This guide is for the Gigaset N510 IP PRO base using its documented web configurator. It does not cover the N670/N870 multicell interface. The N510 is an older model: check its support and firmware situation before choosing it for a new installation. Do not downgrade software to match a screenshot in an old manual.
Prepare the IllyVoIP line
Open SIP Lines and obtain the SIP username, SIP password and server for the line you intend to connect. These are not your Portal email and login password. This walkthrough uses password authentication. If the existing line uses IP authentication, do not switch modes without checking which devices depend on it.
A separate device can use a separate SIP line; review any subscription charge before confirming. Keep a note of which device uses each line, but do not put passwords in shared documents. When replacing a working phone, keep its configuration privately so you have a way back if the new setup needs troubleshooting.
Open the base configuration safely
Connect the base to your trusted network, pair a compatible handset using its manual and find the base IP from the device/network information. Open that address in a local browser and sign in with the base’s administrator access. The base/system PIN is different from the SIP password. If your company manages the device, ask the administrator before modifying its connections.
Create the VoIP connection
Open Settings → Telephony → Connections and edit a free IP connection. Enter the line’s authentication name, authentication password and username. Use the IllyVoIP connection details for domain/registrar/server fields rather than another operator’s downloaded profile. Save and activate the connection, then check whether its status becomes registered.
Choose send and receive connections
Under Settings → Telephony → Number Assignment, decide which connection each handset uses to place calls and which connections it receives calls from. Save your choices. A handset can be paired to the base without being assigned the connection you just created.
Example: two rooms, different ringing
Imagine a handset at Reception and another in a meeting room. If only Reception should answer the business number, assign that receiving connection there first. Check the outgoing connection separately for both handsets. Test the intended behavior with a call from a phone outside the base; an internal call between handsets does not verify IllyVoIP registration or incoming-number routing.
Do not confuse three different credentials
The base login protects device settings. The SIP credentials connect the base to IllyVoIP. Your Portal login opens your IllyVoIP account. Changing one does not automatically change the others. If a saved SIP password is hidden or shown as a placeholder, do not assume it has been erased; check registration before replacing it.
When only one direction works
If outgoing calls work but incoming calls do not, check receiving assignments, handset Do Not Disturb and the number’s Portal destination. If the handset uses the wrong account when dialing, inspect its sending connection. If all handsets lose registration together, start with the shared network/base connection rather than changing every handset separately. Keep a private record of the previous assignment so a test does not leave another room without calls.
Match signaling and audio settings
Use the server, destination port and transport supplied for your line. The device’s local IP opens its administration page; it is not the IllyVoIP server address. SIP signaling and audio encryption are separate choices. The Portal audio mode must match the device’s supported configuration: Standard RTP, SDES-SRTP or DTLS-SRTP. Do not change encryption just because an unrelated tutorial uses another setting.
Keep the administration page on a trusted network. Do not expose it to the Internet or disable a firewall to make a test work. If your model does not offer a required option, ask about that exact model and firmware instead of changing several unrelated settings at once.
Verify the result one step at a time
- Registration: check the device’s account status. A familiar name on its screen is not proof that it is registered.
- Outgoing call: select the IllyVoIP line and call a number you control in international format. Check balance and destination rates first; the test may be chargeable.
- Audio and identity: speak in both directions and check the outgoing caller ID. Editing a local display name does not grant permission to use another number.
- Incoming call: route an active phone number to this SIP line and call it from another device. SIP registration does not automatically choose a number’s incoming destination.
What to check before contacting Support
If registration fails, check the line details before changing the network. If registration succeeds but a call is rejected, check number format, balance, routing package and permitted caller ID. If the call connects without audio, report that distinction: it is a different problem from failure to register.
Include the device model, firmware version, time and timezone, visible error and public call reference where available. The SIP response-code guide helps explain errors. Never send passwords, unmasked configuration exports or screenshots containing customer data.
Documentation and scope
Device configuration reference. Menu paths were checked against documentation and Portal steps against IllyVoIP. This is not physical-device certification; the Portal screenshot is not a screenshot of the phone administration interface.