IP Address

IOP Publishing authenticates institutional subscribers by their registered Internet Protocol (IP) addresses. IOP Publishing only accepts IP ranges that belong to the subscribing institution or that the institution uses exclusively.  All institutional subscribers must provide their IP addresses or IP ranges within the licence agreement. Library administrators may submit updates or corrections directly through TheIPRegistry.

To ensure the accuracy of usage reporting, IOP Publishing does not permit IP address sharing across multiple institutions or accounts. When an IP address conflicts with one already registered in our system, our Customer Services team contacts both institutions to resolve the issue. Users must not systematically or automatically download content through authorised IP ranges.

All submitted IP addresses are subject to review and approval. We reserve the right to reject any IP ranges that do not meet these criteria. For accurate information, please consult your network administrator.

For a clearer explanation of how IP addresses work and why they matter for access, take a look at our ‘IP Address Glossary’ article. It breaks down the key terms and concepts so you can understand exactly what’s happening behind the scenes.

Should you need assistance, please refer to IPRegistry’s FAQs or contact the IP Registry team. If the issue relates to your IOPscience access, our Customer Services team is also here to help.

If you have any further questions, please contact our Customer Service team.

IP (Internet Protocol):

What it is: A set of rules that allows devices to send data to each other across a network or the internet.
Why it matters: Every device needs an IP address so it can be identified and reached, much like a postal address for digital communication.
How it works: Data is broken into packets, labelled with source and destination IP addresses, and routed across networks until it reaches the right device.

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IPv4 (Internet Protocol version 4):

What it is: The fourth version of the Internet Protocol and the most widely used addressing system on the internet.
Address format: Four numbers separated by dots, for example: 192.168.1.10.
Capacity: About 4.3 billion unique addresses.
Why it matters: IPv4 has been the backbone of the internet for decades, but the number of available addresses is limited, which led to the development of IPv6.

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IPv6 (Internet Protocol version 6):

What it is: The newer version of the Internet Protocol designed to replace IPv4.
Address format: Eight groups of hexadecimal numbers separated by colons, for example: 2001:0db8:85a3:0000:0000:8a2e:0370:7334.
Capacity: Effectively unlimited—enough to give every device on Earth (and many more) a unique address.
Why it matters: Supports the growth of the internet, improves routing efficiency, and includes built-in security features like mandatory support for IPsec.

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CIDR (Classless Inter‑Domain Routing):

What it is: A method for defining IP address ranges more efficiently than the old “class‑based” system.
How it works: An IP address is followed by a slash and a number that indicates how many bits of the address define the network. Example: 192.168.1.0/24.
Why it matters: CIDR helps reduce wasted IP space, improves routing, and is essential for modern network design and firewall rules.

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Subnet (Subnetworks):

What it is: A smaller, logical section of a larger network.
Why it matters: Subnets help organise networks, improve performance, and control access by grouping devices.
Example: A company might split its network into subnets for staff, guests, and servers.

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IP Address Range:

What it is: A block of IP addresses defined using CIDR notation.
Why it matters: Commonly used for firewall rules, access control lists, and routing decisions.
Example: 10.0.0.0/16 represents 65,536 IPv4 addresses.

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Public vs Private IP Addresses:

Public IP: Routable on the internet and globally unique.
Private IP: Used inside local networks and not reachable from the internet.
Why it matters: Private IPs conserve public address space and improve security.

If you have any further questions, please contact our Customer Service team.

To ensure secure and reliable access, we require customers to provide valid IPv4 address ranges when requesting IP based authentication. This page explains the types of IP addresses we accept, which ones we cannot accept, and how to check the IP address your organisation is using.

Accepted IP Address Types:

✔️ IPv4 Addresses

We currently support IPv4 addresses in standard format

• IPv4 addresses ‘Single’ – Example: 203.000.113.010
• IPv4 address ‘Range’ – Example: 204.025.040.010 – 204.025.040.123

These addresses must be publicly routable on the internet.

IP Address Types We Cannot Accept:

❌ IPv6 Addresses

We do not currently accept IPv6 addresses or IPv6 ranges.
IPv6 addresses typically look like this: 2001:0db8:85a3::8a2e:0370:7334.

❌ Private IPv4 Addresses

Private IP addresses are used only within internal networks (e.g., office LANs, home networks). They are not routable on the public internet, so they cannot be used for authentication.

Common private IP ranges include:

010.000.000.000 – 010.255.255.255

172.016.000.000 – 172.031.255.255

192.168.000.000 – 192.168.255.255

If your IP address falls within any of these ranges, you will need to provide your organisation’s public IP address instead. This can be obtained from your institutions network administrator.

How to Check Your Current IP Address:

If you are unsure of the IP address your organisation is using, you can check it by visiting:

👉 https://iopscience.iop.org/checkup

This page will display the public IP address seen by our systems.
If you are part of a larger institution, this may be the IP address assigned by your network administrator rather than your individual device.

For a clearer explanation of how IP addresses work and why they matter for access, take a look at our ‘IP Address Glossary’ article. It breaks down the key terms and concepts so you can understand exactly what’s happening behind the scenes.

If you have any further questions, please contact our Customer Service team.

Yes. Many institutions choose to route remote-user access through a proxy server. While this approach is common, proxy technologies vary significantly in how they are set up and maintained. Because of this, we are unable to provide formal support for proxy servers and cannot guarantee every proxy setup will work smoothly with our systems. If you experience access issues, please contact your proxy vendor’s support team for assistance.

Proxy IP Address Registration:

If your institution uses a proxy service, please share the proxy IP address(es) to the support team at TheIPRegistry. Once received, they will authenticate the IP information to enable access to your subscribed content.

Please note:

• Only IP addresses registered solely to your institution can be added.
• Shared or publicly used IP addresses cannot be registered.

If you have any further questions, please contact our Customer Service team.

Introduction

An IP address (Internet Protocol address) is a unique numerical identifier that identifies every device connected to the internet. It works much like a digital home address, helping online services send information to the correct place.

What an IP Address Does

IP addresses perform two key functions:

• Identify your device on a network
• Provide its network location so data can be delivered correctly

Without an IP address, a device cannot communicate online.

Types of IP Addresses

There are two main formats:

• IPv4 — the original and most widely used format (e.g., 192.0.2.1)
• IPv6 — a newer format designed to support a larger number of devices

For access to our services, we only accept IPv4 addresses.
IPv6 addresses cannot be registered or used for authentication.

You may also encounter:

• Public IP addresses — visible to the internet
• Private IP addresses — used within your home or institutional network

How to Locate Your IP Address

To check the IP address your institution is currently using to access our platform, visit:

https://iopscience.iop.org/checkup

This page automatically displays the IP address detected by our system.

Why IP Addresses Matter for Access

Many institutions use IP authentication to provide seamless access to subscribed online content. When your public IPv4 address matches an approved institutional range, access is granted automatically.

If your institution needs to register or update its IP addresses, your administrator may be asked to provide them to our Customer Service Team.

For a clearer explanation of how IP addresses work and why they matter for access, take a look at our ‘IP Address Glossary’ article. It breaks down the key terms and concepts so you can understand exactly what’s happening behind the scenes.

If you have any further questions, please contact our Customer Service team.