Thursday, August 13, 2015

Understanding TDoS Attacks On Your VoIP Telephony System

Surprisingly, one of the most disruptive techniques of compromising your brand-new VOIP telephony system has been around for years. Nonetheless, it is still very hard to fight and prevent. We are talking about the Denial of Service attacks of course, or their more telephony-specific variety called Telephony Denial of Service attacks (TDoS).

What are TDoS attacks?

TDoS attacks are similar to regular DoS attacks besides the fact that they target your phone numbers rather than websites. In case of a TDoS attack, you will receive a huge number of inbound calls that will make your system go out of order for some time and thus impede your communication abilities. The Internet connection makes is easier to generate calls and harder to block them, as new technologies are being developed to send calls from different cities and with different caller IDs. In fact, there are companies that offer this kind of “service” for a fee of only $50 or so.

The purpose of a TDoS attack is, of course, money. Usually, the flow of calls wouldn’t stop until a certain amount is paid to the perpetrators. To make the scheme even more fast working, they started targeting establishments that rely heavily on their communication systems such as hospital emergency rooms.

Reasons why the number of TDoS attacks is growing

Mark Collier, the CTO of SecureLogix Coreporation, gave three main reasons why TDoS attacks are getting more popular among swindlers:
  1. Technology advancements. Free PBX software and the use of SIP trunks for unauthorized purposes make it much easier and convenient to organize attacks.
  2. Clear motivation such as disruption of business, financial fraud, etc.
  3. The use of cheap resources – even free social networks can be used to organize TDoS attacks (e.g. there have been cases recorded when a tweet or a Facebook post called on users to start calling a particular organization at a certain time).

Types of TDoS attacks

As the technology advances, so do the TDoS attacks. Its most basic form – manual – is already a thing of the past and has given place to more complicated ones. Now is the time for automated and distributed automated attacks. In case of the former, calls are generated automatically and the number of the imaginary caller is changed every time. Yet they still originate from a single place. When a distributed automated attack is arranged, calls originate from different places (e.g. from different SIP trunk providers), there might be a different audio played every time a person picks up, and the caller ID changes every time. The last type is the most dangerous of all, as it makes it so much harder to identify the place of call origination and block it.

There is also another classification for TDoS attacks, which divides them into signaling, media and physical ones. In case of a signaling TDoS attack, the perpetrators target the signaling protocol. For example, they can create a vast number of call setup requests that use the entire capacity of the terminal or cancel pending call set up signals to make it impossible to end the call.

In case of a media TDoS attack, media-processing components of your VOIP system are flooded with a large number of RTP packets. Finally, physical TDoS attacks include forced power outage and physical damage to hardware.

Preventing TDoS attacks

To reduce the chances of your VOIP telephony system falling a victim of a TDoS attack, please follow the security tips we’ve provided here and here. To fight media and signaling attacks, implement strong authentication protocols. All components of your system should “know” they’re “communicating” with legitimate counterparts. A VOIP firewall is also an effective countermeasure, used to monitor abnormal activity within the system.

To avoid physical attacks, implement a system of limited access to key VOIP components and provide a backup power generation system.

As TDoS attacks have been recognized as a threat on a state level, FBI recommends to report all cases of such, preferably with all possible data gathered in the course of the attack – caller IDs, IP addresses, start and end times, etc.

Although associated with some risks, a VOIP telephony system is still an effective communication solution to boost productivity and reduce costs. With certain precautions, you can avoid the danger and gain the most of this cutting-edge communication solution.

Find out more about its advantages for small businesses and large corporations at

Thursday, July 30, 2015

Understanding Jitter and Packet Loss and How They Can Impact The Call Quality Of Your VoIP Telephony System

Keeping up with our best practices, today we’re offering you more insight into successful implementation and use of your VoIP telephony system, regardless of which communication solution of you are using (direct inward dialing numbers, short duration termination, etc.). 

Some of the most frequent VoIP quality issues involve what are known as jitter and packet loss. We will discuss what a jitter is, how it can affect your call quality, as well as what factors might cause this connection problem.

So, what is jitter?
From a user’s side, jitter means unstable voice flow in a telephone conversation, i. e. the situation when parts of the conversation are delivered with a delay or not delivered at all. In some cases, their order might be reversed, too, causing confusion and misunderstanding on both ends.

From the technical point of view, jitter occurs when voice data packets do not arrive in a steady flow, required by codecs for sustainable playback. Usually, packets are sent from a caller at the same time intervals, imitating the landline connection, but they do not always arrive in the same order or following the same interval pattern. 

In order to avoid any perceivable interruptions in a conversation, the jitter should be 20 milliseconds or less. As it increases, the connection quality drops. Especially high jitter rates will lead to packet loss (that is, when packets are not delivered at all and thus parts of the conversation are missing).
Packet loss occurs either randomly and only by single packets (called “gaps”) or in large numbers at once (called “bursts”).

What are the causes of jitter?
There are three main causes of connection jitter:

       1.  Wrong application of queuing. Inappropriate storage of voice packets and the wrong order of their transmission can lead to delays.

       2.  Misconfiguration. Faulty configuration of a router or a PVC might easily impede connection quality and cause a jitter.

       3.  Network congestion, which might cause irregular spacing between packets.

How to prevent or fix jitter?
In order to reduce jitter and ensure higher quality of connection, networks use jitter buffers – devices that collect packets from the caller and send them to the receiving codec in the right sequence and at even time intervals. In case of packet loss, jitter buffers duplicate missing data or adds comfort white noise.

However, a jitter buffer is not a universal decision. An increase of the buffer length can help reduce stronger jitter, but it will simultaneously lead to delays in voice delivery. If a longer jitter buffer causes a 300ms delay, it will make a regular phone conversation much more difficult.

Besides using a jitter buffer, companies can examine their networks in order to see what causes the jitter and then either correct the instances of wrong configuration or allocate more bandwidth or use Priority or Law Latency Queuing.

Understanding the causes and the impacts of jitter will help you get the most of your VoIP technology provided by See what VoIP solutions we offer and rest assured that no matter which solution you choose, you will receive continuous troubleshooting and maintenance assistance.

Stay tuned for more information about VoIP termination and origination services, appropriate solutions for small businesses, and useful security tips. 

Wednesday, July 15, 2015

Preventing Toll Fraud When Using SIP Trunking Services

We hope you have already embraced all the benefits of SIP trunking and are using it to increase the efficiency of your business communications. We also hope that you stick to security protection measures described in this blog post. Today, we’d like to look deeper into one of the threats looming over the effectiveness of your telephony system, namely toll fraud.

It’s hardly a new invention and it has plagued legacy telephone systems for years. In the traditional scheme, a person gets unauthorized access to someone else’s phone line to make long-distance calls and avoid paying for them. With the transition to cloud-based technologies and low-cost communication, it has become less profitable and more complicated, but the problem still exists. 

There are several vulnerable points that provide opportunities for unauthorized access. These are:

- Configuration errors and technology malfunctions

- Flaws at the level of technology application by users (authentication, passwords)

- No protection on devices, especially mobile ones

- Connectivity of the PSTN (accepting calls from virtually anyone)

Good news is – there are specific measures that can help you protect your telephone system from fraudulent activity and avoid paying someone else’s bills, including your own sticky-fingered employees. Some of them fall in the general protection category, while others deal with toll fraud specifically. Add them to your regular security practices and double-protect your system.

1. It has already been said – and we can’t stress it enough – that all users having access to your telephone system should change default passwords and use their own high-security ones, which should be changed on a regular basis.

2. Most of the fraudulent activity happens when no one is there to track it down. That’s why a smart move would be to restrict calling before and after business hours.

3. If there is any unused equipment – such as modems – physically disconnect them.

4. Monitor call patterns on a regular basis. Plenty of fraudulent activity might take place within a short period of time, and without regular audits, you risk missing it.

5. Restrict transferring and forwarding calls to external phone numbers. If possible, allow international calls only to pre-defined numbers and set a password for those who want to make them.

6. As soon as employees leave your company, delete their mailboxes and withdraw their access rights. This way you will not only prevent tampering with your system on the part of former workers, but also seal a potential security hole.

7. Do not accept any traffic that doesn’t come from your SIP provider – block other sources.

8. Use systems for intrusion detection and prevention firewalls.

9. Implement a system of tracking and signaling invalid access attempts.

10. Encrypt your SIP traffic with TLS (used for signaling encryption and authentication) or RTP (used for media encryption).

11.Update your system on a regular basis.

The VoIP experience can and will be rewarding – provided you implement it properly and remove all possible threats before they even emerge. Stay tuned for more useful information about SIP trunking, VoIP management, wholesale VoIP origination solutions and much more!  

Wednesday, July 8, 2015

The Benefits Of SIP Trunking Over PRI

What are PRI and SIP trunking? How are they different? Which one can offer more benefits for your business? In this post, we will try to answer all of these questions and help you make the right choice.

What are these two services?
If we put it simply, PRI and SIP trunking are two ways of connecting your business to a Public Switched Telephone Network (PSTN) via a Private Branch Exchange (PBX). While PRI represents a physical connection, SIP trunking is a virtual one, which is applied on top of the existing data connection network within your organization.

What is SIP trunking exactly?
SIP trunking (also referred to as VoIP termination) is a VoIP service that allows you to send calls through a carrier’s network. The letters stand for Session Initiation Protocol and represent a packet-switched technology. The latter means that small units of data – packets – are sent through the network and do not prevent other packets from entering the channel at the same time. Most Internet traffic is sent using packet-switched technology.

What is PRI?
PRI, or Primary Rate Interface, is a physical connection between your business and the PSTN. PRI is a circuit-switched technology, which means that a physical path is reserved for the entire duration of a certain connection between two end points and no other data can be sent along this path while it is in use.

What are the main differences for businesses?
PRI is a physical telephone line (T1 with 23 channels or E1 with 32 channels), which enables you to have 23 or 32 simultaneous calls respectively. Even if you use 100 phone numbers within your company, your employees will be able to have only a pre-defined number of connections at the same time. If your call volume is larger and you face the need to increase the capacity, you will have to purchase an additional phone line with 23 or 32 more channels. Ironically, even if you need only 1 channel more, it will still require an entire new line.

The use of PRIs is related to high costs – they’re charged per circuit on a monthly basis. Installation of every line takes 2 to 3 weeks and requires special (and quite expensive!) termination equipment, such as a PRI interface card, to be plugged into your telephony system. While the line is not in use, it cannot be applied for other purposes. Moreover, it is capable of carrying only voice data.

SIP trunking on the other hand is a versatile technology that can be aligned with your specific business needs. Its capacity depends only on the amount of bandwidth available and can be extended to accommodate an unlimited number of connections. Extra capacity can be easily purchased by phone and will take only a couple of hours to set up.

Unlike PRIs, SIP trunks are not stagnant: when they’re not used, the corresponding bandwidth can be applied for other purposes.

The winner of the competition is obvious, don’t you think? While PRIs have their benefits such as a guaranteed call quality, they’re a thing of the past now. The world is switching to virtual services to reduce costs and increase communication efficiency. If you too want to boost the competitive edge of your business, it’s time to take a closer look at our wholesale SIP trunking services. They might just save you thousands of dollars! 

Wednesday, July 1, 2015

Vanity Phone Numbers: Explore Their Marketing Potential

Is your company already benefiting from a toll-free number? Don’t worry, we are not going to recite the perks all over again. If you have been following our blog or have done a little research, you already have a solid list of reasons to use toll-free origination

Today, we’d like to go a bit deeper into specifics and discuss how certain telephony practices can provide a boost for your business not only concerning cost reduction, but also marketing and sales.

If you recall, we’ve previously talked about using a local phone number to seem more accessible to customers; as well as purchasing a toll-free number to come across as an international brand. The next stage is integrating your telephony system into your marketing campaign, and this is where a vanity phone number could come in handy.

What is a vanity phone number?
A vanity phone number (also called a ‘toll-free phoneword’) is a number that incorporates a toll-free prefix (in most cases 1-800) and a few words or an acronym (e.g. 1-800-FLOWERS). Vanity numbers have been in use for a couple of decades already, but with the emergence of the Internet and the development of various advertising channels, these numbers have enjoyed an increase in popularity. 

Why do businesses buy vanity phone numbers?
To provide you with an objective evaluation of the effectiveness of vanity phone numbers, we will name the pros and cons of getting one for your business.

You should get a vanity phone number because:

It is much easier to remember and recollect. Here are a few numbers from a corresponding study: the results proved vanity numbers had a 75.4% higher recall rate than numeric numbers, and 57.6% higher than URLs. The results differed only slightly depending on the age group and media formats (audio and visual). Even if we neglect the science for a moment, which is easier for you to remember: 1-800-NEW-TIRES or 1-800-639-84737?

A vanity phone number helps your business (even if it is rather small) to look like a big corporation with international coverage. Survey subjects mentioned that a vanity number made businesses look more professional. While the 1-800 prefix is associated with considerable business scale, the “vanity part” of it proves that a company invested in its communication strategy.

A vanity phone number provides excellent opportunities for brand building. If you complement it with the corresponding domain name (e.g., you will automatically enhance its advertising effect. Plus, if the lexical part is associated with your product (e.g. 1-800-FLOWERS), the number will speak for itself. As for advertising campaigns, vanity phone numbers generate 25-50% more response.  In audio advertisements, where capturing a telephone number in the word flow is even more difficult, the addition of a vanity number can lead to a 60% increase in response.

You should use some caution because:

You vest your hopes in technology, which may betray expectations – not all phones now have the means to dial vanity numbers. Also, it is easier to dial numbers than letters, especially if you choose words with difficult spelling (my friendly advice – don’t chose a complicated name).

A vanity number will complicate local search optimization, as it will be more difficult for search engines to associate your business with a certain location.

As usual, the right solution is somewhere in between. If you are not ready to transfer to a vanity phone number, why not use it as an additional marketing tool? After all, the advantages are numerous and outweigh the associated costs.

Ready to make a step forward and order a complete package of VoIP services? Click here to sign up and enjoy all the benefits it can offer.

Need more information? Find out everything about VoIP termination and origination, as well as short-duration termination services at 

Wednesday, June 24, 2015

What Is VoIP Redundancy And Why Is It Important For Successful VoIP Implementation?

With all the benefits that VoIP origination offers to small businesses and big international companies, there is still a vulnerable spot that makes many customers doubt whether the game is worth the candles. This is of course, the Internet connection. We’ve already talked about securing enough bandwidth and checking if there are any weak spots BEFORE implementing the new telephony system. However, there are things that you simply cannot control, like natural disasters or other force majeure circumstances, which will disrupt your Internet connection. It will lead to breaks in communication as well, which translates to lost opportunities and inability to talk to clients and partners.

There is no chance to control nature, but there is definitely a chance to reduce the dependency of your telephony system on the ISP. This is what we call Internet redundancy.

So, what is redundancy?

Imagine that you are going on a picnic and find out that the road is blocked. Instead of waiting until the way is cleared, you simply switch your route. A similar process occurs in your data network if the VoIP redundancy principle is complied with: the data simply travels an alternative route, thus, your communications do not suffer.

How to arrange Internet connection redundancy for VoIP?

The answer is quite simple – you need two Internet service providers. Many businesses are already using this approach, knowing that they can’t afford any connection downtime. The distribution of services between those two ISPs can be different. Some choose to assign different functions to them, and if one fails, its functions are automatically transferred to the other. Another scheme is to use one of the ISPs for backup purposes, i. e. most of the time it is non-active and used only in case of emergency.

Of course, using the services of two ISPs will be more expensive. This is why you have to evaluate reliability of your main provider and the costs your company incurs in cases of interruption in its services before making a well-informed decision on engaging another ISP. In most events, however, arranging Internet redundancy in this way pays off.

Another way to boost reliability, which is often overlooked, is to increase the number of connections between your telephony system and the Internet infrastructure.  In this case, if one Internet cable is damaged, the remaining connections will serve to maintain your communications.
In essence, redundancy is about providing a backup plan for everything. We ensure redundancy of our telecommunication services, but alas, there are still some efforts required on your part to ensure uninterrupted functioning of your VoIP telephony system.

Just like any other cutting-edge technology, VoIP requires a complex approach to work at its highest efficiency, and Internet connection redundancy is its major component.

If you’d like to learn more about how a strong VoIP termination package with superb global coverage and redundancy can help your business, visit