AT&T Inc. is an American multinational conglomerate holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the world's largest telecommunications company, the largest provider of mobile telephone services, and the largest provider of fixed telephone services in the United States through AT&T Communications. Since June 14, 2018, it is also the parent company of mass media conglomerate WarnerMedia, making it the world's largest media and entertainment company in terms of revenue. As of 2018, AT&T is ranked #9 on the Fortune 500 rankings of the largest United States corporations by total revenue.

Meta is a social technology company that enables people to connect, find communities, and grow businesses. Previously known as Facebook, Mark Zuckerberg announced the company's rebrand to Meta on October 28, 2021, at the company's annual Connect Conference. Facebook was founded by Mark Zuckerberg in Menlo Park, California in 2004. With millions of more users, [Friendster] attempted to acquire the company for $10 million in mid-2004. Facebook turned down the offer and subsequently received $12.7 million in funding from [Accel Partners] at a valuation of around $100 million. Facebook continued to grow opening up to high school students in September 2005 and adding a photo-sharing feature the next month. The next spring, Facebook received $25 million in funding from [Greylock Partners] and [Meritech Capital] as well as previous investors [Accel Partners] and [Peter Thiel]. The pre-money valuation for this deal was about $525 million. Facebook subsequently opened up to work networks eventually amassing over 20,000 work networks. Finally, in September 2006, Facebook was opened to anyone with an email address. Facebook continued to receive funding most notably in January 2011 receiving $1.5 billion and valuing the company at $50 billion. A year later in February 2012, Facebook announced that it was filing for its long-anticipated initial public offering. The company went public on May 18, 2012 opening in [NASDAQ] with shares trading at $42.05. Facebook announced positive numbers in February 2012 upon filing for its IPO. As of July 2013, over 1.15 billion users have logged into Facebook every month and 669 million users daily. Mobile users now make up half of Facebook’s user base with 819 million monthly active. Facebook is one of the most trafficked sites in the United States. Additionally, Facebook is the top photo-sharing site with 250 million photos uploaded per day. The company has a strategic partnership with AXA Group to develop marketing and commercial collaboration in the digital, social, and mobile sphere. Meta is currently the owner of many applications and services such as Facebook App, Instagram, Whatsapp, Oculus VR, Pagemodo Pagebuilder, [RSS Graffiti], Huddle, and more. Facebook is the world’s largest social network with over 2.9 billion monthly active users.

BridgePort Networks, Inc. develops fixed-mobile convergence applications. The company provides MobileVoIP applications and solutions to telecommunications service providers. It provides infrastructure software that bridges mobile and voice over IP (VoIP) services with a single phone number; MobileIGNITE, a mobile to VoIP roaming solution for communications service providers; and the NomadicONE Network Convergence Gateway extends identity phone number services over multiple access networks, including mobile, cable, DSL, Wi-Fi, and other broadband networks. The company offers Dual-mode Handover, Mobile Business, Mobile IP-Centrex, and Mobile IP-PBX applications, which are designed to be used and integrated with users' current applications for communications. It serves mobile providers, integrated providers, broadband providers, and MVNO providers. The company was founded in 2002 and is headquartered in Chicago, Illinois. As of February 1, 2008, BridgePort Networks, Inc. operates as a subsidiary of CounterPath Corporation.

Expanding 4.5 million fixed lines to 20 million in just 12 years, kt introduced universal telephone service to every citizen of Korea, leading the development and advancement of communications services. More recently, kt established an advanced broadband network for the first time in Asia, and launched Korea's first communication satellite 'Mugunghwa (Sharon's Rose)', contributing to making Korea one of the most advanced countries in information and communications. Since becoming a government-funded corporation in 1997, kt changed its business portfolio to focus more on wireless and internet services instead of fixed lines. Taking over Hansol M.com and merging with its subsidiary KTF, kt expanded its business scope and included mobile communication as its main service. kt became a privately owned company in 2002 and began concentrating on building broadband network. As a result, the company set several new records including the increase of ADSL subscribers to 6 million in just 3 years and played a leading role in the age of digital networking.

magicJack VocalTec provides carrier-class voice-over Internet protocol (VoIP) solutions for communication service providers worldwide. Its Essentra product family includes Essentra CX media gateway controller that enables providers of national and international long distance services, as well as VoIP providers to build and/or migrate their infrastructure to packet-based VoIP networks, with connectivity to PSTN/SS7 services; Essentra EX peering manager, which facilitates peering between SIP and/or H.323 networks and addresses carriers' requirements in the areas of protocol interworking, security, and intelligent voice routing; Essentra BAX application server that enables the delivery of residential and hosted enterprise VoIP services over various broadband access infrastructures; and ESSENTRA OSS operation support server, a centralized Web-based management system, which enables remote management, service configuration, monitoring, and provisioning of Essentra Elements. The company develops, markets, and supports advanced telecom solutions that enable the deployment and migration of telephony networks from legacy networks to next generation packet-based networks; and implementation of Greenfield next generation telecom networks. Its solutions handle call control, media relay, signaling, and security in next-generation networks. The company's SIP-based solutions support various other protocols, including Megaco/H.248, MGCP, H.323, SIGTRAN M3UA/IUA, and SS7; and incorporate elements of the IMS/TISPAN architecture. It markets and distributes its products directly, as well as through various distribution channels to fixed-line national and international long distance carriers, competitive local exchange carriers, VoBB providers, incumbent local exchange carriers, alternative VoIP telephony carriers, Internet telephony service providers, and mobile operators.

Sprint Corp. is a holding company, which engages in the provision of telecommunications services. The company was founded in 1899 and is headquartered in Overland Park, KS.

Rubean AG develops software for highest quality and security demands of banks and all corporations, which take an active part in electronic payment. Rubean’s latest developments in the daughter company Smart Payment Solutions (SPS) GmbH enables a merchant Point-of-Sale terminal, called PhonePOS as pure smartphone app. The entire solution complies with Mastercard’s and VISA’s latest requirements. With a core staff experienced in information technology for banks, young app developers and a management which is experienced in international sales, Rubean exploit the opportunities of the dynamic smartphone environment.

Globalstar, Inc. engages in the provision of mobile satellite services. It offers voice and data communications services to the following markets: recreation and personal, government, public safety and disaster relief, oil and gas, maritime and fishing, natural resources, mining, and forestry, construction, utilities, and transportation. The company was founded in November 2003 and is headquartered in Covington, LA.

Provides telecommunications services

Mercury Corp. designs and manufactures telecommunications equipment. Its products include Fiber, Network, Access, and Voice Switch. The company was founded on August 21, 2000 and is headquartered in Incheon, South Korea.

Datang Mobile Communications Equipment Co., Ltd (hereinafter referred to as ‘Datang Mobile'), registered and established in Beijing on February 8, 2002, is one of the core members of Datang Telecom Technology and Industry Group (hereinafter referred to as ‘Datang Group'). The company headquarters in Beijing, with one subsidiary in Shanghai and one branch in Xi' an.

telent Technology Services Ltd. provides network and communications services. It offers broadband routing and switching, broadband access, and network equipment. The company is headquartered in Warwick, the United Kingdom.

BCE, Inc. is a telecommunications and media company, which engages in the provision of communication services to residential, business, and wholesale customers. It operates through the following segments: Bell Wireless, Bell Wireline, and Bell Media. The Bell Wireless segment covers integrated digital wireless voice and data communications products and services to residential and business customers. The Bell Wireline segment offers data, including Internet access and Internet protocol television, local telephone, long distance, as well as other communications services and products to residential, small and medium-sized business, and large enterprise customers. The Bell Media segment includes conventional, specialty and pay television, digital media, radio broadcasting services, and out-of-home advertising services. The company was founded on February 25, 1970 and is headquartered in Verdun, Canada.

Telefonaktiebolaget LM Ericsson engages in the provision of telecommunications equipment and related services to mobile and fixed network operators. It operates through the following segments: Networks, Digital Services, Managed Services, and Emerging Business and Other. The Networks segment supports all radio-access technologies and offers hardware, software and related services for both radio access and transport. The Digital Services segment provides software and services in the areas of digital business support systems, operational support systems, cloud communication, cloud core, and cloud infrastructure. The Managed Services segment includes networks and information technology managed services, network design and optimization, and application development and maintenance. The Emerging Business and Other segment encompasses emerging business, Iconectiv, Red Bee Media, and Media Solutions. The company was founded by Lars Magnus Ericsson in 1876 and is headquartered in Kista, Sweden.