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What Is SIP Trunking?



What Is SIP Trunking?


For enterprises wanting to make full use of their installed IP-PBXs and not only communicate over IP within the enterprise, but also outside the enterprise a SIP trunk provided by LegacySIP to connect to the traditional PSTN network is the solution. Unlike in traditional telephony, where bundles of physical wires were once delivered from the service provider to a business, a SIP trunk allows a company to replace these traditional fixed PSTN lines with PSTN connectivity via LegacySIP SIP trunking service provider on the Internet.


LegacySIP SIP trunks can offer significant cost-savings for enterprises, eliminating the need for local PSTN gateways, costly ISDN BRIs (Basic Rate Interfaces) or PRIs (Primary Rate Interfaces).


The potential for a rapid return on investment is a key driver of SIP trunk deployments. In terms of infrastructure purchases, SIP trunks provide an immediate cost-savings. They eliminate the need to purchase costly BRIs, PRIs or PSTN gateways.


The productivity benefits with SIP and SIP trunking are significant. By extending the SIP capabilities of the corporate network outside the LAN, satellite offices, remote workers and even customers can use VoIP and other forms of real-time communications applications to break down barriers of geography to share ideas and increase productivity.


There are three components necessary to successfully deploy SIP trunks: a PBX with a SIP-enabled trunk side, an enterprise edge device understanding SIP and LegacySIP’s SIP trunking service.


The PBX In most cases the PBX is an IP-based PBX, communicating with all endpoints over IP, but it may just as well be a traditional digital or analog PBX. The sole requirement is that an interface for SIP trunking connectivity is available.


The enterprise border element


The PBX on the LAN connects to LegacySIP VoIP via the enterprise border element.  The enterprise edge component can either be a firewall with complete support for SIP or an edge device connected to the firewall, handling the traversal of the SIP traffic.


LegacySIP VoIP on the Internet


LegacySIP VoIP (the Internet Telephone Service Provider) provides connectivity to the PSTN (Public Switched Telephone Network) for communication with mobile and fixed phones.


Voice quality is not an issue with SIP trunking if proper Quality of Service (QoS) measures are applied, such as over provisioning of links, and prioritization of voice traffic. Reliability is also a moot point. In fact, LegacySIP trunks can be more reliable than the traditional PSTN as a number of failover solutions can be implemented. LegacySIP has the experience necessary to assure you of high quality voice over your network. We can work with you remotely or on site to address both your voice and network needs.


LegacySIP SIP trunking delivers several benefits:


·         Eliminates costly BRIs (Basic Rate Interfaces) and PRIs (Primary Rate Interfaces) subscriptions


·         No need to invest in PSTN gateways and additional line cards as you grow


·         Optimal utilization of bandwidth by delivering both data and voice in the same connection


·         Maximum flexibility in dimensioning and usage of lines as you avoid having to buy capacity in chunks of 23 (T1)


·         Redundancy with multiple service providers and links


·         Sip trunks can allow for immediate reduction in call costs and help an enterprise maximize their legacy PBX investment while providing profit enhancing features to their users:


·         Voicemail to e-mail


·         Fax to e-mail


·         Follow me features so that calls are never missed


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Article details
Article ID: 65535
Category: Knowledgebase
Date added: Jul-09-2012 20 8:55pm
Views: 664
Rating (Votes): Article rated 3.0/5.0 (44)

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