The security concerns of VoIP telephone systems are similar to those of other Internet-connected devices. This means that hackers with knowledge of VoIP vulnerabilities can perform denial-of-service attacks, harvest customer data, record conversations, and compromise voicemail messages. Compromised VoIP user account or session credentials may enable an attacker to incur substantial charges from third-party services, such as long-distance or international calling.
Most of these VoIP solutions will require stable and consistent internet connectivity at every location where wired phones are to be used. At the very least, your business phone system must have access to a business class internet link to the cloud. This should be a dedicated link through a dedicated router if you expect your phone calls to sound as if they were coming from a business and not someone's home Skype connection. But it's important to know that you will also need a router that can create a virtual LAN (VLAN), and one that has the ability to encrypt voice traffic, and only your voice traffic. VoIP security from end to end for all calls is now a business necessity.
Using a separate virtual circuit identifier (VCI) for audio over IP has the potential to reduce latency on shared connections. ATM's potential for latency reduction is greatest on slow links, because worst-case latency decreases with increasing link speed. A full-size (1500 byte) Ethernet frame takes 94 ms to transmit at 128 kbit/s but only 8 ms at 1.5 Mbit/s. If this is the bottleneck link, this latency is probably small enough to ensure good VoIP performance without MTU reductions or multiple ATM VCs. The latest generations of DSL, VDSL and VDSL2, carry Ethernet without intermediate ATM/AAL5 layers, and they generally support IEEE 802.1p priority tagging so that VoIP can be queued ahead of less time-critical traffic.
^ Jump up to: a b Mahanagar Doorsanchar Bhawan and Jawahar Lal Nehru Marg (May 2008). "Telecom Regulatory Authority of India (TRAI) Consultation paper on Issues related to Internet Telephony. Consultation Paper No. 11/2008" (PDF). New Delhi India: Telecom Regulatory Authority of India (TRAI). p. 16 (Section 184.108.40.206 PC–to–Phone Internet telephony). Archived from the original (PDF) on October 6, 2014. Retrieved September 19, 2012. An end user is allowed to make PC–to-Phone Internet Telephony calls only on PSTN/PLMN abroad.
The SIP-T46S IP phone is the communications tool for busy executives and professionals. This business phone has a faster interface with a rich, high-resolution TFT color display. It’s built with Yealink Optima HD technology, and wideband codec enabling crystal clear communications. The SIP-T46S is also built with Gigabit Ethernet technology for rapid call handling and use with accessories like a Bluetooth USB Dongle and a WiFi USB Dongle.
The interest that VoIP technology is generating for consumers and businesses alike, is creating a high level of demand that is being addressed by more and more providers entering the market. Choosing the best home phone service can now be a challenge as it can be difficult to compare providers that have different pricing structures, different features and different contract terms. Many residential providers names are becoming familiar in the home, such as Vonage, MagicJack and Ooma. Vonage, one of the more expensive options today, is popular due to its unlimited international calling feature. Evaluating Vonage competitors can save you even more money depending on your exact needs.
An important disadvantage of the landline is that you cannot easily scale it up or down. This is why many companies with rapidly expanding or contracting business sizes prefer VoIP because it allows enterprise management to easily add, edit or even delete user rights centrally through the control panel. It is not necessary to follow the tedious processes involved if you are using a regular landline. This makes internet phone technology significantly more suitable for large business organizations.
A high speed Internet connection is required to "carry" your calls so if you have an Internet outage (or your ISP has an outage) then your phone service will not work. Internet services have improved significantly in the last few years and outages tend to be much less common than they use to be. Again, if you have a cell phone then this may not be an issue for you.