Routing Policy

This document describes the policy implemented at the borders of AS14525 to control the import and export of routing information with other autonomous systems.

The policies defined herein are designed to provide the highest feasible levels of security, stability and performance for our inter-connectivity with other network operators. Readers are encouraged to contact [email protected] if they have queries related to the information presented.

Finding Information

Stellar Technologies maintains up to date information in multiple publicly available datasources, including:

If this document, or the above locations do not contain the information you are looking for, or if any information contained therein appears to be inaccurate, please email [email protected].

Peering Relationships

The topological relationship of AS14525 to the external peers of AS14525 may be generally categorised into:

  • Customers: networks for which AS14525 provides transit to other Internet networks
  • Peers: networks with whom AS14525 exchanges routing information relating only to our respective customers
  • Transits: networks that provide transit to AS14525 to other Internet networks

These terms are used herein to describe the topological relationship between AS14525 and an adjacent network, and do not necessarily imply the existence of a particular commercial relationship.

The term "Non-customer" may be used to describe an interconnection relationship other than those with customers of AS14525.

AS14525 may have multiple distinct relationships with a given AS at different points of interconnection. Thus, polices described here as applying to particular types of interconnection relationship should be construed as applying only to those interconnections or peerings of that type, rather than to all adjacencies with a given AS.

Import and Export Policies

Some policies are implemented uniformly across all adjacencies, whilst others will vary according to the topological relationship between AS14525 and the adjacent networks.

Autonomous Systems

  • 14525
  • 395077

Stellar Technologies Inc. operates a two autonomous systems throughout our network. ASN 395077 is used for legacy transit relationships, and is primarily used by our Orion Cloud Services offering, while ASN 14525 is used for global interconnection. As it relates to routing policy, AS395077 is considered a standard customer of AS14525. All transit, peering, or IX adjacencies will be formed with AS14525, which provides downstream transit for AS395077.

BGP Protocol

AS14525 will exchange routing information for Internet networks with external peers using Border Gateway Protocol version 4 only.

Bogon Address Space

AS14525 will not accept routing information for, nor deliver IP packets addressed to or from, "Bogon" address space, including:

Prefix Length

AS14525 will accept routing information for IP prefixes conforming to minimum and maximum prefix-lengths as follows:

Address FamilyMin LengthMax Length
IPv48 bits24 bits
IPv616 bits48 bits

Special Purpose ASNs

BGP updates with ASNs belonging to the IANA Special Purpose AS Numbers Registry in the AS_PATH will be rejected by AS14525.

Single homed customers of AS14525 that do not qualify for the allocation of an ASN under the relevant RIR policies in force in their region will will be allocated an ASN by Stellar Technologies from the range reserved for private use (per RFC 6996) for the purposes of establishing eBGP peering with AS14525 only. Prefixes announced from such customers and advertised to other external peers will appear to originate from AS14525.

Ingress BGP Filtering

Prefix Filter Maintenance

Stellar Technologies makes use of RPSL data contained in the distributed IRR system to maintain per-neighbor AS filters for all customer and peer networks of AS14525.

Stellar Technologies maintains the following RPSL datasets which may be used to prefix filter adjacencies with AS14525:

  • as-set : AS-AS14525

Please note: The size of AS-AS14525 should not be used as an indicator of the number of routes that a non-customer peer should expect to receive.

Ingress prefix-lists are built by recursively resolving the appropriate as-set down to a list of member ASNs, and then searching for route or route6 objects with the origin attribute set to one of these ASNs. This process is repeated daily, and updated prefix-lists are installed on border routers at approximately 03:00 in the timezone local to each router.

Prefixes received from customers and peers are accepted only if a route or route6 object matching the advertised prefix and origin AS is found. Prefixes received are subjected to the other conditions described in this document, including minimum and maximum prefix length.

Maximum Prefixes Limits

Stellar Technologies sets limits on the maximum number of prefixes accepted from a given eBGP neighbor. When a reasonable suggested value is published in the PeeringDB, that value will be used. Otherwise, Stellar Technologies use its discretion to arrive at an appropriate value.

AS_PATH Filters

Stellar Technologies filters all eBGP adjacencies with customers and peers based on AS_PATH. All customer or peer routes must originate from their respective ASN, unless otherwise defined in a peer-specific agreement.

Egress BGP Filtering

Prefix Filtering Towards Customers

Definition

DFZ: Default Free Zone

AS14525 will advertise one or more of the following sets of prefixes towards its customer peers:

  1. Full DFZ Routes: All routes learned by Stellar Technologies from customer and non-customer peers according to the policies described herein.
  2. Default Route: A single route of last resort, i.e. 0.0.0.0/0 or ::/0, generated locally on the border router upon which the eBGP session with AS14525 is configured.
  3. Partial DFZ Routes: In the case of "partial transit" customers, a subset of the full DFZ routes, being those imported from non-customer peers within the defined scope of the relevant customer's service. In all cases, partial transit customers will be advertised all prefixes imported from other customers, regardless of their scope of service.

Prefix Filtering Towards Non-customers

Only routes that are originated by AS14525 or are imported from customer peers will be exported.

Peers wishing to set a sensible maximum-prefixes limit on sessions with AS14525 should refer to the 'IPv4 Prefixes' and 'IPv6 Prefixes' field in our record on PeeringDB.

Every attempt will be made to maintain consistent announcements of prefixes towards peers. However, advertisement of prefixes learned from customers may be suppressed at certain peering locations, or towards specific neighbor ASNs, as the result of traffic engineering communities received from customers, as described below.

To prevent the inadvertent advertisement of transit between non-customer networks, a BGP community will be appended on import to indicate that a prefix was imported from a customer peer, and only prefixes carrying such community will be exported to non-customer neighbors.

Route Selection and BGP Attribute Handling

Stellar Technologies maintains a publicly available looking-glass to inspect route selection towards external networks from the perspective of AS14525.

The following BGP attribute handling policies define the expected route selection, for traffic routed to and from AS14525.

Local Preference

Stellar Technologies sets the BGP LOCAL_PREF attribute on import according to the relationship of AS14525 to the adjacent neighbor or the type of route, as per the below table.

Where a range of values is indicated, other factors such as whether a peering crosses an IXP or PNI are used to select the eventual value. By default, the mid-range value will be used.

Route TypeDefault
Transit150
Public Peer200
Private Peer250
Customer350
Locally Originated450
Blackhole Routes999

Customers may send BGP communities to influence the export of their routes to non-customer peers. Such communities may be used to influence the LOCAL_PREF values of their prefixes relative to the AS14525 routing domain.

AS Path

By default, AS14525 will prepend a single instance of 14525 on export to all external neighbors. AS14525 will not modify the AS_PATH attribute of any route on import.

Customers may send BGP communities to influence the export of their routes to non-customer peers. Such communities may be used to prepend 14525 up to 3 times to selected groups of non-customer peers.

The above functionality is documented fully in BGP Communities.

Multi-exit Discriminators

On export of any route, AS14525 will set the MULTI_EXIT_DISC (MED) attribute to a value equal to the IGP cost to the NEXT_HOP address of the route (before any changes are made to NEXT_HOP on export).

Similarly, unless agreed otherwise in advance, AS14525 will set the MED of any routes received from any single-homed peers (customer and non-customer) to zero on import. Multi-homed peers may be requested to adjust the MED values on export to align with AS14525 policy logic.

Routes received from customers with a MED value set will be imported unmodified by AS14525, and the route with the lowest such value will be preferred for selection (provided all other path selection factors are equal).

BGP Communities

Stellar Technologies leverages BGP communities in the operation of the AS14525 network. Publicly relevant communities implemented in the AS14525 network are defined and documented here.

Changes & Updates

Where notice of an impending change is deemed necessary, Stellar Technologies will make every attempt to notify affected customers or peers if it is determined that any impact will occur in accordance with Change Control Procedures.

Stellar Technologies accepts no liability whatsoever for damages or losses suffered by third parties as a result of their reliance on the information contained herein. By making use of any of information contained herein, the user acknowledges and agrees to these conditions.