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BGP COMMUNITIES

Internet, Optimized

1. Introduction

  • This document describes the BGP communities which are used by GTT (AS3257).
  • These communities can be used for their pure informational value and/or to modify the behavior of the routing service provided by AS3257.

2. Egress Communities

  • These are communities which are relayed from AS3257 to their peers.

2.1 Origin Communities

2.1.1 General

Value Description
3257:4000 tags a GTT customer route.
3257:5000 a GTT originated route.

2.1.1.1 Accounting

Value Description
3257:6001 temporary dbb class 1 (allocation policy to be defined)
3257:6002 temporary dbb class 2 (allocation policy to be defined)
3257:6003 temporary dbb class 3 (allocation policy to be defined)
3257:6004 temporary dbb class 4 (allocation policy to be defined)
3257:6005 temporary dbb class 5 (allocation policy to be defined)

2.1.2 Exchanges

Value Description
3257:4400-4499 tags EU exchange points (details upon request).
3257:4500-4599 tags US exchange points (details upon request).

2.1.3 Geographical

Value Description
3257:50001 route originated in Europe
3257:50002 route originated in the US and Canada
3257:50003 route originated in Asia
3257:50100 Regions by route miles
3257:50110 route originated in central Europe
3257:50111 route originated in outer Europe
3257:50120 route originated in US east coast
3257:50121 route originated in US west coast
3257:50122 route originated in US Canada outer regions
3257:50130 route originated in Asia
3257:51100 route originated in the US east coast
3257:51101 route originated in NYC
3257:51102 route originated in WAS
3257:51103 route originated in MIA
3257:51104 route originated in ATL
3257:51105 route originated in BOS
3257:51106 route originated in PHI
3257:51107 route originated in CHA
3257:51108 route originated in ORL
3257:51200 route originated in the US west coast
3257:51201 route originated in SJC
3257:51202 route originated in LAX
3257:51203 route originated in PAO
3257:51204 route originated in SEA
3257:51205 route originated in PHX
3257:51206 route originated in LAS
3257:51207 route originated in SLC
3257:51300 route originated in the US central
3257:51301 route originated in CHI
3257:51302 route originated in DAL
3257:51303 route originated in DEN
3257:51304 route originated in STL
3257:51305 route originated in MIN
3257:51306 route originated in IAH
3257:51400 route originated in Canada
3257:51401 route originated in TOR
3257:51402 route originated in MTL
3257:51403 route originated in VAN
3257:53000 route originated in GR
3257:53001 route originated in ATH
3257:53100 route originated in NL
3257:53101 route originated in AMS
3257:53200 route originated in BE
3257:53201 route originated in BRU
3257:53202 route originated in ANR
3257:53300 route originated in FR
3257:53301 route originated in PAR
3257:53302 route originated in MRS
3257:53400 route originated in ES
3257:53401 route originated in MAD
3257:53402 route originated in BCN
3257:53520 route originated in LU
3257:53530 route originated in IE
3257:53531 route originated in DUB
3257:53590 route originated in BG
3257:53591 route originated in SOF
3257:53700 route originated in LT
3257:53701 route originated in VIL
3257:53900 route originated in IT
3257:53901 route originated in TRN
3257:53902 route originated in MIL
3257:53903 route originated in BLQ
3257:53904 route originated in ROM
3257:53905 route originated in CAG
3257:53906 route originated in PSR
3257:53907 route originated in FLR
3257:53908 route originated in GOA
3257:53909 route originated in NAP
3257:53910 route originated in PMO
3257:53911 route originated in QPA
3257:54000 route originated in RO
3257:54001 route originated in BUC
3257:54100 route originated in CH
3257:54101 route originated in ZUR
3257:54102 route originated in BSL
3257:54200 route originated in CZ
3257:54201 route originated in PRG
3257:54210 route originated in SK
3257:54211 route originated in BTS
3257:54300 route originated in AT
3257:54301 route originated in VIE
3257:54400 route originated in UK
3257:54401 route originated in LON
3257:54402 route originated in MAN
3257:54500 route originated in DK
3257:54501 route originated in CPH
3257:54600 route originated in SE
3257:54601 route originated in STK
3257:54700 route originated in NO
3257:54701 route originated in OSL
3257:54800 route originated in PL
3257:54801 route originated in WAW
3257:54900 route originated in DE
3257:54901 route originated in FRA
3257:54902 route originated in DUS
3257:54903 route originated in HAM
3257:54904 route originated in MUC
3257:54905 route originated in BER
3257:56500 route originated in SG
3257:56501 route originated in SIN
3257:56600 route originated in JP
3257:56601 route originated in TYO
3257:58520 route originated in HK (Hong Kong)
3257:58521 route originated in HKG
3257:59000 route originated in TR
3257:59001 route originated in IST
3257:50999 multi-national prefix (not applicable, legacy)

2.1.4 Private Interconnect

Value Description
3257:30000-39999 Auto-incremental number of private interconnects

2.1.5 Loopbacks

Last digits of the loopback IP address from the router receiving the prefix.

Value Description
3257:8000-8999 loopback IP address

2.1.5 Loopbacks

Last digits of the loopback IP address from the router receiving the prefix.

Value Description
3257:8000-8999 loopback IP address

2.2 Traffic Engineering Communities

3. Ingress Communities

  • Communities which are relayed from the peers to AS3257. Prior to activation of community announcement, it is needed to send an email to [email protected] describing the specific bgp session(s) and intended communities to ensure proper activation on the GTT equipment.

3.1 Restricted Route Propagation

3.1.1 Well-known Communities

  • AS3257 supports the use of well-known communities as defined in IETF RFC1997 and RFC3765.
Value Description
65535:65281 NO_EXPORT (RFC1997)
65535:65282 NO_ADVERTISE (RFC1997)
65535:65283 NO_EXPORT_SUBCONFED (RFC1997)
65535:65284 NOPEER (RFC3765)

3.1.2 Do Not Announce

The below communities can be used to deny announcements to GTT’s peering partners only. They will not work for GTT’s customers.

Value Description
3257:2590 do not announce in Asia (only applies to Asia regional peers).
3257:2990 do not announce in the US (only applies to US regional peers).
3257:2998 do not announce to any peer (legacy)
65000:XXXX do not announce to ASXXXX
65010:XXXX do not announce except to ASXXXX
65535:65284 do not announce to any peer

3.2 Attribute Change

3.2.1 Prepends

The below communities can be used to prepend announcements to GTT’s peering partners only. They will not work for GTT’s customers.

Value Description
3257:2291 prepend 1x to any peering partner
3257:2292 prepend 2x to any peering partner
3257:2293 prepend 3x to any peering partner
3257:2491 prepend 1x in Europe (only applies to EU regional peers).
3257:2492 prepend 2x in Europe (only applies to EU regional peers).
3257:2493 prepend 3x in Europe (only applies to EU regional peers).
3257:2591 prepend 1x in Asia (only applies to Asia regional peers).
3257:2592 prepend 2x in Asia (only applies to Asia regional peers).
3257:2593 prepend 3x in Asia (only applies to Asia regional peers).
3257:2991 prepend 1x in the US (only applies to US regional peers).
3257:2992 prepend 2x in the US (only applies to US regional peers).
3257:2993 prepend 3x in the US (only applies to US regional peers).
65001:XXXX prepend 1x to ASXXXX
65002:XXXX prepend 2x to ASXXXX
65003:XXXX prepend 3x to ASXXXX

3.2.2 Local Preference

Value Description
3257:1980 give routes localpref below normal customer route.
3257:1970 give routes localpref below normal peer route.

3.3 Blackholing

  • Please check with our team at [email protected] first, if this is enabled for your session.
Value Description
3257:2666 blackhole (discard) traffic

APPENDIX

3A.1 Ascending List of 3257:XXXX communities

Value Description
3257:2000-2999 Customer Control
3257:4000-5000 Route purpose
3257:6000-6999 Accounting (engineering internal use only)
3257:7000-7999 restricted route distribution (engineering internal use only)
3257:8000-8999 receiving router loopback IP address
3257:9000-9999 restricted route distribution (engineering internal use only)
3257:10000-19999 Private Interconnect egress filtering (engineering internal use only)
3257:30000-39999 Private Interconnect ingress tagging
3257:50000-59999 Geographic origin tagging

OUR GARTNER RATING

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4.2


62 Reviews

88%
as of the last 12 months

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