# IP Pools

Every subscriber needs an IP address when connecting. SAS Radius supports two ways to assign addresses, chosen per profile with **IP Pool Mode**:

<table id="bkmrk-ip-pool-modewho-assi"><thead><tr><th>IP Pool Mode</th><th>Who assigns the IP</th><th>When to use</th></tr></thead><tbody><tr><td>**Use NAS IP Pools** (default)</td><td>The router. SAS Radius only sends the **Pool Name**; the pool must exist on the router with the same name.</td><td>Most networks, especially with one router or pools that differ per router.</td></tr><tr><td>**Use SAS4 IP Pools**</td><td>SAS Radius, from pools created in *IP Pools*. The router receives the exact IP for each user.</td><td>To manage all address ranges in one place instead of on every router.</td></tr></tbody></table>

## IP Pools list

Open *IP Pools* in the menu. The list shows each pool's **Pool Name**, **From IP**, **To IP** and **Lease Time (hours)**. Search by name or IP. Click a pool name to edit it.

[![ippool list](https://help.snono-systems.com/uploads/images/gallery/2026-11/scaled-1680-/ippool-list.png)](https://help.snono-systems.com/uploads/images/gallery/2026-11/ippool-list.png)

## Creating a pool

Click **Actions → New**, fill in the form and click **Submit**.

[![ippool form](https://help.snono-systems.com/uploads/images/gallery/2026-11/scaled-1680-/ippool-form.png)](https://help.snono-systems.com/uploads/images/gallery/2026-11/ippool-form.png)

<table id="bkmrk-fielddescription-poo" style="width: 100%;"><thead><tr><th style="width: 16.8077%;">Field</th><th style="width: 83.1676%;">Description</th></tr></thead><tbody><tr><td style="width: 16.8077%;">Pool Name</td><td style="width: 83.1676%;">Required and unique, for example <code>pool&#45;20M</code>.</td></tr><tr><td style="width: 16.8077%;">Lease Time (hours)</td><td style="width: 83.1676%;">How long an address stays reserved for a user (default 1).</td></tr><tr><td style="width: 16.8077%;">Start IP</td><td style="width: 83.1676%;">First address of the range, for example <code>10&#46;20&#46;0&#46;1</code>.</td></tr><tr><td style="width: 16.8077%;">End IP</td><td style="width: 83.1676%;">End of the range, for example <code>10&#46;20&#46;3&#46;255</code>. It must be after the Start IP. The pool contains the addresses from Start IP up to, but not including, End IP.</td></tr></tbody></table>

- Large ranges take a little longer to save, because every address is prepared.
- Editing a pool rebuilds its address list.
- **Deleting** a pool also removes it from all profiles that use it; those profiles go back to *Use NAS IP Pools*.

*Required permission: Managers - System Administrator*