Yeastar S-Series SIP Trunk Configuration
Simtex SIP Trunks from $4.99/month
Business-grade SIP trunking with geo-redundant infrastructure, crystal-clear audio, and Australian-based support. Pay-as-you-go or unlimited plans available.
SIP Servers:
- West Coast (AU):
siptcp.simtex.com.au - East Coast (AU):
siptcpeast.simtex.com.au
Choose the server closest to your PBX. The S-Series supports DNS-NAPTR transport for automatic server discovery and failover.
Do not expose your PBX to the public internet. In 99.9% of cases you do not need any ports forwarded on your router or firewall to connect to Simtex. If you are unsure, speak to us first.
S-Series vs P-Series: If you have a Yeastar P-Series (P550/P560/P570), use our Yeastar P-Series guide instead. The P-Series has a different menu layout and updated terminology.
Trunk types explained: The S-Series calls these VoIP Register Trunk, VoIP Peer Trunk, and VoIP Account Trunk. Select Register Trunk for Simtex — the PBX authenticates with your account credentials and registers with our SIP servers.
DNS-NAPTR for automatic failover: Instead of selecting TCP as the transport, you can select DNS-NAPTR and set the port to
0. The PBX will query DNS SRV/NAPTR records to automatically discover the correct server, port, and transport — providing automatic failover across our geo-redundant server farms.East Coast? Replace
siptcp.simtex.com.au with siptcpeast.simtex.com.au in both the Hostname/IP and Domain fields if your PBX is located on the East Coast of Australia (NSW, VIC, QLD).Realm field: The S-Series has a Realm field that defaults to
YSAsterisk. Clear this field (leave it blank) to avoid registration failures. An incorrect Realm value will cause your trunk to fail authentication with a 401/407 error.Channel security: Set Maximum Channels to the number of concurrent calls you actually need. This acts as a hard limit — if your system is compromised, attackers can't exceed this call count.
G.711 A-Law is the standard codec for Australian PSTN interconnection. It provides toll-quality audio at 64kbps with zero transcoding overhead. Always place it first.
Recommended Dial Patterns for Australian Numbering
| Description | Dial Pattern | Strip | Prepend | Example Dialled |
|---|---|---|---|---|
| Local (8-digit with area code) | XXXXXXXX | 0 | 94883344 | |
| National / Mobile (leading 0) | 0XXXXXXXXX | 0 | 0412345678 | |
| Emergency | 000 | 0 | 000 | |
| 1300 / 1800 Numbers | 1[38]00XXXXXX | 0 | 1300888519 | |
| 13 Numbers (6-digit) | 13XXXX | 0 | 131313 | |
| International (0011) | 0011. | 0 | 001161894883344 |
International dialling: If you do not need international calls, simply leave out the
0011 dial pattern. This is the simplest way to prevent unauthorised international dialling and potential toll fraud.Wildcard syntax: Yeastar uses Asterisk dial pattern notation.
X matches any digit 0–9, Z matches 1–9, N matches 2–9, and . matches one or more characters.Trunk not registering? Check these common issues:
- Verify your account number (
214XXXXXXX) and password — copy/paste to avoid typos - Ensure the Realm field is blank (not the default
YSAsterisk) - Confirm the Transport is set to TCP on the trunk
- Check your firewall allows outbound TCP connections
- Try the alternate server (
siptcpeast/siptcp) in case of regional issues - Verify DNS resolution: the hostname must resolve to a valid SIP server
Always disable SIP Guest calls on production systems. Leaving this enabled allows unauthenticated callers to place calls through your PBX — one of the most common causes of toll fraud.
Caller ID validation: Simtex validates outbound caller IDs against your account. Only DIDs allocated to your trunk will be transmitted — any other number is replaced with your main trunk number automatically.
Common Questions
Register Trunk. Simtex uses credential-based authentication. Your PBX registers with our SIP servers using your account number and password. Peer Trunk is only used when a provider authenticates by IP address.
Last updated 30 March 2026