AS197589 - ALFANEWS Alfanews S.r.lPARFC 4890 ✓RPKI ✓ 2/2ASPA -

AS overview

Test target: 2a04:d680::1 · static prefix probe · address space: PA · prefixes announced: 2

prefix(es): 2a04:d680::/32, 2a04:d680::/29

MIX-IT / NAMEX / MINAP / TOP-IX / VSIX / EQUINIX-MILAN / BGPX-ROME / NAMEX-BARI / PCIX / DECIX-PALERMO peering

Random-IP probe (yarrp) into the AS' prefixes

At least one router inside AS197589's announced prefix replied during the random-target probe. Hop(s): 2a04:d680:0:1::2, 2a04:d680:0:4::1. These are candidate targets for direct testing.

ICMPv6 Type 2 (Packet Too Big) acceptance - active test

Type 2 honored. Forged ICMPv6 PTB (MTU=1280) was accepted by the destination's stack: the next 1500-byte Echo Reply arrived split into 2 fragments via the IPv6 Fragment Header.
method: ICMPv6 Echo + forged PTB, tested 2026-09-23T12:04:07Z

Multi-vantage path map

Every hop of all vantages’ traceroutes toward the target, drawn left→right, grouped into per-AS bubbles (a hop seen from several vantages is one shared bubble, so converging paths merge). It answers two questions per vantage — shown on each source bubble as echo ✓/⚠/✗ · trace ✓/✗: did the destination reply to ICMPv6 Echo (✓ honored, ⚠ replied but PTB not honored, ✗ no reply), and did the traceroute reach it. A line to the target is drawn only when that vantage got an echo reply — solid if the PTB was honored, dashed if not (reachable but a broken-PMTUD / RFC 4890 violation). The path depth still shows how far the traceroute itself got, and runs of unanswered (* *) hops collapse into one dashed “silent” bubble. Open full size ↗

• ● SRB host (SOX, Belgrade)
• ● DE host (Berlin)
• ● DE host (Düsseldorf)
• ● NL host (go6lab)
• ● ITA host (Karsolink)
• ● SLO host (6connect)
• ● SLO host (T-2)
• ── solid line = echo reply, PTB honored (clean reach)
• — — dashed line = echo reply but PTB not honored (RFC 4890 violation)
• no line = no echo reply (never reached)
• ◉ target: green = clean, amber = reachable-but-violation / unreachable
• ⚠ suspected drop AS
• ⋯ silent (unanswered) hops
• ● IXP hop

From SRB host (SOX, Belgrade)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.012ms pmtu 1500
 1:  _gateway                                              0.578ms 
 1:  _gateway                                              0.356ms 
 2:  2001:7f8:1e::4                                        0.818ms 
 3:  2001:7f8:30:0:2:1:0:9002                             30.000ms 
 4:  RT.MIX.MIL.IT.retn.net                               24.189ms 
 5:  GW-AlfaNews.retn.net                                 28.852ms 
 6:  2a04:d680:0:5::1                                     37.127ms 
 7:  ipv6.largabanda.it                                   36.081ms reached
     Resume: pmtu 1500 hops 7 back 6 

From DE host (Berlin)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.039ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.675ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.532ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        1.108ms 
 3:  retn.bcix.de                                         10.909ms asymm  5 
 4:  RT.MIX.MIL.IT.retn.net                               27.440ms asymm  5 
 5:  GW-AlfaNews.retn.net                                 19.500ms asymm 11 
 6:  ipv6.largabanda.it                                   27.002ms reached
     Resume: pmtu 1500 hops 6 back 12 

From DE host (Düsseldorf)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.021ms pmtu 1500
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.283ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.262ms 
 2:  eth1-0-12-h5594.edge5-dus1.bb.wiit.network            1.124ms 
 3:  no reply
 4:  lag11.core3-dus1.bb.wiit.network                      0.400ms 
 5:  lag0-vl1011.core1-fra-ix.bb.wiit.network              4.357ms 
 6:  lag0-vl1001.core1-nbg-ncd.bb.wiit.network             7.053ms 
 7:  lag0-vl6.core2-nbg-ncd.bb.wiit.network                6.943ms 
 8:  lag0-vl1006.core2-muc2.bb.wiit.network               15.426ms 
 9:  lag0-vl1009.core1-muc-eq3.bb.wiit.network            10.015ms 
10:  lag0-vl1001.core1-pda-vsix.bb.wiit.network           53.806ms 
11:  lag0-vl1001.core1-mil-mix.bb.wiit.network            20.216ms asymm  9 
12:  alfanews-AS197589-v6.mix-it.net                      20.732ms asymm 10 
13:  ipv6.largabanda.it                                   27.733ms reached
     Resume: pmtu 1500 hops 13 back 11 

From NL host (go6lab)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.037ms pmtu 1500
 1:  2a00:8642:42::2                                       2.301ms 
 1:  2a00:8642:42::2                                       1.682ms 
 2:  gw.friends.steffann.nl                                4.224ms 
 3:  ccr2-ccr1.dc1.nogalliance.org                         2.515ms asymm  2 
 4:  ams-ix.retn.net                                       6.247ms asymm  7 
 5:  RT.MIX.MIL.IT.retn.net                               18.741ms asymm  6 
 6:  GW-AlfaNews.retn.net                                 19.818ms asymm  7 
 7:  ipv6.largabanda.it                                   26.619ms reached
     Resume: pmtu 1500 hops 7 back 8 

From ITA host (Karsolink)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.029ms pmtu 1500
 1:  no reply
 2:  no reply
 3:  no reply
 4:  alfanews-as197589-v6.mix-it.net                       9.215ms 
 5:  ipv6.largabanda.it                                   16.546ms reached
     Resume: pmtu 1500 hops 5 back 5 

From SLO host (6connect)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 4, hop 6 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.018ms pmtu 9000
 1:  fw1-lju.6connect.com                                  0.726ms 
 1:  fw1-lju.6connect.com                                  0.519ms 
 2:  no reply
 3:  2a03:a100:0:201:1::1                                  1.361ms 
 4:  2a03:a100:0:201:1::1                                  0.910ms pmtu 1500
 4:  e0-1.core1.lju1.he.net                                3.372ms 
 5:  no reply
 6:  port-channel1.core1.zag2.he.net                       5.414ms 
 7:  no reply
 8:  alfanews-AS197589-v6.mix-it.net                      10.978ms asymm  7 
 9:  ipv6.largabanda.it                                   18.285ms reached
     Resume: pmtu 1500 hops 9 back 7 

From SLO host (T-2)   openRFC 4890 ✓

filter likely at: (none) · min PMTU on path: 1500

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 6, hop 7 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.031ms pmtu 1500
 1:  no reply
 2:  2a01:260:1::225                                       5.517ms 
 3:  2a01-260-1-1--9a.core6.t-2.net                        3.247ms 
 4:  2a01-260-1-1--39.core6.t-2.net                        2.435ms asymm  3 
 5:  be1.core2.fra2.he.net                                37.419ms 
 6:  be3.core4.fra1.he.net                                49.583ms asymm  7 
 7:  be3.core4.fra1.he.net                                46.164ms 
 8:  be10.core1.zrh2.he.net                               50.051ms 
 9:  be1.core1.mil2.he.net                                36.940ms asymm  7 
10:  alfanews-AS197589-v6.mix-it.net                      36.059ms asymm  7 
11:  2a04:d680:0:5::1                                     40.418ms asymm  8 
12:  2a04:d680:0:5::1                                     43.591ms asymm  8 
13:  ipv6.largabanda.it                                   40.056ms reached
     Resume: pmtu 1500 hops 13 back 8