RashComm Pvt. Limited

Airport House, Purley Way

Croydon CR0 0XZ

(+44) 0208 405 2545


SIP Connectivity

RashComm Solutions provides a SIP hand-off to your LAN and IP PBX. As a result, the SIP voice traffic does not need to be converted to a traditional protocol like ISDN PRI or CAS, eradicating the need to purchase T-1 cards and infrastructure equipment such as terminating gateways and channel banks.

A Powerful but Evolving Protocol

SIP requires cooperative interoperability testing and support between service providers and equipment manufacturers. Not all SIP-enabled equipment works seamlessly together. However, we thoroughly test interoperability with each IP PBX system we certify and provide clear documentation to customers and their equipment vendors on how to provision a system to support SIP trunks on the TelePacific network. In addition, to support firewall protection, we’ve standardized on the Cisco ISR series, leveraging Cisco’s Unified Border Element (CUBE) to enable customers to keep or deploy any firewall they choose to protect their LAN.

A SIP trunk is a service offered by an ITSP (Internet Telephony Service Provider) that connects a company’s PBX to the ordinary public switched telephone network (PSTN) via the Internet using the SIP Voice-over-IP (VoIP) standard.

Many enterprises want to make full use of their installed IP PBXs and not restrict themselves to communicating over IP only within the enterprise. A SIP trunk provided by an Internet Telephony Service Provider (ITSP) connecting the enterprise to the traditional PSTN network is the solution. Unlike traditional telephony, where bundles of physical wires were once delivered from the service provider’s central office to a business, a SIP trunk allows a company to replace these traditional fixed PSTN lines with PSTN connectivity via a SIP trunking service provider over the Internet.


Via the Internet Protocol, the ITSP provides connectivity to the PSTN (Public Switched Telephone Network) for communication with mobile and fixed phones.

By combining multiple ITSPs and managing them seamlessly within the RashComm Solutions MX platform, SIP trunks can offer significant reductions in operating expenses for enterprises, eliminating the need for local PSTN gateways, costly ISDN BRI (Basic Rate Interface) circuits, and PRI (Primary Rate Interface) digital trunking services.

Certified ITSPs

RashComm Solutions has tested and certified many ITSP providers for interoperability with the MX platform. Each provider supplies RashComm Solutions with a full connection which is used to perform an exhaustive battery of use case tests in order to certify all aspects of the ITSP’s functionality. A few of the elements tested and certified include:

  • Registration – Authorization
  • Call flow (inbound/outbound)
  • Call forwarding/call transfer (internal/external)
  • Call park and pickup
  • Conference calling
  • DTMF transmission reliability and recognition
  • Voice quality