VoIP
Asterisk
Open-source telephony engine used where dial plan logic, integrations and call flow behaviour need to be fully controlled.
Capabilities
What we implement
- Custom dial plan logic
- AMI / ARI integration
- Codec and transcoding strategy
- Queue and IVR design
Security
How it is hardened
- TLS signalling and SRTP media
- Fail2ban and source restriction
- Outbound route limits against toll fraud
Editions & pricing
Asterisk editions and vendor pricing
Vendor list prices for the editions we deploy. Deployment, migration, hardening and support are quoted separately by Techno Trader PK — they are never bundled into these figures.
| Edition | Licensed by | Vendor list price |
|---|---|---|
| Open-source coreAsterisk is free and open source under the GPL. Cost is engineering, hardware and carrier spend. | licence cost | $0 |
Prices are checked against the vendor's published price list. Last verified 9 Sept 2026. Vendor list prices exclude tax and can change without notice. Vendor pricing page
Architecture
Asterisk reference architecture
Asterisk sits behind a hardened border, with dial plan logic and integrations kept in version-controlled configuration rather than ad-hoc GUI changes.
01 · Carrier & PSTN
Primary SIP trunkBackup SIP trunkGSM / PRI gatewayRegistration or IP authentication per trunk, with failover routes and CLI presentation rules.
02 · Border
Edge firewallSIP ALG disabledFail2ban / rate limitsOnly carrier and known extension ranges reach 5060/5061; TLS for signalling, SRTP for media.
03 · Asterisk core
PJSIP endpointsDial plan contextsQueues & IVRAMI / ARIContexts separate internal, outbound and restricted classes; ARI/AMI exposed only to the application host.
04 · Data & integrations
CDR databaseRecording storageCRM connectorCDR and recordings written to a separate volume with retention and access controls.
05 · Endpoints
Desk phonesSoftphonesRemote agentsProvisioning templates per device model; remote users routed via VPN or SBC rather than open SIP.
FAQ
Asterisk questions we are asked
- When is raw Asterisk a better fit than FreePBX?
- When call flow logic is genuinely custom — routing driven by external data, complex integrations over ARI, or logic that must live in code review and version control. If the requirement is standard extensions, queues and IVR, a managed interface is cheaper to operate.
- Which SIP stack should new deployments use?
- PJSIP. It is the maintained channel driver and handles multiple contacts per endpoint, per-endpoint transports and TLS more predictably than the legacy chan_sip driver.
- How do you stop toll fraud on an Asterisk box?
- Strong per-device secrets, restricted outbound contexts, no default 'allow all' dial patterns, source-restricted SIP ports, fail2ban on registration failures, and spend/concurrency limits agreed with the carrier.
- Can Asterisk run in a virtual machine?
- Yes, with pinned CPU resources and attention to timing. Oversubscribed hosts cause jitter and audio artefacts, so voice VMs get reserved compute and are kept off noisy storage tiers.
Related
Other voip platforms
Asterisk is referenced to describe engineering capability. All trademarks and product names are the property of their respective owners; no partnership or endorsement is implied.
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