AS203672 - TELEFONICASERVIZI Telefonica Servizi srlPARFC 4890 ✓RPKI -ASPA -

AS overview

Test target: 2a03:9e20::1 · static prefix probe · address space: PA · prefixes announced: 1

prefix(es): 2a03:9e20::/32

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 AS203672's announced prefix replied during the random-target probe. Hop(s): 2a03:9e20:0:2:2::2. 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 2026-09-23T12:03:35Z

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)

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

tracepath -6

 1?: [LOCALHOST]                        0.012ms pmtu 1500
 1:  _gateway                                              0.726ms 
 1:  _gateway                                              0.389ms 
 2:  sox-pn.sox.rs                                         0.541ms 
 3:  2001:7f8:1e:8::3d                                     1.043ms asymm  2 
 4:  ae8-930.RT.IRX.VIE.AT.retn.net                       12.973ms asymm  3 
 5:  RT.MIX.MIL.IT.retn.net                               24.280ms asymm  4 
 6:  fastweb-v6.mix-it.net                                30.055ms asymm  5 
 7:  2001:b00:1:1:3::135                                  29.169ms asymm  6 
 8:  2001:b00:1:1:1::181                                  38.366ms asymm  7 
 9:  2001:b00:1:1:4::cb                                   41.611ms asymm  8 
10:  gw1.telefonicaservizi.it                             39.663ms reached
     Resume: pmtu 1500 hops 10 back 9 

From DE host (Berlin)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

Rate-limited ICMPv6: hop 15, hop 18 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.035ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.430ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.455ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        0.986ms 
 3:  ae0-10.cr10.ber03.lwlcom.net                          1.190ms 
 4:  ae0-15.cr11.dtm01.lwlcom.net                          8.725ms asymm  5 
 5:  ae0-10.cr10.dtm02.lwlcom.net                         17.928ms asymm  6 
 6:  ae0-20.cr10.dus04.lwlcom.net                          8.823ms asymm  5 
 7:  ae0-10.cr10.dus01.lwlcom.net                          8.701ms asymm  4 
 8:  ae0-90.cr11.dus01.lwlcom.net                          9.500ms asymm  5 
 9:  as3303.dusseldorf.megaport.com                       17.716ms asymm 13 
10:  i00ffm-005-loo179.bb.ip-plus.net                     17.874ms asymm 12 
11:  i62bsw-015-loo179.ip6.ip-plus.net                    17.998ms asymm 14 
12:  i73olt-005-loo179.bb.ip-plus.net                     17.716ms 
13:  i71lzf-015-loo179.bb.ip-plus.net                     18.372ms asymm 12 
14:  i63bel-005-loo179.bb.ip-plus.net                     20.166ms asymm 13 
15:  as3303-as12874-bel-001-ser0.ce.ip-plus.net           22.266ms asymm  9 
16:  2001:b00:1:1:1::1a9                                  23.057ms asymm  8 
17:  2001:b00:1:1:1::17d                                  33.605ms asymm  9 
18:  2001:b00:1:1:4::cb                                   36.870ms asymm 10 
19:  gw1.telefonicaservizi.it                             35.218ms reached
     Resume: pmtu 1500 hops 19 back 11 

From DE host (Düsseldorf)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.022ms pmtu 1500
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.366ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.326ms 
 2:  eth1-0-12-h5594.edge5-dus1.bb.wiit.network            1.284ms 
 3:  no reply
 4:  lag30.core3-dus1.bb.wiit.network                      0.506ms 
 5:  lag8.core1-dus-ix.bb.wiit.network                     0.579ms 
 6:  no reply
 7:  2001:b00:1:1:1::1ad                                  17.308ms 
 8:  2001:b00:1:1:1::17d                                  28.678ms 
 9:  2001:b00:1:1:4::cb                                   27.992ms 
10:  gw1.telefonicaservizi.it                             29.419ms reached
     Resume: pmtu 1500 hops 10 back 10 

From NL host (go6lab)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.046ms pmtu 1500
 1:  2a00:8642:42::2                                       3.117ms 
 1:  2a00:8642:42::2                                       3.848ms 
 2:  no reply
 3:  2a00:1ca8:1::194                                      5.536ms 
 4:  2a03:3f40::10:33                                      8.085ms 
 5:  no reply
 6:  2001:b00:1:1:3::139                                  23.197ms 
 7:  2001:b00:1:1:1::181                                  40.782ms 
 8:  2001:b00:1:1:4::cd                                   32.095ms 
 9:  gw1.telefonicaservizi.it                             35.164ms reached
     Resume: pmtu 1500 hops 9 back 9 

From ITA host (Karsolink)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.032ms pmtu 1500
 1:  karsolink-01.net.karsolink.com                        0.821ms 
 1:  no reply
 2:  2a12:d8c0:109f:121::a1                                0.659ms 
 3:  2a12:d8c0:109f:106::a2                                3.636ms 
 4:  2001:7f8:5f:ffff::3                                   9.354ms 
 5:  2001:b00:1:1:3::137                                   8.497ms 
 6:  2001:b00:1:1:1::181                                  21.539ms 
 7:  2001:b00:1:1:4::cb                                   19.646ms 
 8:  gw1.telefonicaservizi.it                             20.013ms reached
     Resume: pmtu 1500 hops 8 back 8 

From SLO host (6connect)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.044ms pmtu 9000
 1:  fw1-lju.6connect.com                                  0.522ms 
 1:  fw1-lju.6connect.com                                  0.508ms 
 2:  no reply
 3:  2a03:a100:0:201:1::1                                  1.121ms 
 4:  2a03:a100:0:201:1::1                                  0.895ms pmtu 1500
 4:  2001:7f8:46:0:1::3303                                 7.900ms asymm  5 
 5:  i00mil-005-loo179.bb.ip-plus.net                      8.132ms asymm  6 
 6:  2001:4d98:a000::119                                  25.602ms asymm 10 
 7:  2001:b00:1:1:1::1ad                                  10.381ms asymm  9 
 8:  2001:b00:1:1:1::17d                                  19.663ms asymm 10 
 9:  2001:b00:1:1:4::cd                                   19.377ms asymm 11 
10:  gw1.telefonicaservizi.it                             25.400ms reached
     Resume: pmtu 1500 hops 10 back 12 

From SLO host (T-2)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.036ms pmtu 1500
 1:  no reply
 2:  2a01:260:1::225                                       4.100ms 
 3:  2a01-260-1-1--9c.core6.t-2.net                        2.884ms 
 4:  2001:7f8:46:0:1::3303                                10.496ms 
 5:  i00mil-005-loo179.bb.ip-plus.net                      9.757ms 
 6:  2001:4d98:a000::119                                  25.753ms asymm 11 
 7:  2001:b00:1:1:3::13b                                  15.481ms asymm  8 
 8:  2001:b00:1:1:1::17d                                  23.319ms asymm  9 
 9:  2001:b00:1:1:4::cb                                   24.878ms asymm 10 
10:  gw1.telefonicaservizi.it                             28.753ms reached
     Resume: pmtu 1500 hops 10 back 11