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Comment: fixed typo in the BGP-LC community section

titleBi-lateral peering is considered best practice !

While the BGP Route Server service is made available as a convenience, it is strongly recommended that, in addition to any sessions you plan to establish with the BGP Route Servers, you still maintain direct bi-lateral peering sessions with peers that you feel are important to your network! BGP Route Servers should be used to pickup quick/easy/additional peers only, and not as a replacement for your discrete peering policy!

In particular there are many peers that advertise only a subset of their prefixes to the BGP Route Server. Always aim for a bilateral session !

There are two BGP separate route servers on each peering LAN.  It is recommended to always peer with both BGP Route Servers at a location, as sessions to both servers ensure that there is no disruption to your routing should it be necessary to performance maintenance.  The Route Servers do not peer with each other, so peering with only one server is an unnecessary risk.


titleBGP next-as

Ensure that if you do plan on peering with the BGP Route Servers, you understand that the BGP-RS does not attach its ASN to outbound BGP messages.

Please implement the IOS "no bgp enforce-next-as" (or IOS-XR "enforce-first-as disable"), or appropriate equivalent, for your platform.


We recommend that you set the BGP max-prefix to the BGP-RS to 100,000 prefixes for IPv4 and 50,000 prefixes for IPv6

Filtering policy and process

INX has always believed in filtering and we filter all client sessions to the BGP-RS service.  We encourage peers to keep their IRR objects accurate to help us to autogenerate these filters.  

  • Filters are built based on IRRDB registered objects.  
  • Filter generation happens automatically at 04h00 SAST daily.
  • We search the AfriNIC, RADB and RIPE registries (in that order).  
  • We permit more specific (longer match) paths for IPv4, but not for IPv6.   (Note:  we will soon perform only exact match filtering!)
  • Some prefixes are automatically filtered by the route servers (eg. bogons and martians).  
  • We do not accept BGP announcements from private ASNs

BGP Communities for policy control

A simple set of BGP communities are made available for rudimentary policy control.  These will be expanded on, as the BGP Route Server service is enhanced. 

titleRemember to use the correct ASN
Note: The communities example below applies to peers using the JINX route servers. The appropriate ASN for each INX, should be substituted when using the BGP route servers, at other INXes.


0:peer-asndeny to peer-asnblock announcement of prefix to peer-as
0:37700block allblock announcement of prefix to all peers
37700:peer-asnallow to peer-asnannounce prefix to specific peer-as (in conjunction with block all)
37700:37700allow allannounce prefix to all peers (implicit default)

We honour the well-known no-export and no-advertise communities as if they were sent to us as a regular peer.  If you would specifically like us to propagate these, then please tag as below: 

37700:65281add no-exportadds the well known no-export community to all routes sent to peers
37700:65282add no-advertiseadds the well known no-advertise community to all routes sent to peers

BGP Large Community Support for policy control

37700:0:peer-asndeny to peer-asnblock announcement of prefix to peer-asn
37700:10:0block allannounce block announcement of prefix to specific peer-as (in conjunction with block all)all peers
37700:01:peer-asnallow to peer-asblock announcement of announce prefix to all peersspecific peer-as (in conjunction with block all)
37700:1:0allow allannounce prefix to all peers (implicit default)

Individual network filtering

titleAS-Path Stripping

The BGP route servers do not add their own ASN in the advertised path, so if you're planning on constructing a filter list to filter the BGP Route servers, do not use the BGP route servers ASN in the path!

We do not yet publish a route object for the route-servers.  We will add that in the future, so, for now, please reach out to the Ops team to see how to do this most efficiently.

Prefixes auto-filtered by the Route Servers

For the overall safety and security of our participants, we actively filter the following prefixes at the Route Servers.  That is, advertisements from peers, containing the following networks, will be dropped, and not onward announced.

Code Block
titleIPv4 prefixes filtered by the BGP-RS (RFC6890)
        martians = [

Code Block
titleIPv6 prefixes filtered by the BGP-RS
        martians = [
                ::/0,                   # Default (can be advertised as a route in BGP to peers if desired)
                ::/96,                  # IPv4-compatible IPv6 address - deprecated by RFC4291
                ::/128,                 # Unspecified address
                ::1/128,                # Local host loopback address
                ::ffff:,     # IPv4-mapped addresses
                ::,       # Compatible address (IPv4 format)
                ::,       # Compatible address (IPv4 format)
                ::,         # Compatible address (IPv4 format)
                ::,       # Compatible address (IPv4 format)
                0000::/8+,              # Pool used for unspecified, loopback and embedded IPv4 addresses
                0200::/7+,              # OSI NSAP-mapped prefix set (RFC4548) - deprecated by RFC4048
                3ffe::/16+,             # Former 6bone, now decommissioned
                2001:db8::/32+,         # Reserved by IANA for special purposes and documentation
                2002:e000::/20+,        # Invalid 6to4 packets (IPv4 multicast)
                2002:7f00::/24+,        # Invalid 6to4 packets (IPv4 loopback)
                2002:0000::/24+,        # Invalid 6to4 packets (IPv4 default)
                2002:ff00::/24+,        # Invalid 6to4 packets
                2002:0a00::/24+,        # Invalid 6to4 packets (IPv4 private network)
                2002:ac10::/28+,        # Invalid 6to4 packets (IPv4 private network)
                2002:c0a8::/32+,        # Invalid 6to4 packets (IPv4 private network)
                fc00::/7+,              # Unicast Unique Local Addresses (ULA) - RFC 4193
                fe80::/10+,             # Link-local Unicast
                fec0::/10+,             # Site-local Unicast - deprecated by RFC 3879 (replaced by ULA)
                ff00::/8+,              # Multicast
                ::/0{49,128}            # Filter small prefixes

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