SIZE XSAsterisk and Freeswitch are each versatile, open source platforms for building customizable voice over IP ("VOIP") communications applications. Analogous to webservers that accept requests and render responses according to scripted instructions, these platforms accept requests and process communications channels according to scripted instructions known as "dialplans". At the heart of these platforms is the capability to route phone calls and video streams according to dialplan specifications, and typical available applications include office phone systems ("PBX"), voice mail, auto-attendant, interactive voice response ("IVR"), conferencing, call centers, and SIP/PSTN gateways. Many organizations employ these platforms for their internal requirements in lieu of proprietary equipment, and service providers often deploy proprietary services customized and architected to specific market needs.

These platforms run preferably on Linux and can be installed on premises, co-located at telecom hotels, or deployed on cloud services. Careful attention must be paid to proper TCP/IP trunking for VOIP traffic levels, and specialized gateway hardware is required for connectivity to PSTN circuits.

Hotlynx can help configure and deploy Asterisk and Freeswitch for your business needs, including the development of dialplans and extending functionality with custom features.

WebRTC enables real time communications between workstations from within web browsers, and provides the capability to exchange voice, data and video using peer-to-peer connections, thus eliminating server load and bandwidth bottlenecks. It is ideal for chat and conferencing applications, and can interoperate with traditional telephone communication networks when operating with a compatible SIP signaling system, such as Asterisk or Freeswitch.

Now JavaScript in your web pages can manage the entire communications process, with simplified code thanks to the WebRTC API. Traditionally complex tasks are handled under the hood, including capturing streams from microphones and cameras, encoding, echo cancellation (AEC), automatic gain control (AGC), noise reduction, concealment of packet loss and jitter. Also included are provisions for establishing peer connections and support of proxies.

A search for "PSTN advantages over SIP" will likely produce only converse results, highlighting the advantages of SIP. Searching more specifically for "SIP disadvantages" will explain why one might wish to avoid Systematic-Investment-Plans. Clearly, SIP is the sweetheart of the telecom industry yet there are some specific circumstances where PSTN answers the call. Such situations might arise if enhanced features are required for an existing PSTN facility, if appropriate SIP trunking is unavailable, or if the inherent propagation delays associated with SIP voice channels cannot be tolerated. SIP platforms are also more susceptible to fraud and security breaches than PSTN facilities. 

In such cases, Dialogic Media Boards help to implement large-scale call processing, such as unified messaging, call center, announcement, and IVR services.

Trunks, gateways, routers, switches, VOIP phones, etc. all require facilities for configuration, control and monitoring. User interfaces for these functions are often rendered via web browsers. In many cases the architecture of a network component includes a web server so that UI functions can be accessed at secure URI's. The Drupal content management system ("CMS") provides many of the building blocks and resources necessary to create reliable and secure network management, monitoring and user interfaces. Drupal's "headless" mode provides secure URI's for interacting with and reporting to centralized command and control facilities.

When a telecom facility is operated as a profit center, services rendered must be measured and billed. The Drupal CMS provides a versatile full featured E-Commerce framework that is extremely customizable and dependable. It is capable of managing back office functions related to invoicing, collection, merchant account management, customer care, fraud avoidance and much more.

Interoperability of mobile and browser Apps is critical in today's unified communications ("UC") markets. A product's potential may be limited if it requires mobile users to access its functions only through browser interfaces. The Drupal CMS provides a "headless" mode that enables decoupling the presentation from content. With headless Drupal, applications running on the client side take care of direct user interface and consume content through a standardized portal using Drupal's powerful RESTful web services interface.

Hotlynx offers extensive experience applying the Drupal CMS, implementing network management, E-Commerce, and RESTful web services applications.

Cross platform applications implemented in native code require multiple code bases, complicating and driving up the costs of development, support and maintenance. Apps for browsers, and mobile IOS and Android devices typically employ JavaScript, Swift and Java code bases respectively. Native Apps can be optimized to take full advantage of specialized device features and to provide native look and feel of the device on which they execute.

Hybrid Apps employ a single, usually JavaScript, code base for all platforms. The core App operates within a native code wrapper running on the target device. The wrapper presents a unified application programming interface ("API") and decouples the device characteristics from the core App so that a single code base can execute within the appropriate wrapper on all supported devices. Cordova/Phonegap provides native wrappers for many popular mobile devices and supports core Apps written in standard JavaScript. This strategy often permits JavaScript Apps written for a browser to be ported to mobile devices with few modifications.