Communication on the internet takes place through an exchange of  "packets". In a communication between two users, the network does not reserve a channel for their exclusive use, but does what it can to ensure the correct reception of the packet (hence the acronym which defines the internet as a best-effort type). The internet proves to be more efficient than traditional telephone circuits in terms of the amount of network use that can be obtained. Conversely, however, it can suffer from problems of congestion and delay in delivery of the packets, which does not happen with traditional circuit networks. Regarding rates, because the network does what it can to deliver information, internet tariff policies consist in charging a lump-sum for access to the network. In essence, you pay for network access and not for the quantity of traffic (connections by means of traditional lines means, for example, internet connections through 54K modems). The other difference, in respect to traditional lines, lies in the fact that the cost does not depend on the distance between the terminals. What you pay your provider for is access to the network. Once you are connected to the network, you can make unlimited calls to other internet users around the world. When it becomes necessary to make a call from a PC to a conventional telephone user, at some stage the boundary between the internet and the telephone network will have to be crossed in order to get through. This requires a connection point between the two networks (a Dial-out Gateway). The provider offering this type of service must bear the telephone costs that will be charged to the user making the VoIP calls. The charges for this type of service are quite affordable: this is because internet phonecall providers try to have a large number gateways spread across the territory in order to be as close as possible to most of the possible destinations. In this way the distance to be covered by the fee-charging telephone network is as short as possible. For example, a VoIP call to a district of Singapore (with a local carrier) is composed of an international stretch (as far as Singapore, for example) which is free, because it is provided via internet, plus a distance over which a fee is charged, because it is served by the telephone network. The total cost, then, is equal to the cost of the local internet connection plus the cost of a local call (that is to say, at the Singapore telephone rate). So at that point it can be understood that technology could trigger a real storm in the telephone company business. If the use of VoIP technology were to become commonplace (as is happening in recent times) and all users had a "flat" type internet connection, in a very short period a dramatic fall in the earnings of "traditional" telephone companies would be seen. The spread of VoIP technology will displace analogue telephone technology, and since it is only a matter of "when", and not "if" it will happen, telephone companies are waging a defensive campaign based on the increase of connection costs and the reduction of the cost of calls.