BGP Community String for Savvis Communications AS3561

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Savvis AS3561

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1. SAVVIS Received BGP Community Attribute Values (BGP community String)

SAVVIS Prepend/Suppression BGP Community Attribute Values (3561:30PPN)

SAVVIS allows customers to control certain traffic flows off-net with the implementation of BGP community attribute values that prepend route/prefix paths with additional AS hops. These BGP community attribute values, which the customer applies, affects the way SAVVIS peers choose the degree of preference of a given prefix/route, because the number of AS hops within the route-path has been lengthened.

The format for the second component of customer route BGP community number (after 3561:) is set at five digits. This fixed length allows regular expressions to be used in applying a defined number of prepends to a given route/prefix path. This format is 3561:30PPN, where the fields are coded in the following way. (Note: The first 2 digits of the second component are always "30" then followed by variables of the "PP" and "N" variables which are defined in the following tables.)

The "PP" variable cross references peers of SAVVIS, defined in the following table. (Note, this will always be a two digit value.)

PP Code	Peer Name	Peer AS Number
00	All Peers	-
01	SBC	AS7132
02	Sprint	AS1239
03	Tiscali	AS3257
04	Qwest	AS209
06	Verio/NTT	AS2914
07	Level3	AS3356
08	GlobalCrossing	AS3549
09	FranceTelecom	AS5511
10	WilliamsCommunicationsGroup	AS7911
11	DeutscheTelekomAG	AS3320
12	XOCommunications	AS2828
13	AboveNet/MFN	AS6461
14	UUNet	AS701
15	AT&T	AS7018
18	Cogent	AS174
21	ATDN	AS1668
41	Colt	AS8220
43	Infonet	AS3300
44	UUNet-EU	AS702
46	Telia	AS1299

The "N" variable cross references the number of prepends, defined in the following table. Please note, the only valid "N" value for all peers (PP code 00) is 0 (Do not export).

N Values

"N" Value Meaning

0 Do not export
1 Prepend once
2 Prepend twice
3 Prepend three times
9 Announce-only

Examples:

3561:30030 Do not export this route to PSINet (AS174)
3561:30142 Prepend this route twice, to UUNet (AS701)
3561:30159 Announce this route only to AT&T (AS7018)
SAVVIS Blackhole BGP Community Attribute Values (3561:666)

For customers that have a host or block under a DDoS, the affected host/block can be advertised to AS3561 with BGP community string 3561:666. This will cause all traffic to that host to be black-holed at the core of the AS3561 network. This action will trigger emails sent to the appropriate security and operations groups for notification purposes.

After advertising the prefix with 3561:666, the customer should open a priority one incident report with Client Services:

SAVVIS Support Center (SSC)

Phone: 888-638-6771

email: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it

Once the attack has been mitigated, the customer will be responsible for removing the prefix from being advertised.

SAVVIS will not be held responsible for customers who errantly advertise prefixes with the blackhole BGP community string.

SAVVIS Received BGP Community Attribute Values

Value: 3561:70
Definition:Sets local preference value within AS3561 to "70".

Value: 3561:80
Definition:Sets local preference value within AS3561 to "80".

Value: 3561:90
Definition:Sets local preference value within AS3561 to "90".

Value: 3561:no-export or 3561:no-advertise
Definition: Will prevent the network/prefix tagged with this (either) BGP community attribute from being announced outside AS3561. Note, this will prevent the route from being propagated to SAVVIS eBGP customers receiving a routing table.

2. SAVVIS Announced BGP Community Attribute Values

Formerly, only two SAVVIS BGP community attribute values were announced to users upon request: 3561:900 (customer routes) and 3561:999 (peer routes). These have been replaced by a new BGP community string implementation.

The new implementation allows for a 5 digit string, following the "3561:" notation. Each bit/digit has a pertinent value and meaning represented in the following tables (3561:xxxxx)

This was facilitated to provide the following routing information to customers receiving a routing table from SAVVIS via eBGP routing.

Identification of route source by a. Customer or peer b. Region - Predefined by SAVVIS - Based upon physical connection point c. Country - Predefined by SAVVIS - Based upon physical connection point

The format for the second component of customer route BGP community number (after 3561:) is set at five digits. This fixed length allows regular expressions to be used in routing policy statements to select subsets of customer routes. This format is 3561:SRCCC where the fields are coded in the following way.

"S" refers to 'source' of the route: Source Codes Code Source 1 Customer 2 Peer Example: 3561:1xxxx customer route 3561:2xxxx peer route

"R" defines the region, as specified in Table 3-1. Codes 7 through 0 that are not defined yet and thus available for future region definitions. Since there are only four available region codes left, the definition of each code shall await a need for the function it would provide.

Regional Codes Code Region 1 North America (U.S.A and Canada) 2 Europe 3 Asia (including Japan) 4 Australia 5 South America 6 Middle East 7 Available for future region definitions 8 Available for future region definitions 9 Available for future region definitions 0 Available for future region definitions Example: 3561:11xxx customer, North America 3561:24xxx peer, Australia

"CCC" signifies country code defined by ISO 3166 codes for countries. Note: Peers use a country code of "000".

Example: 3561:11840 customer, North America, United States
3561:22000 peer, Europe, Italy

Country Country Abbr. CCC Code

AFGHANISTAN AF 004
ALBANIA AL 008
ALGERIA DZ 012
AMERICAN SAMOA AS 016
ANDORRA AD 020
ANGOLA AO 024
ANGUILLA AI 660
ANTARCTICA AQ 010
ANTIGUA AND BARBUDA AG 028
ARGENTINA AR 032
ARMENIA AM 051
ARUBA AW 533
AUSTRALIA AU 036
AUSTRIA AT 040
AZERBAIJAN AZ 031
BAHAMAS BS 044
BAHRAIN BH 048
BANGLADESH BD 050
BARBADOS BB 052
BELARUS BY 112
BELGIUM BE 056
BELIZE BZ 084
BENIN BJ 204
BERMUDA BM 060
BHUTAN BT 064
BOLIVIA BO 068
BOSNIA AND HERZEGOWINA BA 070
BOTSWANA BW 072
BOUVET ISLAND BV 074
BRAZIL BR 076
BRITISH INDIAN OCEAN TERRITORY IO 086
BRUNEI DARUSSALAM BN 096
BULGARIA BG 100
BURKINA FASO BF 854
BURUNDI BI 108
CAMBODIA KH 116
CAMEROON CM 120
CANADA CA 124
CAPE VERDE CV 132
CAYMAN ISLANDS KY 136
CENTRAL AFRICAN REPUBLIC CF 140
CHAD TD 148
CHILE CL 152
CHINA CN 156
CHRISTMAS ISLAND CX 162
COCOS (KEELING) ISLANDS CC 166
COLOMBIA CO 170
COMOROS KM 174
CONGO CG 178
CONGO, THE DEMOCRATIC REPUBLIC OF THE CD 180
COOK ISLANDS CK 184
COSTA RICA CR 188
COTE D'IVOIRE CI 384
CROATIA (local name: Hrvatska) HR 191
CUBA CU 192
CYPRUS CY 196
CZECH REPUBLIC CZ 203
DENMARK DK 208
DJIBOUTI DJ 262
DOMINICA DM 212
DOMINICAN REPUBLIC DO 214
EAST TIMOR TP 626
ECUADOR EC 218
EGYPT EG 818
EL SALVADOR SV 222
EQUATORIAL GUINEA GQ 226
ERITREA ER 232
ESTONIA EE 233
ETHIOPIA ET 231
FALKLAND ISLANDS (MALVINAS) FK 238
FAROE ISLANDS FO 234
FIJI FJ 242
FINLAND FI 246
FRANCE FR 250
FRANCE, METROPOLITAN FX 249
FRENCH GUIANA GF 254
FRENCH POLYNESIA PF 258
FRENCH SOUTHERN TERRITORIES TF 260
GABON GA 266
GAMBIA GM 270
GEORGIA GE 268
GERMANY DE 276
GHANA GH 288
GIBRALTAR GI 292
GREECE GR 300
GREENLAND GL 304
GRENADA GD 308
GUADELOUPE GP 312
GUAM GU 316
GUATEMALA GT 320
GUINEA GN 324
GUINEA-BISSAU GW 624
GUYANA GY 328
HAITI HT 332
HEARD AND MC DONALD ISLANDS HM 334
HOLY SEE (VATICAN CITY STATE) VA 336
HONDURAS HN 340
HONG KONG HK 344
HUNGARY HU 348
ICELAND IS 352
INDIA IN 356
INDONESIA ID 360
IRAN (ISLAMIC REPUBLIC OF) IR 364
IRAQ IQ 368
IRELAND IE 372
ISRAEL IL 376
ITALY IT 380
JAMAICA JM 388
JAPAN JP 392
JORDAN JO 400
KAZAKHSTAN KZ 398
KENYA KE 404
KIRIBATI KI 296
KOREA, DEMOCRATIC PEOPLE'S REPUBLIC OF KP 408
KOREA, REPUBLIC OF KR 410
KUWAIT KW 414
KYRGYZSTAN KG 417
LAO PEOPLE'S DEMOCRATIC REPUBLIC LA 418
LATVIA LV 428
LEBANON LB 422
LESOTHO LS 426
LIBERIA LR 430
LIBYAN ARAB JAMAHIRIYA LY 434
LIECHTENSTEIN LI 438
LITHUANIA LT 440
LUXEMBOURG LU 442
MACAU MO 446
MACEDONIA, FORMER YUGOSLAV REPUBLIC OF MK 807
MADAGASCAR MG 450
MALAWI MW 454
MALAYSIA MY 458
MALDIVES MV 462
MALI ML 466
MALTA MT 470
MARSHALL ISLANDS MH 584
MARTINIQUE MQ 474
MAURITANIA MR 478
MAURITIUS MU 480
MAYOTTE YT 175
MEXICO MX 484
MICRONESIA, FEDERATED STATES OF FM 583
MOLDOVA, REPUBLIC OF MD 498
MONACO MC 492
MONGOLIA MN 496
MONTSERRAT MS 500
MOROCCO MA 504
MOZAMBIQUE MZ 508
MYANMAR MM 104
NAMIBIA NA 516
NAURU NR 520
NEPAL NP 524
NETHERLANDS NL 528
NETHERLANDS ANTILLES AN 530
NEW CALEDONIA NC 540
NEW ZEALAND NZ 554
NICARAGUA NI 558
NIGER NE 562
NIGERIA NG 566
NIUE NU 570
NORFOLK ISLAND NF 574
NORTHERN MARIANA ISLANDS MP 580
NORWAY NO 578
OMAN OM 512
PAKISTAN PK 586
PALAU PW 585
PALESTINIAN TERRITORY, OCCUPIED PS 275
PANAMA PA 591
PAPUA NEW GUINEA PG 598
PARAGUAY PY 600
PERU PE 604
PHILIPPINES PH 608
PITCAIRN PN 612
POLAND PL 616
PORTUGAL PT 620
PUERTO RICO PR 630
QATAR QA 634
REUNION RE 638
ROMANIA RO 642
RUSSIAN FEDERATION RU 643
RWANDA RW 646
SAINT KITTS AND NEVIS KN 659
SAINT LUCIA LC 662
SAINT VINCENT AND THE GRENADINES VC 670
SAMOA WS 882
SAN MARINO SM 674
SAO TOME AND PRINCIPE ST 678
SAUDI ARABIA SA 682
SENEGAL SN 686
SEYCHELLES SC 690
SIERRA LEONE SL 694
SINGAPORE SG 702
SLOVAKIA (Slovak Republic) SK 703
SLOVENIA SI 705
SOLOMON ISLANDS SB 090
SOMALIA SO 706
SOUTH AFRICA ZA 710
SOUTH GEORGIA & SOUTH SANDWICH ISLANDS GS 239
SPAIN ES 724
SRI LANKA LK 144
ST. HELENA SH 654
ST. PIERRE AND MIQUELON PM 666
SUDAN SD 736
SURINAME SR 740
SVALBARD AND JAN MAYEN ISLANDS SJ 744
SWAZILAND SZ 748
SWEDEN SE 752
SWITZERLAND CH 756
SYRIAN ARAB REPUBLIC SY 760
TAIWAN, PROVINCE OF CHINA TW 158
TAJIKISTAN TJ 762
TANZANIA, UNITED REPUBLIC OF TZ 834
THAILAND TH 764
TOGO TG 768
TOKELAU TK 772
TONGA TO 776
TRINIDAD AND TOBAGO TT 780
TUNISIA TN 788
TURKEY TR 792
TURKMENISTAN TM 795
TURKS AND CAICOS ISLANDS TC 796
TUVALU TV 798
UGANDA UG 800
UKRAINE UA 804
UNITED ARAB EMIRATES AE 784
UNITED KINGDOM GB 826
UNITED STATES US 840
UNITED STATES MINOR OUTLYING ISLANDS UM 581
URUGUAY UY 858
UZBEKISTAN UZ 860
VANUATU VU 548
VENEZUELA VE 862
VIET NAM VN 704
VIRGIN ISLANDS (BRITISH) VG 092
VIRGIN ISLANDS (U.S.) VI 850
WALLIS AND FUTUNA ISLANDS WF 876
WESTERN SAHARA EH 732
YEMEN YE 887
YUGOSLAVIA YU 891
ZAMBIA ZM 894
ZIMBABWE ZW 716

Applying BGP Community string with sample configuration

1. Get the latest BGP community string from your ISP/upstream provider or check new.CiscoNET.com web site.

2. Pick the best BGP community string for your traffic shaping plan (mainly incoming traffic). Most of ISPs are providing BGP community string with local preference and AS prepending option. Cannot tell which one is better than the other. It will depend on your global traffic shaping plan.

3. Follow the below commands ( Cisco only )

The below Sample configuration will tag the 10.0.0.0/24 route with [ISP AS]:120 or [ISP AS]:3 and will not tag any other routes.

router#config t
router(config)#ip bgp-community new-format
router(config)#access-list 10 permit 10.0.0.0 0.0.0.255
router(config)#access-list 10 deny any

router(config)#route-map [to-ISP] permit 10
router(config-route-map)#match ip address 10
router(config-route-map)#set community [ISP AS]:120 <---- using Local Preference

router(config-route-map)#set community [ISP AS]:3 <------- using AS prepending
router(config-route-map)#route-map [to-ISP] permit 20
router(config-route-map)#exit

router(config)#router bgp [xxxx] <------------------------------- xxxx = customer's ASN
router(config-router)#neighbor x.x.x.x send-community
router(config-router)#neighbor x.x.x.x route-map [to-ISP] out
router(config-router)#exit
router(config)#exit
router#copy running-config startup-config

4. And then, go to www.CiscoNET.com and pick one of route server on the map to see your announcement. If you are using AS prepending option, you will see your AS prepends on route servers. Sometime you might not see your route with particular ISP path.
In most of case it might not be any routing problem, just the route path was dropped at somewhere by BGP best path selection scheme. Try Oregon route server, if you can see your route. The Oregon route server is providing many possible and available paths between BGP speakers and neighbors.
If you don't see your route on there? check other route servers and also check your
BGP configuration. You might need to contact your upstream provider to check what they are learning BGP route from you.

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