The CESNET NIC authority allocates address resources (IP addresses) to entities connected to the CESNET3 network, ensures communication with Réseaux IP Européens Network Coordination Centre (RIPE NCC) and maintains contact information on allocated networks in the RIPE database up to data.

Each range of internet resource (IP addresses) is directly allocated to a particular entity to which it has been allocated. The contact information of the entity is saved in a publicly available database administered by RIPE NCC. The CESNET NIC authority monitors the changes by RIPE NCC and manages the address ranges of the participants accordingly. The participant’s cooperation is vital for this task.

The participants of the CESNET e-infrastructure are obliged to communicate and cooperate with the CESNET NIC authority, in particular as regards maintaining contact information on allocated resources up to date.

The entity is obliged to return the allocated address resource upon the termination of the contractual relations and disconnection from the CESNET3 network.

Entities connected or in the process of connecting can request the following from CESNET NIC:

  • Allocation of first address range (both IPv4 and IPv6);
  • Allocation of next address range (in case of depleted current address range not allowing extending the connected institution network);
  • Change of contact information in the RIPE database.


In addition, CESNET provides the following services (subject to charges):

  • LIR sponsoring;
  • Assistance in establishing own LIR authority;
  • Assistance in launching IPv6 protocol.

Key benefits

  • Comprehensive administration of Internet resources in a single spot.

Target audience

The service is available to entities connected to the CESNET e-infrastructure, and entities in the process of being connected to the CESNET e-infrastructure.


The basic CESNET NIC service is provided to the participants free of charge.

As regards LIR sponsoring, assistance in establishing own LIR and assistance in launching the network IPv6 protocol, the fee is determined individually.


All relevant information, forms and guidelines can be found at the CESNET NIC website.

Related services

Last change: 8.11.2023