With all the recent talk about filtering, I figured now was a good time
to update my list of evil /24 announcers... There are currently over 63k
/24s out of 113k total unfiltered announcements (over 55%).
http://www.e-gerbil.net/ras/projects/ipaddr/amuck-071902.txt
This scan is done from the point of view of Williams (AS7911) transit, a
fairly "average" unfiltered view of around 113k routes. It's not perfect,
but it's pretty easy to go down the list and verify which ones are really
poluting the internet.
The reason these don't get picked up on other peoples "cidr scans" is
that they have "gaps", so they are not perfectly cidr-able. The reasons
for these announcements vary, including obvious incompetence and
cable/dsl companies without a "backbone" connecting their various POPs
announcing a /24 for each location to a single transit provider.
If I had more free time I would extend this analysis past /24s, but since
they're such a huge amount of polution it's a good place to start. If
someone wanted to do an analysis of routes from a common block with
identical attributes, I suspect they would find it a bigger cause of net
polution than multihomers punching holes.
For quick complaining, the top 10 offenders are:
ASN Name Reg'd Netblock Prefixes
--- ---- -------------- --------
6595 DoD Dependents Schools - Europe 204.218.0.0/15 236
22927 TELEFONICA DE ARGENTINA 168.226.0.0/16 167
7029 Alltel Information Services 166.102.0.0/16 128
7303 Telecom Argentina Stet-France 200.43.0.0/16 127
14654 Wayport 64.134.0.0/16 113
16473 Bell South 198.146.0.0/16 111
11492 Cable One 24.116.0.0/16 108
18687 MPower Communications 208.57.0.0/16 98
7132 Southwestern Bell 207.193.0.0/16 89
1580 Army HQ, 5th Signal Command 144.170.0.0/16 88
http://info.us.bb.verio.net/routing.html
Quote: "We do not announce prefixes longer than /24."
Then why do I have:
5 /25
2 /26
3 /27
3 /28
21 /29
*sigh* I guess we don't eat our own dogfood...
Searching for matching routes, use ^C to quit...
Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED
E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH S:SUPPRESSED
F:FILTERED
Prefix Next Hop Metric LocPrf Weight
Status
1 63.73.183.0/25 129.250.126.97 2 100 0
EF
AS_PATH: 2914 10910 10910 10910 10910 10910 10910 10910 10910
10910 8012
2 128.241.222.0/28 129.250.126.97 3 100 0
EF
AS_PATH: 2914 12008
3 168.143.110.0/28 129.250.126.97 3 100 0
EF
AS_PATH: 2914 12008
4 192.41.162.0/25 129.250.126.97 3 100 0
EF
AS_PATH: 2914 14745
5 198.107.213.8/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 11854 11854 11854 11854 11854 11854 11854
6 198.107.213.16/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 11853 11853 11853
7 198.107.213.24/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 12179
8 198.107.213.32/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 13790
9 198.107.213.40/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 10912 10912 10912
Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED
E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH S:SUPPRESSED
F:FILTERED
Prefix Next Hop Metric LocPrf Weight
Status
10 198.107.213.48/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 12180
11 198.107.213.56/29 129.250.126.97 2 100 0
EF
AS_PATH: 2914 10910 10910 10910 10910 10910 10910 10910 10910
10910
12 198.107.213.64/29 129.250.126.97 4 100 0
EF
AS_PATH: 2914 13789 13789 13789 13789 13789
13 198.107.213.72/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 12178
14 198.107.213.80/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 6993 6993 6993
15 198.107.213.88/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 10911 10911 10911
16 198.107.213.96/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 10913
17 198.107.213.104/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 13791 13791 13791 13791 13791 13791
18 198.107.213.112/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 13792 13792 13792 13792 13792 13792
Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED
E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH S:SUPPRESSED
F:FILTERED
Prefix Next Hop Metric LocPrf Weight
Status
19 198.107.213.120/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 12181
20 198.107.213.144/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 14742 14742 14742
21 198.107.213.152/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 14636 14636 14636 14636 14636 14636 14636
22 198.107.213.160/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 14743 14743 14743
23 198.107.213.168/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 14745
24 198.107.213.176/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 19024 19024 19024
25 204.27.124.128/25 129.250.126.97 3 100 0
EF
AS_PATH: 2914 21637
26 204.171.181.32/29 129.250.126.97 3 100 0
EF
AS_PATH: 2914 16821 16821 16821 16821
27 207.20.149.96/27 129.250.126.97 3 100 0
EF
AS_PATH: 2914 11189
Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED
E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH S:SUPPRESSED
F:FILTERED
Prefix Next Hop Metric LocPrf Weight
Status
28 207.20.172.128/26 129.250.126.97 3 100 0
EF
AS_PATH: 2914 19359
29 207.174.18.128/27 129.250.126.97 3 100 0
EF
AS_PATH: 2914 13790 3404 19129
30 208.239.6.64/26 129.250.126.97 3 100 0
EF
AS_PATH: 2914 11655
31 208.244.144.128/25 129.250.126.97 4 100 0
EF
AS_PATH: 2914 25626
32 209.69.100.224/28 129.250.126.97 3 100 0
EF
AS_PATH: 2914 18776
33 209.69.154.192/27 129.250.126.97 3 100 0
EF
AS_PATH: 2914 18776
34 210.7.223.0/25 129.250.126.97 3 100 0
EF
AS_PATH: 2914 9874 3549 4682 9335
I think you may be confusing "peer" with "customer".
If you are a customer, you will get other customer routes
as compared to a peer probally doesn't see these.
- Jared
Does anyone (Cisco, Juniper, etc.) have an auto-aggregation feature?
Let's say a router that receives the following prefixes under a single AS
206.51.128.0/24
206.51.129.0/24
206.51.131.0/24
And the following network is not in the table:
206.51.130.0/24
Then it would be usefull to collapse it into a single 206.52.128/22
aggregate (especially if the metrics & communities are the same).
-Ralph