How to Lease IP Addresses Without Losing Operational Control

A dependable lease is a sequence of checks, responsibilities and an exit path.

Start with the service, not the address count

Before you ask how many IP addresses to lease, write down what the service must do. Which systems need public IPv4? Where will they run? Who will operate them? How quickly could demand change?

A lease gives a company the right to use addresses for an agreed period. It does not by itself make the service reachable, the records accurate, or the exit easy. The useful goal is a working service whose dependencies remain visible when the business changes direction.

Choose a block that matches the workload

A prefix is a group of addresses described together. A /24 contains 256 address values and a /23 contains 512, but those counts are not automatically the number of customers or servers you can support. The network design determines that.

Turn the service plan into an address requirement. Separate customer-facing systems, management, testing and expected growth. Renting a familiar block size without doing this work can leave you paying for capacity that does not fit the service.

Know what the provider and registry each control

A holder, hosting company, broker or specialist provider may be involved in a lease. A Regional Internet Registry maintains number-resource records and related services; its allocation and transfer processes are different from a commercial lease.

Ask who will route the prefix, who can authorise that route, who maintains registration information and reverse DNS, and who can change the technical contacts. A letter of authorisation can document an intended arrangement, but it is one piece of evidence. It does not prove the whole history of a block or guarantee that the service will work.

IPv4 scarcity also needs to be understood carefully. Note 45 distinguishes an exhausted first-allocation pool from addresses that remain in use and can move through existing markets. Scarcity explains why planning matters; it does not decide that every company must buy immediately.

Read Note 45, On the Manufactured Narrative of IPv4 Scarcity

Check the actual addresses before activation

Review the specific block you are being offered. Check registration details, recent routing history and reputation signals that matter to your workload. Email has blocklists and delivery requirements; a web service has application paths, access controls and partner allowlists.

There is no single clean label that proves suitability for every use. A result from one reputation service is an observation, not a universal verdict. Agree in advance who investigates a problem, how that person can be reached and what evidence will be preserved.

Test the route and the service together

The intended network should announce the prefix, and relevant external networks should be able to reach it. BGP is the protocol used to announce how traffic can arrive. An Autonomous System Number identifies a network in that process.

A Route Origin Authorisation records which ASN is authorised to originate a prefix. RPKI origin validation checks the announced origin against that record; it does not validate the entire path or guarantee that every network will accept a route.

Test DNS, application access, monitoring and partner allowlists as well. Start with a controlled deployment, verify the results, then expand. A completed payment or a delivered address list is not the same thing as working connectivity.

Read Note 66, Why i.LEASE Exists

Make ongoing responsibility visible

Keep a short operating record: the prefix, the services using it, registry and routing contacts, renewal date, and the person responsible for each change. Decide how faults and abuse reports reach someone who can act.

Network identity becomes more valuable as customers and systems learn to recognise it. Note 68 explains why continuity is an economic asset, not a detail to leave to a lease contract. A provider should protect that continuity while also making the records and handoffs understandable to the customer.

Read Note 68, The Economics of Network Identity

Rehearse how you would leave

Think through the end of the arrangement while you still have time. Which DNS records, firewall rules, customer allowlists and partner systems depend on these addresses? Which changes need another organisation’s help? Arrange overlap, test a replacement path and verify customer access before retiring the old route.

A plan to change providers does not automatically mean the leased addresses can move with you. Establish what can remain, what must move and who performs the work. Note 72 gives the wider test: coordination should protect uniqueness and accurate records while keeping the administrator replaceable.

If the business needs capacity now but its shape is still changing, lease first when the provider offers a clear record, route, support and exit path. Consider buying when demand is durable enough to justify capital and the company is prepared to own the operational work. For the commercial tradeoff behind that choice, continue with the guide to why startups lease before they buy.

Read Note 72, The Bill of Rights of Uniqueness Coordination

Continue with Why Startups Lease IP Addresses Before They Buy