Another legal issue that the US Congress is debating concerns changes to the Foreign Intelligence Surveillance Act. The issue in question is calls between Americans and foreigners. The National Security Agency (NSA) is not authorized to tap Americans' conversations without a warrant—but the Internet, and specifically VoIP does not draw as clear a line to the location of a caller or a call's recipient as the traditional phone system does. As VoIP's low cost and flexibility convinces more and more organizations to adopt the technology, the surveillance for law enforcement agencies becomes more difficult. VoIP technology has also increased Federal security concerns because VoIP and similar technologies have made it more difficult for the government to determine where a target is physically located when communications are being intercepted, and that creates a whole set of new legal challenges.[68]
Typically, price is one of the most important reasons people opt for residential VoIP. One of the most attractive is the "triple play" sales pitch we mentioned above made by almost every regional residential cable company and internet provider: Get your Internet, TV, and phone service all rolled into one monthly charge. Not only is that usually an attractive number, it also means a technician will hook everything up for you including your phone, and you'll probably be able to use the same phone you're using now instead of having to migrate to a VoIP phone.
On the early ARPANET, real-time voice communication was not possible with uncompressed pulse-code modulation (PCM) digital speech packets, which had a bit rate of 64 kbps, much greater than the 2.4 kbps bandwidth of early modems. The solution to this problem was linear predictive coding (LPC), a speech coding data compression algorithm that was first proposed by Fumitada Itakura of Nagoya University and Shuzo Saito of Nippon Telegraph and Telephone (NTT) in 1966. LPC was capable of speech compression down to 2.4 kbps, leading to the first successful real-time conversation over ARPANET in 1974, between Culler-Harrison Incorporated in Goleta, California, and MIT Lincoln Laboratory in Lexington, Massachusetts.[71] LPC has since been the most widely used speech coding method.[72] Code-excited linear prediction (CELP), a type of LPC algorithm, was developed by Manfred R. Schroeder and Bishnu S. Atal in 1985.[73] LPC algorithms remain an audio coding standard in modern VoIP technology.[71]

VoIP stands for Voice over Internet Protocol. It is also referred to as IP Telephony, Internet Telephony, and Internet Calling. It is an alternative way of making phone calls that can be very cheap or completely free. The ‘phone’ part is not always present anymore, as you can communicate without a telephone set. VoIP has been named the most successful technology of the last decade. 
Government and military organizations use various security measures to protect VoIP traffic, such as voice over secure IP (VoSIP), secure voice over IP (SVoIP), and secure voice over secure IP (SVoSIP).[39] The distinction lies in whether encryption is applied in the telephone endpoint or in the network.[40] Secure voice over secure IP may be implemented by encrypting the media with protocols such as SRTP and ZRTP. Secure voice over IP uses Type 1 encryption on a classified network, such as SIPRNet.[41][42][43][44] Public Secure VoIP is also available with free GNU software and in many popular commercial VoIP programs via libraries, such as ZRTP.[45]
Our real estate investment company has 14 phone lines altogether. For a phone service, we needed a local number, good call quality, uninterrupted service, calling apps for our laptops and cell phones, and an internal messaging platform for team communication. We started out with a niche company called Sound Communications, but their call quality and app were not very good. So once we made a bit more income, we decided to switch to RingCentral. RingCentral provides great call quality and is highly recommended in the real estate investment community. They are on the pricier side—$419.88 per line per year—but I’m OK with the price because their service is worth it and the high-quality phone calls are very important to our business.
Collective communication is the future of business communication. This type of communication technology enables users to communicate using a variety of data formats. For example, you could text your colleague about something you might have received in an email. Different data formats are combined to ensure that people who are contacted in a way are able to get the message in different ways. VoIP and unified communications go hand in hand.
The benefits of making the change permanently from a traditional landline phone to VoIP phone services can have a lasting effect — minimizing cost and maximizing customization. Turning your home into a fully integrated network, VoIP is the most economical and intelligent method of making phone calls. Doing away with your landlines means doing away with fees and long distance charges in favor of one low monthly rate. The sooner you do away with landline service, the sooner you’ll be enjoying more features for substantially less, saving hundreds of dollars a year. Make the switch, and leave those switchboards in the dust…you won’t regret it – Get VoIP!
VoIP (pronounced “Voyp”) stands for “Voice over Internet Protocol” and to make a long story short—it allows you to make calls through your home internet connection. When you make a call with your VoIP system, your voice is converted into data and transmitted to the caller at the other end in the form of high-quality audio. The sound and connection typically are seamless enough to where you won’t even know the call you’ve received is from a VoIP line. 
What makes SIP so popular is not only that it's deep and flexible, but also because it was purpose-built to engage in multimedia (meaning not just audio but also video and even text) communications over TCP/IP networks. For VoIP calls, SIP can set up calls using a number of IP-related protocols, including the Stream Control Transmission Protocol (SCTP), the Transmission Control Protocol (TCP), and the User Datagram Protocol (UDP), among others. But it can also handle other functions, including session setup (initiating a call at the target endpoint—the phone you're calling), presence management (giving an indicator of whether a user is "available," "away," etc.), location management (target registration), call monitoring, and more. Despite all that capability, SIP is simple compared to other VoIP protocols primarily because it's text-based and built on a simple request/response model that's similar in many ways to both HTTP and SMTP. Yet, it's still capable of handling the most complex operations of business-grade PBXes.  

By default, network routers handle traffic on a first-come, first-served basis. Fixed delays cannot be controlled as they are caused by the physical distance the packets travel. They are especially problematic when satellite circuits are involved because of the long distance to a geostationary satellite and back; delays of 400–600 ms are typical. Latency can be minimized by marking voice packets as being delay-sensitive with QoS methods such as DiffServ.[16]

The products and services in this review roundup are focused on business use and because of this either provide some PBX features or serve as full-on virtual PBXes. This may mean, among other things, that they provide service to telephone sets on your employees' desks. Most also support electronic faxing in some fashion, either directly (which can be a significant challenge for some VoIP services) or by simply integrating an incoming fax with your email system. Other popular features are video conferencing and shared meeting software (so meeting attendees not only hear each other but can present presentations or documents in a shared work space).
The following table provides a high level summary of how residential VoIP service compares to other alternative solutions for home phone service. The table compares this service to a regular landline, a bundled phone service from a cable company such as double or triple play, and a cell phone service. The cell phone is included as some people decide to just get rid of their wired phone and use their cell phone for all calls. Free services such as Skype are not included as they are not effective, like for like, landline replacements in our opinion.