ASN`	Prepend AS47536 2x to specific IXP
`47536:813:ASN`	Prepend AS47536 3x to specific IXP
`47536:815:ASN`	Announce ONLY to specific IXP (exclusive)

General Controls

Community	Action
`47536:890:0`	Do not announce to ANY transit provider
`47536:891:0`	Do not announce to ANY IXP
`47536:892:0`	Prepend AS47536 1x to ALL IXPs
`47536:893:0`	Prepend AS47536 2x to ALL IXPs
`47536:894:0`	Prepend AS47536 3x to ALL IXPs
`47536:895:0`	Prepend AS47536 1x to ALL transits
`47536:896:0`	Prepend AS47536 2x to ALL transits
`47536:897:0`	Prepend AS47536 3x to ALL transits

Special Communities

Community	Action
`47536:666:0`	RTBH - Trigger blackhole (prefix must be /32 or /128)
`65535:666`	RTBH - Standard community alternative
`47536:666`	RTBH - Standard community alternative
`65535:0`	Graceful Shutdown (RFC 8326)

Important Notes

Community Processing Order:
1. DO_ANNOUNCE_TO (exclusive announce) - highest priority
2. DO_NOT_ANNOUNCE (blacklist specific targets)
3. DO_NOT_ANNOUNCE_ALL (blacklist all of type)
4. PREPEND controls (3x, then 2x, then 1x)
MED (Multi-Exit Discriminator): Configured MED values by PathConnect are always applied, even when using community controls
Prepending: Community-based prepending overrides any configured session prepends
Community Stripping: Customer action communities (47536:8XX:*) are removed before propagation
Private Peering: PNI sessions use IXP-style communities (81X series)

Examples

Common traffic engineering scenarios using community combinations:

Example 1: Primary/Backup Transit Setup

Goal: Use NEAR IP as primary, Inter.link as backup
Communities: 47536:803:5405
Result: Route prepended 3x to Inter.link (AS5405), making NEAR IP (AS49600) preferred

Example 2: Avoid Specific Transit

Goal: Do not use iFog transit
Communities: 47536:800:34927
Result: Route not announced to iFog (AS34927), uses other available transits

Example 3: IXP-Only Routing

Goal: Route only via IXPs, no transit usage
Communities: 47536:890:0
Result: Route announced to all IXP route servers, but not to any transit provider

Example 4: Single Transit Exclusive

Goal: Force all traffic through TIS Seabone only
Communities: 47536:805:6762
Result: Route ONLY announced to TIS Seabone (AS6762), not to any other transit or IXP

Example 5: Complex Multi-Transit Engineering

Goal: Primary: NEAR IP, Secondary: meerfarbig (prepend 2x), Avoid: iFog and IPTP
Communities: 47536:802:34549 47536:800:34927 47536:800:50869
Result:

NEAR IP (AS49600) and Inter.link (AS5405) receive route without prepending (primary)
meerfarbig (AS34549) receives route with 2x prepend (backup)
iFog (AS34927) and IPTP (AS50869) do not receive route
TIS Seabone (AS6762) receives route without prepending

Example 6: RTBH (Remote Triggered Black Hole)

Goal: Black hole traffic to specific /32 under DDoS attack
Communities: 47536:666:0 or 65535:666
Requirements: Prefix must be /32 (IPv4) or /128 (IPv6)
Result: Traffic to prefix is dropped at all upstreams supporting RTBH

AS47536 - PathConnect GmbH
Last updated: December 2024