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Autonomous System details for AS203208

AS203208
Czech Telecommunication Office • ctu.cz

AS203208 — Czech Telecommunication Office

AS Name
CTU_AS4_2
Country
Czechia (CZ)
Website
Number of IPv4
768
Number of IPv6
5.55 × 1029
ASN type
ISP
Status
Allocated
Registry
RIPE
Allocated
March 08, 2016
Last updated
July 04, 2025

IP Ranges

2 IPv4 prefixes, 3 IPv6 prefixes
Prefix Company Number of IPs
185.68.212.0/23 Czech Telecommunication Office 512
185.68.214.0/24 Czech Telecommunication Office 256
2a05:1c40::/30 Czech Telecommunication Office 3.17 × 1029
2a05:1c44::/31 CTU SOKOLOVSKA 1.58 × 1029
2a05:1c46::/32 CTU SOKOLOVSKA 7.92 × 1028

IP ranges are the different blocks of IP addresses advertised by an Autonomous System (AS). These ranges can be used by the same organization operating the AS, or by different organizations.

Peers of AS203208

0 peers

AS203208 has no peers recorded.

Peering is a direct, often free, traffic exchange between Autonomous Systems (ASNs). They share routes only to their own networks and customers, making connections faster and cheaper for that specific traffic, without providing full internet access to each other.

Upstreams of AS203208

1 upstreams

AS203208 uses these Autonomous Systems as its upstreams.

An upstream (or transit provider) is another AS that AS203208 pays for full internet connectivity, allowing it to reach all global destinations and be reachable by them.

Downstreams of AS203208

0 downstreams

AS203208 has no downstreams recorded.

A downstream is a customer Autonomous System that pays another AS (its provider) for internet access. The provider AS carries the downstream's traffic and makes its network reachable.

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