The Essential Guide to VoIP Security

The Essential Guide to VoIP Security

The Essential Guide to VoIP Security

It's a well-known fact that VoIP technology sends voice data over networks through data packets. Data-networking technology allows top VoIP providers to provide an array of powerful and flexible call-management options at a rock-bottom cost.

The downside to VoIP's data-focused structure is that it exposes voice-over IP programs to many of the same threats that imperil enterprise data networks and computers — and sometimes extends their range, making them more difficult to detect. Many observers believe these security threats represent the biggest challenge VoIP adopters face.

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VoIP threats come in many forms, including:

  • DDoS (distributed denial of service) Attacks: Although largely viewed as a website threat, DDoS attacks can also be used to take down a VoIP system and VoIP phone services. By flooding a network with useless data — including automatically generated spam calls — attackers attempt to ensure that VoIP calls can't get through or proceed only in a delayed and degraded fashion.
  • Snooping: Since some VoIP calls move over the open Internet, they are vulnerable to snooping at various points during their journey. An attacker with network access and a packet-sniffing program downloaded from the Web can monitor and record calls relatively easily. Even inside an enterprise that uses a private backbone, the same sniffing technologies can present a threat.
  • SPIT (SPam over Internet Telephone): SPIT is still a largely theoretical threat, but it has the potential to be just as distracting and resource-draining as its email equivalent. Only a handful of SPIT outbreaks have been reported to date, but "legitimate," automatically generated political and credit-card calls are already pushing the limits of acceptability.
  • Vishing: The VoIP counterpart to email phishing, vishing attackers target the phone numbers of VoIP users and attempt to lure them into bogus moneymaking schemes or trick them into disclosing credit card numbers and other vital information. Like SPIT, vishing is not a widespread issue but a growing problem.
  • Direct Hacks: Like data networks, VoIP software is also vulnerable to direct hacks via unsecured "holes" in the system. Fortunately, also like data networks, groups are watching for these vulnerabilities and pushing fixes out as soon as possible.

These are usually system-specific problems, so, for example, a new release of Asterisk, the open-source IP PBX platform, might display vulnerability. Typically, a fix is announced within a couple of days of the vulnerability's discovery.
Security Approaches

Dealing with VoIP threats is a constant, never-ending chore. Since attackers are always devising new ways of breaching VoIP safeguards, it's important that businesses keep on top of the latest threats and adopt fresh measures to counter evolving attacker strategies.

Most security experts recommend that VoIP safeguards be blended with the measures that are used to protect a company's existing data network, creating a comprehensive security environment. Common security techniques (which apply to data networks as well as VoIP networks) include:

  • Firewall: A firewall is designed to allow or block data flowing into or out of a network. Firewalls are available as stand-alone hardware appliances or as software (typically installed inside a router or a gateway). A firewall can provide services such as stateful inspection (analyzing transactions to ensure that inbound packets were requested) and packet filtering (blocking data from specified IP addresses and ports).
  • IDS (Intrusion Detection System): An IDS analyzes incoming data traffic for suspicious types of activity. If it detects something peculiar, the IDS alerts the network administrator, who can then move to halt whatever event (such as a DDoS onslaught) is taking place. A variety of vendors offer IDS solutions with all sorts of capabilities, allowing businesses to find a product that most closely matches their requirements for VoIP security.
  • IPS (Intrusion Prevention System): An IPS is similar to an IDS, except that the product is designed to take immediate action — such as blocking a specific IP address or user — rather than simply issuing an alert. Some IPS products also use behavioral analysis to spot and stop potentially dangerous data.
  • DDoS Protection: Specific anti-DDoS products from vendors such as Cisco Systems Inc. and Symantec Corp. can quickly detect the start of an attack, filtering out bogus service requests so that legitimate ones can pass through unimpeded.
  • VPN (a virtual private network): Placing the VoIP infrastructure on its own encrypted VPN "island" can isolate the system from external attacks.

Specific techniques for voice over IP VoIP software security usually focus on the human side of the equation and include:

  • SPIT and Vishing Education: Many enterprises take it upon themselves to educate employees and other VoIP system users about SPIT and vishing attacks, as well as to be alert to signs that someone may be trying to tap into the business's phone system.

Fundamentally, there is no difference between VoIP security and the normal security requirements associated with any well-protected data network. In nearly all respects, VoIP, Web, and email protection are simply different aspects of a single security issue.

How to choose the best VoIP provider?

This is obvious that VoIP is the best IP Phone service you can choose for your business. Still, choosing the right VoIP software and VoIP provider is not always as easy as it appears. This guide will help you choose the best among the largest VoIP providers. 

How to choose the right VoIP vendor?

The VoIP world is emerging and getting big and big every day. With hundreds of VoIP carriers to choose from, it's no surprise that some people find it challenging to find a company they would like to work with. Don't settle for a VoIP provider; find one that meets your requirements and offers the best VoIP services. You can use the following tips to pick the right one among the best VoIP providers.

  1. Know the VoIP phone services you want
    You must know what voice-over IP VoIP software features are essential for your business and how much you can pay for them a month. Common VoIP services are Caller ID, Call waiting, 3-way calling, and voicemail.

    Some top VoIP companies offer a free second line with a subscription and advanced features, for example, enhanced voicemail. If you have a business requirement for making international calls, consider a business plan offering free minutes to the countries where you have to make most of the calls. 

  2. Search for the popular VoIP phone providers
    Once you know the features and pricing plans, start searching for the VoIP companies that offer secure VoIP software.

  3. Read reviews and check ratings
    When you choose a VoIP vendor, read its voice-over IP service review. Pay attention to other details such as sound quality, service reliability, and customer service.

  4. Read the terms and conditions for the VoIP vendor
    If you're happy with the price, plans, features, and customer reviews of the VoIP vendor you chose, go to their website and read their voice-over iPhone systems reviews and terms and conditions. Read FAQs. You can also ask them questions if you are still unclear about something.

Voice-over IP comparison helps you choose the best among all the existing VoIP vendors. There are plenty of great options on the market; choose the one that's best for your business phone system for cost-effective and efficient business communications.

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