SIP Trunking

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South Bay Communications & Security Telecommunications

Saving Customers Money Through the Power of VoIP

A SIP trunk is a VoIP connection between a private telephone system and the public switched telephone network (PSTN) using the Session Initiation Protocol (SIP) standard. SIP is an application-layer protocol that establishes and tears down communications sesstions in an IP network – from simple telephone calls to collaborative, multimedia conference sessions.

ESI SIP Trunking

ESI PhonesESI’s IP Server 900 and ESI Communications Servers support SIP trunks, provided by local Internet telephony service providers (ITSPs), as an alternative to standard analog CO trunks, T1 lines, or PRI lines. While SIP trunking offers many of the same features as traditional PSTN solutions, SIP trunking’s main attraction is its potential cost savings. These savings can include low- or no-cost calls, simplified administration, low recurring monthly charges using the same broadband data network as the Internet, and the elimination of installation and maintenance for one or more standard PSTN connections.

As with any other VoIP-based service, SIP trunking’s voice quality and reliability are highly dependent on the capabilities of the customer’s network and the provider. It is important to understand the network VoIP requirements and the capabilities of the customer network, in order to ensure that SIP trunking not only provides sufficient throughput but also minimizes latency, jitter, and packet loss. The installer also should be aware of the customer’s IP security setup, including firewall settings, and be prepared to suggest any needed enhancements — particularly regarding IP addresses that will be made publicly accessible for the purposes of SIP trunking

Feature Description

The IP Server 900 and ESI Communications Servers support both inbound and outbound calls over SIP trunks. Depending on the specific ITSP providing the service, some or all of the following features may be available:

  • “Geographic” phone numbers.
  • DID numbers.
  • E911 VoIP compliance.
  • Toll-free numbers.
  • Conference bridges.
  • T.38 fax support (IP Server 900 only).

SIP hardware, Licensing, and Capacities

The IP Server 900 supports SIP trunks natively on the main board or, if more than 64 SIP trunks are needed, through an IP Resource Module (ESI # 5000-0607). An ESI Communications Server supports SIP trunks through a SIP port card — CS-SIP24 (ESI # 5000-0547) or CS-SIP8 (ESI # 5000-0550). Each IP Server 900 and each ESI Communications Server SIP card requires SIP licenses to operate, and each SIP trunk requires one license. ESI sells SIP trunk licenses for ESI Communications Servers in increments of eight (ESI # 5000-0546), with up to 24 licenses activated on any SIP card. Each SIP trunk license will consume available lines/trunk capacity for the system.

SIP Programming

Programming of SIP trunks is performed by an IP-certified ESI Reseller, using Function 214. Variables for each SIP trunk are entered, as well as information about the SIP account held with the ITSP. The procedure is relatively simple: first, pick the provider; and then pick the trunk type. Although different trunk type selections require different entries, ESI system software automatically suppresses unused data fields, thus further simplifying the programming process. Up to 1,200 DID numbers (10-digit) are supported, depending on system type. DID/DNIS translations for SIP trunks are supported in the pilot table, which supports 10-digit numbers and up to 100 pilot numbers per system. SIP trunk security, signaling, and IP addressing information are entered in system Function 8 (IP programming). Programming steps for SIP trunks may vary by approved interoperable ITSP.

More On SIP Trunking

Make the Case for SIP Trunking
SIP Trunking combines voice and data traffic onton a single network by effectively substituting an Internet connection for conventional phone trunks.

SIP Trunking 101: How Does It Work?
An infographic giving basic information on how SIP trunking works including how connections are made and how a call travels from place to place.

SIP Trunking Gets Down to Business
An infographic explaining how SIP trunks enable advanced IP features to work across locations, reduce communications costs and efficiently use bandwidth.

ISDN vs. SIP Trunking: How They Stack Up
An infographic showing why SIP Trunking offers advantages over ISDN PRI trunks when connecting calls with your IP phone system to the public telephone network.

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All South Bay Communications & Security installations are guaranteed to be 100% operational before we consider the job complete.  All cables are well labeled and certified and are installed according to BICSI standards.

If you are in the market for, or need service on, Toshiba, ESI, or Telrad telephone systems or other communications products contact ustoday and schedule a no-obligation consultation or quotation. As a local company headquartered in Chesapeake, we respond immediately to client needs in Virginia Beach, Chesapeake, Norfolk, Portsmouth, Suffolk, Newport News, Hampton, throughout Hampton Roads as well as Northeast North Carolina.

About Our Technology Solutions
South Bay Communications & Security provides a variety of communications services and products such as Toshiba, ESI, Telrad, Business Telephone Systems, IP Phones, VOIP, Voice Over IP, Sip, Sip Trunks, PRI, Headsets, Wireless Headsets, Paging, Overhead Music, Sound Systems, Structured Cabling, Cat 5/5e/6, Category 5/5e/6, Fiber Optics, Smart Boards, and more. Our communications company serves clients in Virginia Beach, Norfolk, Chesapeake, Portsmouth, Hampton, Newport News, Suffolk, Williamsburg, Isle of Wight, Hampton Roads, Richmond, Virginia, North Carolina, Maryland, Baltimore, DC, and more.

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