Telephones are a crucial part of modern living while at home, but taking them on the road when travelling can get expensive. Hotels often overcharge for trunk calls from room telephones, while mobile providers charge inflated "roaming" fees if calls made while abroad are billed through your home provider.
By contrast, a high-speed Internet connection can be used to make calls to landlines in most industrialised nations for a penny or two a minute; calls to other Internet telephony users on the same service are often free.
Where you have full access to the Internet at a reasonable speed and price, making phone calls over the Internet is the cheapest option. See Internet access for more detail on that part.
Free calls are possible if both parties have Internet access and are running the same or compatible software; many laptops, smartphones and tablets now include a small built-in camera (webcam) for video calls. Softphone clients for many webcam servers (such as Skype, FaceTime or Viber) are free to download or come included in your device.
Calls where one party is using a conventional telephone and the other is using an Internet connection (such as a Wi-Fi hotspot) are not free, but are far less expensive than conventional overseas telephony. A call to a landline anywhere from London to Los Angeles from the broadband Internet can cost as little as a penny a minute, as the voice service provider (VSP) doesn't have to transport the call to those faraway places – the Internet already does that. The VSP merely finds a least-expensive gateway to convert the call back to landline telephony at destination.
When carrying a portable device (laptop, smartphone or tablet) to a location which provides access to a Wi-Fi hotspot, access to inexpensive Internet telephony merely requires installation of (usually free) software and signup to a voice service provider (VSP). Be sure to test your configuration before departing.
A headset will give better sound quality than the built-in speakers if using a PC or tablet; smaller devices (iPhone, iPod Touch, Blackberry, Android handset) are suited directly for use as telephone handsets, giving the look and feel of mobile telephony with no need for any external hardware. The quality of the actual telephone calls, in any case, will remain at the mercy of the underlying Internet connection. If connection speed is sporadic and unreliable, the audio will contain annoying dropouts; if the connection is consistently fast (both outbound and inbound) an Internet telephone will work well.
Some PC applications suppose you have a good connection and by default use a codec (coder-decoder) which optimizes voice quality at the expense of bandwidth. With a codec optimized for compression, a data rate well under the 56 kbps of a landline connection may suffice; without compression, one voice call plus packet overhead uses about 80kbps and needs this data rate consistently. For some connections you may want to allow much more lag than the default, as delayed packets will otherwise be discarded.
In some destinations, one may rent a computer with Skype from a local Internet store.
There are various platforms for transmitting voice (and, in some cases, video) over the Internet:
SIP is a standard used by many small Internet telephone companies; it's useful as a replacement for conventional telephony. Computer retailers offer hardware which uses this session initiation protocol to connect a standard desk telephone to a virtual Internet phone line; there are also mobile apps (softphones) which let you take this Internet home phone with you on your travels. Someone rings your home phone, you seamlessly take the call at a wi-fi hotspot half a world away.
Proprietary webcam apps are useful primarily for communicating with other users of the same app; this has the advantage of incurring no charges per call and often allows transmission of both voice and video. Apple's Facetime and Microsoft's Skype fall into this category, along with a few other "messenger" apps. Calls to regular mobile and landline numbers are not always supported and, where available, may cost more than the same call on a generic SIP provider.
A VoIP connection behaves poorly if used as a virtual "telephone line" to operate dial-up modems. Internet packets are prone to often be dropped, delayed or delivered out-of-sequence during a call; this might go unnoticed for a voice call, but will cause errors and disconnections that render the connection unusable for fax or data.
The usual workaround is to employ a fax-to-Internet gateway at the upstream provider. An inbound fax is converted to a PDF file the moment it arrives from the public switched telephone network and e-mailed or made available for web download; an outbound fax is uploaded in a similar manner.
In theory, another option is T.38, a standard in which an analogue telephone adapter demodulates the fax tones, extracts the original digital data and sends that. In practice, most upstream providers don't support T.38 and new laptop or portable computers haven't included FAX-capable built-in dialup modems for a decade or more.
Eventually, the business community will acknowledge that a fax (a low-quality computer-scanned image sent on a slow dial-up modem) is no more a "reliable original document" than the same piece of paper scanned to PDF and attached to a standard e-mail message. In the meantime, just hand out the "special fax number" issued by your VoIP provider's gateway and no one need know these missives merely land in the same "in" box as the rest of the e-mail and the spam.
VoIP is often insecure
<p>Do not assume that calls made this way (or, for that matter, with a phone) are private.</p><p>Security experts believe that at least the US, China and Russia can tap Skype calls, other VoIP systems are also vulnerable, and there is little reason to suppose that those governments are the only possible eavesdroppers.</p><p>If you need security against serious attackers, either check the security of your VoIP configuration with the help of a trusted up-to-date security professional, or use encrypted email instead. Commonly used protocols using strong encryption have been found vulnerable to statistical attacks. And regardless, make sure you prevent breaking into your device, to the best of your abilities.</p>Some publicly available networks can block VOIP, many are simply too slow, and in some countries, Internet telephony is blocked entirely to protect overpriced national phone monopolies. Public hotspots vary widely in quality; some may provide access to the full Internet, others might provide access to just the Web (which is one Internet application among many) or a limited number of services while blocking everything else. Some may only enable a connection after a user opens a webpage and "agrees" to a long list of incomprehensible conditions and legalese. These issues are independent of the speed of the underlying connection.
VOIP is a good way to maintain contact with friends and family while travelling, who will tolerate the occasional drop-out. It may not be the best way to maintain a connection with important business contacts.
Etisalat, the state-owned telecommunications provider of the United Arab Emirates blocks access to the Skype network entirely. However, Skype is still accessible from some hotels that provide access through 'TheWayOut' Wi-Fi service.
Some providers may block calls placed from IP addresses in various foreign lands, if those foreign countries are a source of fraudulent Internet telephone calls or abnormal patterns of usage. A few providers block calls to certain high-priced destinations, unless they receive a verifiable request from the subscriber to unlock them. The same approach to flagging unusual usage patterns occurs with other on-line services (so repeated attempts to log in from Moscow to a Google account which belongs to a North American user might be flagged as questionable); check with your provider before departure.
A virtual private network (VPN) will allow you to connect to your own home-country office and circumvent many of these issues (you can even appear to still be at your desk when you're actually travelling the world on business), although a few particularly dictatorial nations will deny you access to a VPN.
There are various ways to get on-line to make inexpensive voice calls; these fall into two main categories:
Various devices are promoted for home or office use:
While certainly capable of providing the functionality of a standard desk telephone, in many cases without the need for a computer, these are intended for fixed installation (such as home or office) as they are awkward to carry.
There are various free applications (SipDroid, Vimphone, CSipSimple) which can be used to make telephone calls from Android-based smartphones. As these use the handset's wi-fi connection, there is no need for a cellular/mobile telephone subscription. With these apps, a SIP provider is needed to reach standard telephones; costs start at $0.85 USD/month (per DID number) $0.009 USD/minute (incoming calls, based on voip.ms).
As with PC's, there are instant messenger applications which can communicate with other Internet users on the same service for free.
As prepaid mobile vendors are flooding the market with under-$100 Android devices, the costly single-purpose "cordless wi-fi Internet phone" handsets are becoming rare. It's actually cheaper to buy the general-purpose Android and install a free app to use it as a cordless VoIP phone.
The form factor of a typical Android, Blackberry smartphone or iPod looks and feels like a telephone handset, making the platforms ideal for running Internet calls over wi-fi. No need for a separate microphone and headset, the whole package is one inexpensive pocket-sized device which typically also provides an e-mail client, camera, media player and travel alarm clock.
Capabilities of iPhone/iPod apps are similar to those of Android devices, although specific applications to make SIP calls will vary (Acrobits, Fring, Linphone, Media5-fone, NetDial Sip Phone and Zoiper all exist on both platforms). It is possible to make calls from the iPod Touch, which is not a telephone but which supports wi-fi and has a front camera for webcam-style instant messenger calls. Apple's proprietary messenger, FaceTime, is supported on iPod and iPhone.
Most of the standard instant messenger and webcam applications (such as Google Voice, Yahoo or Skype) originated on PC's, although some now also have iOS or Android versions. When using a tablet, laptop or PC it may be desirable to add a wired headset or a wireless Bluetooth headset; the audio otherwise will be speakerphone quality at best.
Various SIP-compatible softphones (such as Ekiga) may be used to call from a computer to the telephone network through a SIP provider. Some messenger apps can be used to call telephones for a fee, which is usually higher than the cheapest unbundled SIP voice-over-IP services.
While you may have an internet telephony app for your smartphone, your mobile phone provider might also offer to make your normal calls go over the internet. Enabling the feature is a simple configuration switch on most modern phones, but the company might still charge as for normal calls. With the right plan, and a cheap or included data connection, this is probably cheaper than normal roaming international calls, and certainly handier than setting up a separate service, but not the free calls you'd get with normal internet telephony via a free Wi-Fi hotspot.
Because calls are routed over the Internet, you do not need to use a phone company located where you live or where you travel. There is also no requirement that you obtain a local number from the community in which you live; you can obtain a satellite Internet connection in the wilds of Chicken, Alaska and select a number which claims you're in sunny Arizona. Often, you have to buy a global number separately that allows PSTN phones to call you. Where the number is from makes a difference for people calling you.
There are literally thousands of VOIP companies. It is best to pick a company which has connections either in the country you are calling from or calling to, to avoid unnecessary international hops.
Many (but not all) of these providers will allow free calls over the Internet to other subscribers on the same server, as these internal calls never reach the public switched telephone network (PSTN).
These websites call you on your homeline and the person you want to call, using normal phones.
Direct inward system access (DISA) is a feature deployed by some Asterisk PBX-based providers, such as Swiftvox (voip.ms). It functions much like a calling card service; dial your own number using a normal phone, enter a code, then get a dial tone from your voice-over-IP provider's private branch exchange to call back out inexpensively using Internet telephony. It's more expensive than calling with a softphone app from a wi-fi hotspot (as this incurs the cost of both an inbound and an outbound call) but can be a viable alternative to purchasing prepaid calling cards.
A similar concept is a "calling card number" provided by a voice-over-IP carrier as part of the same package (or on the same bill) as Internet telephone service. These can allow travellers to avoid the short expiry dates and many hidden fees on prepaid cards in local convenience stores, but be sure to check that you (or your carrier) have a local access number in the places you plan to visit.
Yahoo Messenger (YM) allows users of selected countries to call any phone after topping-up (via credit card) starting at $10.00. As with Skype-to-Skype calls, YM calls to another active YM user on the Internet are free of charge.
Google Voice may be used to make inexpensive calls and can provide a local number in the United States of America.
Apple's FaceTime allows free video calls between users of MacBook, iPhone or iPad devices; the software is pre-installed on the latest versions of the iPhone and iPad. Unlike Skype's video calling, FaceTime is not available for non-Apple devices (such as Androids or Windows/Linux PC's).
Some Internet phone companies like Musimi will forward voicemail messages as email attachments so you can listen to them at Internet cafés when travelling. This is also part of the package at some of the VoIP carriers (along with the standard options to forward to a regular telephone number or an Internet device).
Related: List of country calling codes