Migrating from TDM PSTN trunks to SIP PSTN: Challenges
Migrating to SIP trunking is a strategic decision for the enterprises. when adopted in right way it can provide flexibility to address immediate and future collaboration needs. However, SIP adoption comes with its own set of challenges including:
Installation complexity: Lack of uniform standards and substantial protocol, complex configuration, and behavioral makes move between different SIP Trunking solution a challenge. Leveraging (Enterprise session border controllers) eSBC can help mitigate these issues.
Need for robust WAN infrastructure: To effectively support SIP trunking, organizations need a robust WAN to prevent latency and jitter issues.
Lack of expertise and support: Organizations need to leverage right level of expertise – either in house or through a provider – to customize SIP trunking solution based on organizational needs.
Current Telephony Deployment Approach if Costly and Has Higher Call Rates
In a typical telephony deployment, a bunch of physical wires are delivered from the PSTN service provider to the enterprise. However, TPSTN circuits require high investment to purchase ISDN, BRIs, PRIs or local PSTN gateways, have fixed channels for voice calls and seldom offer buffer. In addition, inefficient least cost routing, lower flexibility to add more lines and parallel infrastructure in addition to IP WAN network adds to the complexity.
Leveraging Right SIP Trunk Model for Enhanced Flexibility and Cost Optimization
SIP trunk allows enterprises to replace these traditional PSTN lines with PSTN connectivity through SIP trunking service. Some of the models include:
Centralized SIP Trunking
In central SIP trunking, only central office location has the direct SIP connectivity to the IP PSTN where all external calls to or from remote sites go through the central location (see figure.1). Centralized SIP trunking requires higher bandwidth for connectivity to both the IP PSTN and the private WAN to service all remote sites.
The main benefits of centralized SIP tracking include: