You can have racks, routers, servers, switches, and clean configs — but none of that makes your network reachable from the public internet by default.
For that, you need IP transit.
IP transit is the service that connects your autonomous system to the rest of the internet. Your upstream provider carries your traffic to other networks and announces your prefixes so return traffic knows how to find you.
In other words: transit is what turns your network from an isolated island into part of the global routing system.
How IP Transit Works
At the technical level, IP transit usually looks like this:
- Your router connects to the transit provider’s router.
- You establish a BGP session.
- The provider sends you routes, often the full internet routing table.
- You announce your own prefixes.
- The provider propagates those announcements to its peers and upstreams.
That last step matters a lot. Sending traffic out is only half the job. If your prefixes are not announced correctly, the rest of the internet will not know how to send traffic back.
For IPv4, the practical minimum is usually a /24, because smaller prefixes are commonly filtered.
Transit vs Peering
Transit and peering are related, but they solve different problems.
IP transit gives you reachability to the whole internet. You pay a provider, usually per Mbps, and they carry your traffic globally.
Peering lets you exchange traffic directly with another network, often through an internet exchange. It is great for cost and latency when you have enough traffic with specific networks, but it does not replace transit for most operators.
The common path is simple:
Start with transit. Add peering later when traffic volume makes it worth it.
What You Need Before Buying Transit
Before a transit provider can bring you online, you typically need:
- An ASN to identify your network in BGP
- A BGP-capable router
- An upstream/transit agreement
- IPv4 and/or IPv6 address space you are allowed to announce
- Correct routing objects and, ideally, RPKI ROAs
The first three are usually straightforward.
IPv4 is where things often slow down.
The IPv4 Problem
IPv6 is available. IPv4 is not.
In the RIPE region, the free IPv4 pool has been exhausted for years. If you need IPv4 today, your main options are:
- Wait for allocation
- Buy space on the transfer market
- Lease IPv4 blocks
Each option has trade-offs.
Waiting can take a long time. Buying requires upfront capital. Leasing gives operators a faster way to get announceable address space without locking themselves into a large purchase.
For hosting providers, ISPs, CDNs, and infrastructure teams, this can be the difference between launching now and waiting months.
Pricing Is Not Just “$/Mbps”
IP transit pricing is usually quoted per Mbps per month, but the number depends on context:
- Commit size
- Location
- Provider tier
- Billing model
- SLA
- DDoS protection
- Route quality
- Redundancy
A low price in a major hub at 100 Gbps does not mean the same price exists for a small commit in a less connected market.
Also, cheaper transit is not always better transit. Bad routes, weak support, or poor visibility can cost more than the savings.
Practical Takeaway
IP transit is the foundation of public internet reachability.
To bring a network online, you need more than bandwidth. You need BGP, an ASN, upstream connectivity, route propagation, and address space that the global internet will accept.
And in many real deployments, IPv4 becomes the bottleneck — not the router, not the contract, and not the cross-connect.
So plan for IPv4 early. If your network depends on it, your rollout timeline probably does too.
Full version: What Is IP Transit?
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