asn.dev

Observed topology

AS5408 GR-NET www.grnet.gr

Upstreams 5 carry this network
Downstreams 30 this network carries
Adjacent (IPv4) 35
Adjacent (IPv6) 24

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS5408: the AS immediately before it in a routing path. Ranked by how many paths showed the relationship, which reflects how widely it is used, not how much traffic crosses it.

ASNetworkTypeFamiliesPaths seen
AS21320GEANT VerenigingUnclassifiedIPv4 IPv61,382
AS13335Cloudflare, Inc.HostingIPv4259
AS20965GEANT VerenigingUnclassifiedIPv4 IPv6208
AS3491PCCW Global (HK) Ltd.TransitIPv476
AS8280SYNAPSECOM S.A. Provider of Telecommunications and Internet ServicesHostingIPv4 IPv626

Inferred from path position, not from any declaration by either party. A network appearing here is carrying these routes; whether that is a paid transit arrangement, a backup, or something else is not something routing data can tell you.

Transit

Downstream networks

inferred

Networks for which AS5408 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS8248Computer Technology Institute and Press "Diophantus"EducationIPv4 IPv6511
AS8762Hellenic Mediterranean UniversityEducationIPv4 IPv6476
AS8581University Of IoanninaEducationIPv4 IPv6476
AS15690NATIONAL OBSERVATORY OF ATHENSUnclassifiedIPv4 IPv6287
AS8643NATIONAL AND KAPODISTRIAN UNIVERSITY OF ATHENSEducationIPv4 IPv6287
AS12402University of PiraeusUnclassifiedIPv4 IPv6287
AS31563Hellenic National Meteorological ServiceUnclassifiedIPv4 IPv6255
AS8617of the AegeanEducationIPv4252
AS8618UniversityEducationIPv4252
AS8991Hellenic Centre for Marine ResearchUnclassifiedIPv4250
AS8253Democritus University of ThraceEducationIPv4 IPv6224
AS9069Athens Egaleo GREECEEducationIPv4 IPv6222
AS15948fundamental and technological researchUnclassifiedIPv4189
AS8611University of Economics and BusinessEducationIPv4189
AS5489International Hellenic UniversityEducationIPv4189
AS6867University of CreteEducationIPv4 IPv6161
AS5470Aristotle University of ThessalonikiEducationIPv4 IPv6161
AS12364University of Macedonia, Economic and Social SciencesUnclassifiedIPv4 IPv6161
AS8522Foundation of Research and Technology HellasEducationIPv4 IPv6161
AS20813Hellenic Open UniversityUnclassifiedIPv4126
AS202640KENTRO POLITISMOU IDRYMA STAVROS NIARCHOS MONOPROSOPI A.E.UnclassifiedIPv4 IPv699
AS8278Technical University of CreteEducationIPv4 IPv698
AS3323National Technical University of AthensEducationIPv4 IPv698
AS2546National Center of Scientific Research DEMOKRITOSEducationIPv4 IPv698
AS47616Center for Research and Technology Hellas (CERTH)UnclassifiedIPv4 IPv698
AS203348Hellenic Telecommunications and Post CommisionUnclassifiedIPv4 IPv670
AS50148Elliniki Radiofonia Tileorasi (ERT) SAUnclassifiedIPv465
AS6744Computer Technology Institute and Press "Diophantus"EducationIPv463
AS15536European Centre for the Development of Vocational Training (CEDEFOP)UnclassifiedIPv457
AS47065USC / UFMG PEERING Research TestbedEducationIPv4 IPv637

Adjacency

Adjacent networks

59 shown

Every AS seen directly next to AS5408 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS21320GEANT VerenigingUnclassifiedIPv4 IPv66,776
AS20965GEANT VerenigingUnclassifiedIPv4 IPv6672
AS8248Computer Technology Institute and Press "Diophantus"EducationIPv4 IPv6511
AS8581University Of IoanninaEducationIPv4 IPv6476
AS8762Hellenic Mediterranean UniversityEducationIPv4 IPv6476
AS8522Foundation of Research and Technology HellasEducationIPv4 IPv6383
AS3491PCCW Global (HK) Ltd.TransitIPv4 IPv6329
AS8643NATIONAL AND KAPODISTRIAN UNIVERSITY OF ATHENSEducationIPv4 IPv6287
AS15690NATIONAL OBSERVATORY OF ATHENSUnclassifiedIPv4 IPv6287
AS12402University of PiraeusUnclassifiedIPv4 IPv6287
AS13335Cloudflare, Inc.HostingIPv4259
AS31563Hellenic National Meteorological ServiceUnclassifiedIPv4 IPv6255
AS8617of the AegeanEducationIPv4252
AS8618UniversityEducationIPv4252
AS8991Hellenic Centre for Marine ResearchUnclassifiedIPv4250
AS8253Democritus University of ThraceEducationIPv4 IPv6224
AS9069Athens Egaleo GREECEEducationIPv4 IPv6222
AS5489International Hellenic UniversityEducationIPv4189
AS15948fundamental and technological researchUnclassifiedIPv4189
AS8611University of Economics and BusinessEducationIPv4189
AS5470Aristotle University of ThessalonikiEducationIPv4 IPv6161
AS12364University of Macedonia, Economic and Social SciencesUnclassifiedIPv4 IPv6161
AS6867University of CreteEducationIPv4 IPv6161
AS47065USC / UFMG PEERING Research TestbedEducationIPv4 IPv6139
AS8280SYNAPSECOM S.A. Provider of Telecommunications and Internet ServicesHostingIPv4 IPv6138
AS20813Hellenic Open UniversityUnclassifiedIPv4126
AS202640KENTRO POLITISMOU IDRYMA STAVROS NIARCHOS MONOPROSOPI A.E.UnclassifiedIPv4 IPv699
AS3323National Technical University of AthensEducationIPv4 IPv698
AS8278Technical University of CreteEducationIPv4 IPv698
AS2546National Center of Scientific Research DEMOKRITOSEducationIPv4 IPv698
AS47616Center for Research and Technology Hellas (CERTH)UnclassifiedIPv4 IPv698
AS203348Hellenic Telecommunications and Post CommisionUnclassifiedIPv4 IPv670
AS50148Elliniki Radiofonia Tileorasi (ERT) SAUnclassifiedIPv465
AS6744Computer Technology Institute and Press "Diophantus"EducationIPv463
AS15536European Centre for the Development of Vocational Training (CEDEFOP)UnclassifiedIPv457

Adjacency is not the same as peering. Being next to each other in a path covers paid transit, settlement-free peering and customer connections alike, and routing data cannot distinguish them. Treat this as "these networks exchange routes", nothing more specific.

Interconnection

Exchange presence

recorded

Internet exchanges where Packet Clearing House has a port recorded for AS5408, largest fabric first. An exchange is shared switching where networks interconnect directly rather than paying a transit provider to carry traffic between them, so turning up at one is a deliberate choice about how this network wants to be reached. Each name opens that exchange's own page, with its peering LANs and every other network recorded on it. Recorded at 2 exchanges across 1 country and 1 region.

ExchangeLocationTheir addressMember ports
Greek Internet Exchange - AthensAthens, Greece176.126.38.175
Greek Internet Exchange - ThessalonikiThessaloniki, Greece185.1.123.2022

Unlike the tables above, this is recorded rather than inferred. An address on a peering LAN is at that exchange by definition. Two carve-outs all the same. Member ports counts every participant at the exchange, not this network's ports, so read it as a size proxy. And an absent exchange means PCH has no record of it, not that the network is not there.

Provenance

Where this comes from

Derived from routing tables collected at 2026-08-08 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 74.02M route entries. These are observations from those vantage points, not a complete or authoritative view of the internet.

Cross-check against RIPEstat or BGP.tools, which observe from a different and larger set of vantage points.

Exchange presence comes from a separate dataset: the directory collected 2026-08-08 by Packet Clearing House (https://www.pch.net/ixp/data), covering 1,327 exchanges and 93,137 recorded member ports, licensed CC BY-NC-SA 3.0.

PeeringDB is the better-known directory and is deliberately not the source here: its acceptable-use policy forbids the bulk storage this needs. The two answer different questions anyway. PeeringDB reports what an operator declares about itself; this reports what PCH has recorded.