Observed topology
AS5408 GR-NET www.grnet.gr
Transit
Upstream networks
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.
| AS | Network | Type | Families | Paths seen |
|---|---|---|---|---|
| AS21320 | GEANT Vereniging | Unclassified | IPv4 IPv6 | 1,382 |
| AS13335 | Cloudflare, Inc. | Hosting | IPv4 | 259 |
| AS20965 | GEANT Vereniging | Unclassified | IPv4 IPv6 | 208 |
| AS3491 | PCCW Global (HK) Ltd. | Transit | IPv4 | 76 |
| AS8280 | SYNAPSECOM S.A. Provider of Telecommunications and Internet Services | Hosting | IPv4 IPv6 | 26 |
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
Networks for which AS5408 was observed as the last hop before the origin, meaning it appears to provide them transit.
| AS | Network | Type | Families | Paths seen |
|---|---|---|---|---|
| AS8248 | Computer Technology Institute and Press "Diophantus" | Education | IPv4 IPv6 | 511 |
| AS8762 | Hellenic Mediterranean University | Education | IPv4 IPv6 | 476 |
| AS8581 | University Of Ioannina | Education | IPv4 IPv6 | 476 |
| AS15690 | NATIONAL OBSERVATORY OF ATHENS | Unclassified | IPv4 IPv6 | 287 |
| AS8643 | NATIONAL AND KAPODISTRIAN UNIVERSITY OF ATHENS | Education | IPv4 IPv6 | 287 |
| AS12402 | University of Piraeus | Unclassified | IPv4 IPv6 | 287 |
| AS31563 | Hellenic National Meteorological Service | Unclassified | IPv4 IPv6 | 255 |
| AS8617 | of the Aegean | Education | IPv4 | 252 |
| AS8618 | University | Education | IPv4 | 252 |
| AS8991 | Hellenic Centre for Marine Research | Unclassified | IPv4 | 250 |
| AS8253 | Democritus University of Thrace | Education | IPv4 IPv6 | 224 |
| AS9069 | Athens Egaleo GREECE | Education | IPv4 IPv6 | 222 |
| AS15948 | fundamental and technological research | Unclassified | IPv4 | 189 |
| AS8611 | University of Economics and Business | Education | IPv4 | 189 |
| AS5489 | International Hellenic University | Education | IPv4 | 189 |
| AS6867 | University of Crete | Education | IPv4 IPv6 | 161 |
| AS5470 | Aristotle University of Thessaloniki | Education | IPv4 IPv6 | 161 |
| AS12364 | University of Macedonia, Economic and Social Sciences | Unclassified | IPv4 IPv6 | 161 |
| AS8522 | Foundation of Research and Technology Hellas | Education | IPv4 IPv6 | 161 |
| AS20813 | Hellenic Open University | Unclassified | IPv4 | 126 |
| AS202640 | KENTRO POLITISMOU IDRYMA STAVROS NIARCHOS MONOPROSOPI A.E. | Unclassified | IPv4 IPv6 | 99 |
| AS8278 | Technical University of Crete | Education | IPv4 IPv6 | 98 |
| AS3323 | National Technical University of Athens | Education | IPv4 IPv6 | 98 |
| AS2546 | National Center of Scientific Research DEMOKRITOS | Education | IPv4 IPv6 | 98 |
| AS47616 | Center for Research and Technology Hellas (CERTH) | Unclassified | IPv4 IPv6 | 98 |
| AS203348 | Hellenic Telecommunications and Post Commision | Unclassified | IPv4 IPv6 | 70 |
| AS50148 | Elliniki Radiofonia Tileorasi (ERT) SA | Unclassified | IPv4 | 65 |
| AS6744 | Computer Technology Institute and Press "Diophantus" | Education | IPv4 | 63 |
| AS15536 | European Centre for the Development of Vocational Training (CEDEFOP) | Unclassified | IPv4 | 57 |
| AS47065 | USC / UFMG PEERING Research Testbed | Education | IPv4 IPv6 | 37 |
Adjacency
Adjacent networks
Every AS seen directly next to AS5408 in a routing path, in either direction.
| AS | Network | Type | Families | Paths seen |
|---|---|---|---|---|
| AS21320 | GEANT Vereniging | Unclassified | IPv4 IPv6 | 6,776 |
| AS20965 | GEANT Vereniging | Unclassified | IPv4 IPv6 | 672 |
| AS8248 | Computer Technology Institute and Press "Diophantus" | Education | IPv4 IPv6 | 511 |
| AS8581 | University Of Ioannina | Education | IPv4 IPv6 | 476 |
| AS8762 | Hellenic Mediterranean University | Education | IPv4 IPv6 | 476 |
| AS8522 | Foundation of Research and Technology Hellas | Education | IPv4 IPv6 | 383 |
| AS3491 | PCCW Global (HK) Ltd. | Transit | IPv4 IPv6 | 329 |
| AS8643 | NATIONAL AND KAPODISTRIAN UNIVERSITY OF ATHENS | Education | IPv4 IPv6 | 287 |
| AS15690 | NATIONAL OBSERVATORY OF ATHENS | Unclassified | IPv4 IPv6 | 287 |
| AS12402 | University of Piraeus | Unclassified | IPv4 IPv6 | 287 |
| AS13335 | Cloudflare, Inc. | Hosting | IPv4 | 259 |
| AS31563 | Hellenic National Meteorological Service | Unclassified | IPv4 IPv6 | 255 |
| AS8617 | of the Aegean | Education | IPv4 | 252 |
| AS8618 | University | Education | IPv4 | 252 |
| AS8991 | Hellenic Centre for Marine Research | Unclassified | IPv4 | 250 |
| AS8253 | Democritus University of Thrace | Education | IPv4 IPv6 | 224 |
| AS9069 | Athens Egaleo GREECE | Education | IPv4 IPv6 | 222 |
| AS5489 | International Hellenic University | Education | IPv4 | 189 |
| AS15948 | fundamental and technological research | Unclassified | IPv4 | 189 |
| AS8611 | University of Economics and Business | Education | IPv4 | 189 |
| AS5470 | Aristotle University of Thessaloniki | Education | IPv4 IPv6 | 161 |
| AS12364 | University of Macedonia, Economic and Social Sciences | Unclassified | IPv4 IPv6 | 161 |
| AS6867 | University of Crete | Education | IPv4 IPv6 | 161 |
| AS47065 | USC / UFMG PEERING Research Testbed | Education | IPv4 IPv6 | 139 |
| AS8280 | SYNAPSECOM S.A. Provider of Telecommunications and Internet Services | Hosting | IPv4 IPv6 | 138 |
| AS20813 | Hellenic Open University | Unclassified | IPv4 | 126 |
| AS202640 | KENTRO POLITISMOU IDRYMA STAVROS NIARCHOS MONOPROSOPI A.E. | Unclassified | IPv4 IPv6 | 99 |
| AS3323 | National Technical University of Athens | Education | IPv4 IPv6 | 98 |
| AS8278 | Technical University of Crete | Education | IPv4 IPv6 | 98 |
| AS2546 | National Center of Scientific Research DEMOKRITOS | Education | IPv4 IPv6 | 98 |
| AS47616 | Center for Research and Technology Hellas (CERTH) | Unclassified | IPv4 IPv6 | 98 |
| AS203348 | Hellenic Telecommunications and Post Commision | Unclassified | IPv4 IPv6 | 70 |
| AS50148 | Elliniki Radiofonia Tileorasi (ERT) SA | Unclassified | IPv4 | 65 |
| AS6744 | Computer Technology Institute and Press "Diophantus" | Education | IPv4 | 63 |
| AS15536 | European Centre for the Development of Vocational Training (CEDEFOP) | Unclassified | IPv4 | 57 |
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
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.
| Exchange | Location | Their address | Member ports |
|---|---|---|---|
| Greek Internet Exchange - Athens | Athens, Greece | 176.126.38.1 | 75 |
| Greek Internet Exchange - Thessaloniki | Thessaloniki, Greece | 185.1.123.20 | 22 |
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.