This document has been extracted from User Guide V5.pdf.
Services/Features
Local Preference
All customer routes announced to Cogent will have a local pref of 130.
The customer can control the local preference for their announcements by using a community string that is passed to Cogent in the BGP session. The following table lists the community strings and the corresponding local preference that will be set when they are used.
| Community String | Local Pref | Effect |
| 174:10 | 10 | Set customer route local preference to 10 (below everything-least preferred) |
| 174:70 | 70 | Set customer route local preference to 70 (below peers) |
| 174:120 | 120 | Set customer route local preference to 120 (below customer default) |
| 174:125 | 125 | Set customer route local preference to 125 (below customer default) |
| 174:135 | 135 | Set customer route local preference to 135 (above customer default) |
| 174:140 | 140 | Set customer route local preference to 140 (above customer default) |
AS Padding
Customers with public AS numbers may pad their AS path to control the desirability of their connections. Customers with an assigned private AS number from Cogent may not pad their AS path. Cogent will ignore any padding of private AS numbers from customers.
No-Export
Customers can control the "no-export" settings of their routes with the following community strings:
| Community String | Effect |
| 174:970 | Do not send route to NA (North America) - not accepted in NA. |
| 174:971 | Do not send route to NA peers. |
| 174:975 | Set local preference to 10 in NA. |
| 174:980 | Do not send route to EU (Europe) - not accepted in EU. |
| 174:981 | Do not send route to EU peers. |
| 174:985 | Set local preference to 10 in EU. |
| 174:990 | Do not send route to BGP customers, or peers. |
| 174:991 | Do not send route to peers. |
Peer Controls
Effective on ALL peer, non-granular.
| Community String | Effect |
| 174:3000 | Do not announce. |
| 174:3001 | Prepend 174 1 time. |
| 174:3002 | Prepend 174 2 times. |
| 174:3003 | Prepend 174 3 times. |
Other Communities
Routes announced to customers by Cogent will have one of the following communities associated with them:
| Community String | Description |
| 174:21000 | Route is learned from NA (North America) non-customer. |
| 174:21001 | Route is NA internal or customer route. |
| 174:21100 | Route is learned from EU (Europe) non-customer. |
| 174:21101 | Route is a EU internal or customer route. |
