Optic Fusion

BGP Policy

Customer BGP Policy

  • Peers must be multi-homed, either multi-homed within Optic Fusion's network, or multi-homed with Optic Fusion and one or more other providers.
  • Customers must have a registered public AS number, unless they are multi-homing with Optic Fusion only.
  • Optic Fusion will use only BGP version 4.
  • Optic Fusion requires customers to use a MD5 authentication key for all BGP sessions.
  • Customer netblock announcements to Optic Fusion are limited to a /24 or smaller prefix.
  • Optic Fusion will not static route any netblocks to customers running BGP, unless those netblocks are part of Optic Fusion aggregates and are too small to be announced individually (prefix length greater than /24).
  • Optic Fusion strongly encourages customers to aggregate contiguous network announcements to the highest CIDR boundary.
  • Outbound network announcements should be filtered by applying explicit prefix and AS path filters, not exclusive. (i.e. AS filters should list your AS and AS paths you would like to announce and deny all others, instead of denying just the AS's of external peers).
  • Customers should configure filters that prevent the sending of routing information from your other service providers to Optic Fusion and vice versa.
  • Optic Fusion allows customers to perform autonomous system path prepending which effectively lengthens the as-path seen by BGP speaking routers for netblocks which the customer originates.
  • Optic Fusion offers several choices regarding the types of prefixes that are advertised to the customer: Default Route, Partial Routes, and Full Routes. Customers may choose based on their own requirements and router memory constraints.
  • Optic Fusion reserves the right to take action if a BGP session is causing routing problems. This may include, but is not limited to, imposing a filter change or temporary shutdown of the offending BGP session until the problem is corrected.
  • Optic Fusion reserves the right to set or convert any and all route filters and filter types at their own discretion to preserve network stability and route sanity.

Local Preferences

Optic Fusion's local preference policy uses the following values:

110 Preferred Customer Routes
100 Customer Routes
90 Backup Customer Routes
70 Peering Routes
50 ISP Routes
40 Backup Routes


Customers may send the following communities to modify BGP local preference given to networks announced to Optic Fusion.

30170:110 Set local pref to 110 (preferred customer route)
30170:90 Set local pref to 90 (backup customer route)
30170:40 Set local pref to 40 (backup route, lowest on network)
30170:666 Blackhole route (DoS / Discard)

Additionally, Optic Fusion supports the well-known communities no-export and no advertise.

Optic Fusion also marks all received advertisements with one of the following communities:

30170:500 Internal
30170:600 Learned from Customer
30170:700 Learned from Peer
30170:800 Learned from ISP