AS5392 - TELNET-ITALY TELNET S.r.lPARFC 4890 ✓RPKI ✓ 1/1ASPA -

AS overview

Test target: 2a00:1988::c324:168 · telnet.it · address space: PA · prefixes announced: 1

prefix(es): 2a00:1988::/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

We probed 35 arbitrary IPv6 address(es) inside AS5392's announced prefix(es). No router inside the prefix responded. The deepest visible hop was 2a11:4141:5002::11 at hop 15 - that router answers ICMPv6 Echo. This is not in AS5392's announced prefix; operationally it's the AS-edge / peering interface (often on an IXP peering address or an upstream's /127 link). The traceroute boundary is the AS edge: ICMPv6 Time-Exceeded responses from anything inside this AS are filtered.

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 2026-09-23T12:00:29Z

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 8, hop 9 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.018ms pmtu 1500
 1:  _gateway                                              0.537ms 
 1:  _gateway                                              0.758ms 
 2:  sox-pn.sox.rs                                         0.462ms 
 3:  2001:7f8:1e:8::3d                                     0.664ms asymm  2 
 4:  2001:67c:128c::699                                   20.015ms 
 5:  hu0-15-0-0.lontr4.London.opentransit.net             41.837ms asymm  6 
 6:  no reply
 7:  be4.core2.ams2.he.net                                42.371ms 
 8:  be1.core2.fra2.he.net                                41.291ms asymm  6 
 9:  be3.core4.fra1.he.net                                43.155ms asymm  7 
10:  be10.core1.zrh2.he.net                               45.742ms asymm  8 
11:  be1.core1.mil2.he.net                                44.900ms asymm  7 
12:  no reply
13:  telnet.minap.it                                      43.590ms asymm  7 
14:  itaca.telnetwork.it                                  43.689ms reached
     Resume: pmtu 1500 hops 14 back 8 

From DE host (Berlin)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.029ms pmtu 1500
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.900ms 
 1:  xe-0-0-13-178.gw01.ber01.as59645.net                  0.707ms 
 2:  ae0-2453.cr10.ber01.lwlcom.net                        1.258ms 
 3:  ae0-10.cr10.ber03.lwlcom.net                          1.238ms 
 4:  ae0-15.cr11.dtm01.lwlcom.net                          8.837ms asymm  5 
 5:  ae0-10.cr10.dtm02.lwlcom.net                          9.072ms asymm  6 
 6:  ae0-20.cr10.dus04.lwlcom.net                         10.133ms asymm  5 
 7:  ae0-20.cr10.dus01.lwlcom.net                          8.983ms asymm  4 
 8:  ae6-60.cr10.ams01.lwlcom.net                         11.744ms asymm  5 
 9:  as5405.frys-ix.net                                   11.707ms 
10:  r7-ams1-nl.as5405.net                                26.031ms asymm 13 
11:  r7-fra1-de.as5405.net                                26.021ms asymm 12 
12:  r3-fra1-de.as5405.net                                26.087ms asymm 11 
13:  r2-zrh1-ch.as5405.net                                25.973ms asymm 10 
14:  r1-mil1-it.as5405.net                                25.972ms asymm  9 
15:  2a11:4141:5002::11                                   26.016ms asymm 11 
16:  telnet.minap.it                                      26.012ms asymm 10 
17:  itaca.telnetwork.it                                  26.083ms reached
     Resume: pmtu 1500 hops 17 back 11 

From DE host (Düsseldorf)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

tracepath -6

 1?: [LOCALHOST]                        0.013ms pmtu 1500
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.467ms 
 1:  xe-0-0-12-142.gw01.dus01.as59645.net                  0.210ms 
 2:  eth1-0-12-h5594.edge5-dus1.bb.wiit.network           21.677ms 
 3:  no reply
 4:  lag30.core3-dus1.bb.wiit.network                      0.403ms 
 5:  lag0-vl1011.core1-fra-ix.bb.wiit.network              4.271ms 
 6:  lag0-vl1001.core1-nbg-ncd.bb.wiit.network             6.738ms 
 7:  lag0-vl6.core2-nbg-ncd.bb.wiit.network                6.759ms 
 8:  lag0-vl1006.core2-muc2.bb.wiit.network                9.471ms 
 9:  lag0-vl1009.core1-muc-eq3.bb.wiit.network             9.726ms 
10:  lag0-vl1001.core1-pda-vsix.bb.wiit.network           20.527ms 
11:  lag0-vl1001.core1-mil-mix.bb.wiit.network            20.382ms asymm  9 
12:  lag0-vl5.core3-mil-irid.bb.wiit.network              20.112ms asymm  8 
13:  telnet2.minap.it                                     20.042ms asymm  9 
14:  itaca.telnetwork.it                                  20.329ms reached
     Resume: pmtu 1500 hops 14 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 3, hop 4 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.036ms pmtu 1500
 1:  2a00:8642:42::2                                       2.380ms 
 1:  2a00:8642:42::2                                       4.594ms 
 2:  gw.friends.steffann.nl                                4.294ms 
 3:  speed-ix.he.net                                      16.839ms 
 4:  be2.core4.fra1.he.net                                18.312ms 
 5:  be10.core1.zrh2.he.net                               23.181ms 
 6:  be1.core1.mil2.he.net                                23.736ms 
 7:  no reply
 8:  telnet.minap.it                                      22.722ms 
 9:  itaca.telnetwork.it                                  19.142ms 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)

tracepath -6

 1?: [LOCALHOST]                        0.069ms pmtu 1500
 1:  karsolink-01.net.karsolink.com                        1.572ms 
 2:  2a12:d8c0:109f:121::a1                                1.524ms 
 3:  2a12:d8c0:101f:6::1                                  10.218ms 
 4:  telnet.minap.it                                      10.652ms asymm  6 
 5:  itaca.telnetwork.it                                  10.886ms reached
     Resume: pmtu 1500 hops 5 back 7 

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, hop 8 (loss between 5% and 95% across mtr cycles - the router replies but only sometimes).

tracepath -6

 1?: [LOCALHOST]                        0.027ms pmtu 9000
 1:  fw1-lju.6connect.com                                  1.251ms 
 1:  fw1-lju.6connect.com                                  0.709ms 
 2:  no reply
 3:  2a03:a100:0:201:1::1                                  0.909ms 
 4:  2a03:a100:0:201:1::1                                  1.059ms pmtu 1500
 4:  e0-1.core1.lju1.he.net                                2.267ms 
 5:  no reply
 6:  port-channel1.core1.zag2.he.net                       4.223ms 
 7:  no reply
 8:  telnet2.minap.it                                     12.634ms 
 9:  itaca.telnetwork.it                                  12.540ms reached
     Resume: pmtu 1500 hops 9 back 9 

From SLO host (T-2)   openRFC 4890 ✓

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

Path (traceroute + mtr + PTR)

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

tracepath -6

 1?: [LOCALHOST]                        0.035ms pmtu 1500
 1:  2a01:261:313:b814::1                                  2.750ms 
 1:  2a01:261:313:b814::1                                  0.885ms 
 2:  2a01:260:1::225                                       4.710ms 
 3:  2a01-260-1-1--9a.core6.t-2.net                        2.202ms 
 4:  2a01-260-1-1--38.core6.t-2.net                        2.717ms asymm  3 
 5:  port-channel1.core1.zag2.he.net                      10.376ms asymm  7 
 6:  port-channel1.core1.zag2.he.net                       9.946ms asymm  7 
 7:  telnet2.minap.it                                     17.060ms 
 8:  itaca.telnetwork.it                                  16.337ms reached
     Resume: pmtu 1500 hops 8 back 8