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
oute 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
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)
