You must have asked yourself what the 'IP' in VoIP means? IP stands for 'Internet Protocol'; but again, what is the 'Internet Protocol' and what is it good for? This piece of writing will help curious minds understand how voice can be transmitted over IP, thereby making them appreciate how IP actually works. In it, we see
- The protocol
- Voice and IP
- IP Packets
- IP Addresses
IP is a protocol. Simply said, a protocol is a set of rules governing how things work in a certain technology, so that there is some kind of standardization. When put into a network communication context, a protocol is the set of rules governing how packets are transmitted over a network. When you have a protocol, you are sure that all machines one a network (or in the world, when it comes to the Internet), however different they might be, speak the 'same language' and can integrate into the whole framework. IP is probably the most common protocol over the Internet. It is the set of rules governing how packets are transmitted over the Internet.
The IP protocol standardizes the way machines over the Internet or any IP network forward or route their packets based on their IP addresses.
Along with addressing, routing is one of the main functions of the IP protocol. Routing consists of forwarding IP packets from source to destination machines over a network, based on their IP addresses.
When Voice Meets IP
VoIP takes advantage of this ubiquitous carrier technology to disseminate voice data packets to and from machines.
IP is actually where VoIP draws its power from: the power to make things cheaper and so flexible; by making optimal use of an already-existing data carrier.
When TCP couples with IP, you get the Internet highway traffic controller. TCP and IP work together to transmit data over the Internet, but at different levels.
Since IP does not guarantee reliable packet delivery over a network, TCP takes the charge of making the connection reliable.
TCP is the protocol that ensures reliability in a transmission, that which ensures that there is no loss of packets, that the packets are in the right order, that the delay is to an acceptable level, and that there is no duplication of packets. All this is to ensure that the data received is consistent, in order, complete and smooth (so that you don't hear a broken speech).
During data transmission, TCP works just before IP. TCP bundles data into TCP packets before sending these to IP, which in turn encapsulates these into IP packets.
An IP Packet is a packet of data which carries a data load and an IP header. Any piece of data (in the case of a TCP/IP network - TCP packets) is broken into bits and placed into these packets and transmitted over the network. Once the packets reach destination, they are reassembled into the original data. Read more on the structure of an IP packet here.
This is maybe the most interesting and mysterious part of IP for most of computer users. An IP address is a unique address identifiying a machine (which can be a computer, a server, an electronic device, a router, a phone etc.) on a network, thus serving for routing and forwarding IP packets from source to destination. Read more on these digits and dots that make up an IP address.