Easynet BGP Policy Description
$Easynet: group/doc/groupnetwork/policy,v 1.34 2003/03/24 21:21:42 robert Exp $
See CVS logs for version history.

It is anticipated this document will be marked up into HTML form for
customer consumption.

This scheme was agreed on the system managers' meeting on 2002-10-29 in 
Brussel. The implementation deadline for incoming community tagging 
is 2002-12-01.


This document describes two aspects of BGP network control that can be
used to form policy decisions throughout the Easynet Group Network.

It has a number of purposes:

1) To allow Easynet networks and its' customers to use communities in
   order to control how prefixes are handled within the network when
   announcing to external parties.

2) To provide a coherent and conformant policy on BGP prefix management
   within the network.

3) To allow Easynet to increase the efficiency of its' use of external

It is divided into the following sections:

o  Description of communities

o  The use of communities in the Easynet network (both for
   classification and for control)

o  Description of local-preference



The notation used to represent community values splits the 32-bit
attribute into two 16-bit decimal numbers seperated by a single
colon `:'. Nominally, the left-hand value is an AS number and the
second is site defined.

There are some predefined community values that are common to all AS's.
Refer to RFC1997 and RFC1998 for more details on Communities.

Use of communities in the Easynet Network

There are two uses for communities in the Easynet network: Classification
of prefixes and control of prefixes.

Only Easynet itself classifies prefixes as they enter the network at
its' borders. Customers and peers should not do so. These attributes
can be used by multihomed downstreams to weight traffic in order to
distribute it according to local administrative policies. Prefixes
are classified according to geographic entry point, class of
prefix (Transit, Public Peering, Private Peering) and which
entity of each class (Specific Transit provider, Public Peering
point etc).

Prefix control allows the path-extension or filtering entirely of
customer prefixes where they are announced at the borders of Easynets'
network. Only class of network (Transit, Public Peering, Private
Peering) and/or class entity (Specific Transit provider, specific
Public Peering point etc) can be targeted.

As a matter of policy, the AS number used for all community strings
is AS4589. This allows for consistency across the network.

There are four classes of communities, identified by the number of
digits in the right-hand side:

  o 1 digit
    prefix classification by distributation range

  o 3 digits
    prefix classification by peer or NAP from which it was received

  o 4 digits
    outgoing announcement control

  o 5 digits
    prefix classification by location at which it was received

In addition to the communities listed below, the well-known
communities (local-AS, no-advertise and no-export) are recognised and
can be used (in fact, they're handled automatically by the routers).

One-digit communities

These communities are set by Easynet upon entry on the network. They
indicate how far a prefix should be distributed. The following
communities are used:

  o 4589:1
    Easynet or customer network.
    Unless specifically supressed by other means, this prefix will be 
    announced everywhere, including upstreams and peers. For a prefix
    to get transit, it MUST have this community set on it.

  o 4589:2
    Global network.
    This is a prefix that is visible in the DFZ (default free zone), e.g.
    routes received from peers or from upstreams. This is also set on
    customer routes.

  o 4589:3
    Confederation network.
    This prefix is visible only within the AS4589 confederations. Examples
    include the IPv6 suballocations or the SAP "extranet" prefix. Normally
    these prefixes will have no-export set too.

  o 4589:4
    Subconfederaton-local network.
    This prefix will be restricted to one subconfederation, e.g. AS65044.
    Customer prefixes held in BGP will have this community. Normally these
    prefixes will have local-AS/no-export-subconfed set too.

Two-digit communities

Currently unused. In future it might for example be used to control

Three-digit communities

Prefixes coming from peers and transit will be tagged with three-digit
community values, e.g. a prefix received at DECIX will be tagged with
4589:641. Only the most specific community is added, e.g. a route from
DECIX will not have 4589:640 set.

	Community	Entry point
	4589:5xx	External Transit
	4589:520	unused (was Teleglobe AS6453)
	4589:530	Genuity US (AS1)
	4589:531	Genuity DE (AS7176)
	4589:540	Cable & Wireless US (AS3561)
	4589:541	Cable & Wireless UK (AS3561)
	4589:542	Cable & Wireless DE (AS1273)
	4589:550	unused (was KPNQwest AS286, formerly Ebone AS1755)
	4589:560	Sprint IT
        4589:565	Level 3 DE (AS3356)
	4589:570	Telia FR (AS1299)
	4589:580	InfoNet NL (AS3300)
	4589:59x	Special IPv6 transit
	4589:591	Cable & Wireless DE (AS3561)

	4589:6xx	From an IXP/NAP peer
	4589:61x	From UK NAPs
	4589:611	From LINX (AS65000 - Int'l)
	4589:612	From LINX (AS65044 - UK)
	4589:613	From LoNAP
	4589:614	From MaNAP
	4589:615	From Scotix
	4589:62x	From BE NAPs
	4589:621	From BNIX
	4589:625	From ES NAPs
	4589:626	From ESPANIX
	4589:627	From CATNIX
	4589:63x	From NL NAPs
	4589:631	From AMS-IX
	4589:635	From CH NAPs
	4589:636	From TIX
	4589:637	From CERN/CIXP
	4589:64x	From DE NAPs
	4589:641	From DECIX
	4589:642	From MAE Frankfurt
	4589:643	From INXS Munich
	4589:644	From INXS Hamburg
	4589:645	From BCIX Berlin
	4589:65x	From FR NAPs
	4589:651	From SFINX
	4589:652	From MAE Paris
	4589:653	From FreeIX
	4589:654	From PARIX
	4589:66x	From IT NAPs
	4589:661	From MiX
	4589:662	From TopIX
	4589:670	From US NAPs
	4589:671	From NYIIX
	4589:672	From NY6IX

	4589:7xx	From a Private Peer
	4589:710	From a UK private peering
	4589:740	From a DE private peering

	[To be discussed
	4589:8xx	From a Distinguished Peer
	4589:801	From Telia (AS1299)

	[To be discussed
	4589:900	Tunneled IPv6 Peers
	4589:901	Tunneled IPv6 peer without transit
	4589:902	Tunneled IPv6 peer with (some) transit agreement

Four-digit communities

Customers can set four-digit communities to control where prefixes are
announced. The three-digit communities are used as a base for this and
prefixed by 1, 2, 3 or 9 to control prepending of the customer's
prefix on announcement to peers or transits on the specified location.

        1               Prepend announcement with "4589" on its AS-path
	2		Prepend announcement with "4589 4589"
	3		Prepend announcement with "4589 4589 4589"
	9		Filter announcement, i.e. don't announce

For example, setting the community 4589:9641 will have the effect that
the network on which it is set will not be announced to DE-CIX.

These communities may not be implemented in the whole network. When
used, it should be verified that the specific community is
honored. Otherwise you can request that it is implemented.

For a wider range, the "x" in the list of entry points can be replaced
by "0". So for example "4589:2640" will result in a prepend of length
two on all IXPs in Germany, and "4589:2500" has the effect of
prepending 4589 to all transits.

Five-digit communities

Every prefix has a five-digit community set which tells on which
location it was received. This community has the following format:


where  usually is the country code with possible additions or
modification, and  is a number for each of the POPs/locations in
the country.

	Community	Entry point
	4589:101xx	US
        4589:10101      60 Hudson Street (TelX, NYC) [hsnyc]
        4589:10102      25 Broadway (Telehouse, NYC) [bwnyc]

	4589:131xx	NL

	4589:132xx	BE
	4589:13200	Unspecified location (self-originated prefixes)
	4589:13201	gdbru (Gulledelle, Brussels)
	4589:13202	ixbru (InterXion, Brussels)
	4589:13203	bnbru (Belnet, Brussels)

	4589:133xx	FR

	4589:134xx	ES
	4589:13400	Unspecified location (self-originated prefixes)
	4589:13401	Mad (Alfonso XI) [almad]
	4589:13402	Madrid (ESPANIX, Colonia Banesto) [exmad]
	4589:13403	Barcelona (C&W, Pedrosa) [cwbcn]
	4589:13404	Barcelona (CATNIX, Cesca) [cxbcn]

	4589:139xx	IT
	4589:13900	Unspecified location (self-originated prefixes)
	4589:13901	Milan (Fulvio Testi 7) [ftmil]
	4589:13902	Milan (Via Caldera 22) [camil]
	4589:13903	Milan (Redbus) [rbmil]
	4589:13904	Milan (San Donato M.) [sdmil]
	4589:13905	Milan (MiX) [ixmil]
	4589:13906	Rome (Simone Martini) [smrom]

	4589:141xx	CH
	4589:14100	Unspecified location (self-originated prefixes)
	4589:14101	Zuerich (Hardturmstrasse 135) [htzrh]
	4589:14102	Zuerich (TIX, Telehouse) [thzrh]
	4589:14103	Geneva (CIXP, Telehouse) [thgva]

	4589:144xx	UK
        4589:14411      London (44 Whitfield) [wslon]
        4589:14412      London (39 Whitfield) (deprecated)
        4589:14413      London (Telehouse) [thlon]
        4589:14414      London (Telecity) [tclon]
        4589:14415      London (1 Brick Lane) [bllon]
        4589:14416      London (Slough)
	4589:14417	London (Redbus - Harbour Exchange)
	4589:14418	London (Redbus - Meridian Gate
	4589:14419	London (Redbus - Sovereign House)
	4589:14420	London (InterXion)
	4589:14431	Scotland (Scolocate Edinburgh)
	4589:14432	Scotland (Easynet Edinburgh)
	4589:peering, apart from 4589:xxxx from customers which they can use to
control announcements.

All other communities are accepted and passed unchanged.


BGP Local Preference

Local Preferences:

	150		Customer or Easynet route, learnt directly
	100		Normal transit/peer route
	50		Low preference Transit Route

Legacy Communities

The communities listed here were used previously and will be phased out.

        Community       Entry point
        11341:1         Easynet or Customer network

        11341:10        UK
        11341:11        London (44 Whitfield) [wslon]
        11341:12        London (39 Whitfield) (deprecated)
        11341:13        London (Telehouse) [thlon]
        11341:14        London (Telecity) [tclon]
        11341:15        London (1 Brick Lane) [bllon]
        11341:16        London (Slough)
        11341:20        UK National Network
        11341:21        Manchester (Telecity) [tcman]

        11341:30        DE
        11341:31        Frankfurt (WCOM/MAE Frankfurt) [mafra]
        11341:32        Frankfurt (DECIX) [ixfra]
        11341:33        Frankfurt (NT Telehouse) [ttfra]
        11341:34        Munich (INXS/ECRC) [ixmuc]
        11341:35        Hamburg (NT Telcotrust) [ttham]
        11341:36        Berlin (NT Telcotrust) [ttber]
        11341:37        Hamburg (C&W, INXS) [ixham]

        11341:40        US
        11341:41        60 Hudson Street (TelX, NYC) [hsnyc]
        11341:42        25 Broadway (Telehouse, NYC) [bwnyc]

        11341:50        FR
        11341:51        Paris (Telehouse) [thpar]
        11341:52        Parid (Beaubourg) [bbpar]

        11341:60        BE
        11341:61        Brussels Office [gdbru]
        11341:62        Brussels (Belnet) [bnbru]
        11341:63        Brussels (InterXion) [ixbru]

        11341:70        NL
        11341:71        Amsterdam (Level 3) [l3ams]
        11341:72        Amsterdam (Telecity) [tcams]
        11341:73        Amsterdam (Hoofddorp) [enhfd]

        11341:80        ES
        11341:81        Madrid (Alfonso XI) [almad]
        11341:82        Madrid (Espanix)
        11341:82        Madrid (Redbus)
        11341:85        Barcelona (Cable & Wireless)
        11341:86        Barcelona (Catnix)
        11341:90        CH
        11341:91        Zurich Office [htzur]
        11341:92        Zurich (TIX)
        11341:95        Geneva (Office)
        11341:96        Geneva (Telehouse)
        11341:97        Geneva (CERN)

        11341:100       IT
        11341:101       Milan Office [ftmil]
        11341:102       Milan (MiX)
        11341:103       Milan (Redbus)
        11341:105       Rome (Colt)

        11341:n500      From external Transit
        11341:n520      From Teleglobe
        11341:n530      From Genuity 
        11341:n540      From Cable & Wireless
        11341:n550      From KPNQwest [was Ebone]
        11341:n560      From ECRC

        11341:n600      From an IXP/NAP peer
        11341:n610      From UK NAPs
        11341:n611      From LINX (AS11341)
        11341:n612      From LINX (AS5607)
        11341:n613      From LoNAP
        11341:n614      From MaNAP
        11341:n615      From Scotix
        11341:n620      From BE NAPs
        11341:n621      From BNIX
        11341:n625      From ES NAPs
        11341:n626      From ESPANIX
        11341:n627      From CATNIX
        11341:n630      From NL NAPs
        11341:n631      From AMS-IX
        11341:n635      From CH NAPs
        11341:n636      From TIX
        11341:n637      From CERN/CIXP
        11341:n640      From DE NAPs
        11341:n641      From DECIX
        11341:n642      From MAE Frankfurt
        11341:n643      From INXS Munich
        11341:n644      From INXS Hamburg
        11341:n650      From FR NAPs
        11341:n651      From SFINX
        11341:n652      From MAE Paris
        11341:n653      From FreeIX
        11341:n654      From PARIX
        11341:n660      From IT NAPs
        11341:n661      From MIIX
        11341:n670      From US NAPs
        11341:n671      From NYIIX

        11341:n700      From a Private Peer
        11341:n701      From AboveNET (AS6461)
        11341:n702      From DTAG (AS3320)

Where a community specifies "n", replace "n" with the appropriate

                 Classification, for inbound prefixes
        1               Filter announcement, for outbound prefixes
        2               Prepend announcement with "11341 11341 11341" on
                        its AS-path, for outbound prefixes

For example, prefixes that match community "11341:60" will have entered
the Easynet network in Brussels. Prefixes that also match "11341:621"
will have entered the network at BNIX, a Brussels-based Public Peering

If you set "11341:1620" on a prefix then that prefix will not be announced
to any peers as Public Peering points in Belgium. "11341:2621" would
result in the AS-path of your prefix having "11341 11341 11341" prepended
to it.

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