Set up Grandstream UCM in Reachable
WorksGrandstream UCM is a phone system your company runs itself. This is how you add your Grandstream UCM account to Reachable, so your phone rings, even with the app closed.
- You enter: Extension, SIP password and PBX address.
- The password: the extension's SIP/IAX Password, not the password for the web portal or the Grandstream app.
- Up to 3 devices per account at a time.
What to enter
From version 1.1 Grandstream UCM is in the app's list. Pick Grandstream UCM and fill this in; the app fills in the other settings itself.
Where to find your details
- Ask your administrator.
- On the UCM: Extension/Trunk > Extensions > your extension.
- You need the extension number, the SIP/IAX Password and (if set) the Auth ID, plus the external address of the PBX.
Right now: with Other SIP provider
In version 1.0 Grandstream UCM is not in the list yet. Choose Other SIP provider and fill this in. The fields marked (optional) are under Advanced.
| Field in the app | What to enter |
|---|---|
| Username | exactly as in your portal, for example 1000 |
| Password | your SIP password (see above) |
| Server or domain | the address from your portal, for example pbx.bedrijf.nl |
| Transport | UDP |
| Port (optional) | leave empty |
| Outbound proxy (optional) | leave empty |
| Separate login name (optional) | your auth ID from the portal |
| Voicemail number (optional) | leave empty |
Encrypted calls
Grandstream UCM can encrypt your calls. Under Advanced choose Transport TLS, port 5061 and switch on Encrypt the sound (SRTP). On iPhone a lock then shows during the call.
Good to know
- Up to 3 devices at a time. Grandstream UCM lets up to 3 devices sign in on one account at the same time. Reachable on two phones counts as one device: only our server signs in at Grandstream UCM.
- Our server signs in from Germany, from 2.28.204.233 and 167.233.187.96. If the UCM blocks countries (Country/Region IP Defense) or addresses after failed tries (Fail2ban), ask your administrator to allow those addresses.
- By default three devices may be signed in on one extension at the same time. Your administrator can raise that to ten (Concurrent Registrations).
- The PBX must be reachable from outside on an external address, such as pbx.company.com.
Help
Grandstream UCM also explains it in its own help: Grandstream UCM guide (documentation.grandstream.com). Not working? See What Not reachable means or email us at info@abn.company.
Checked on 12 October 2026 against Grandstream UCM's own manuals. Is something out of date? Email us and we will fix it.