Sometimes with all the different terminology and acronyms, things can get a little confusing. Hopefully this page may shine some light on what terms are used throughout this site.
POE - Power over Ethernet: The ethernet switches supply power in order to drive certain devices without the need for an external power supply.
VOIP - Voice over IP: The ability to send voice traffic over data networks without the need for a separately wired network, usually 2 or 4 pair copper cable wired directly to the phone system.
QOS - Quality of Service: The ability to prioritize certain types of data across your LAN / WAN
VLAN - Virtual LAN: The ability to separate networks within the same ethernet switch, allowing data to be isolated from each other and having their own QOS attributes applied. VLANs are essential in Voice over IP to ensure that normal day-to-day data traffic does not interfere with the high priority voice traffic.
FTP - File Transfer Protocol: Our FTP server is only available to registered dealers but it allows us to have a centralised repository of all software and technical bulletins.
Kernel - The kernel relates in "device terms" as the core of the operating system of the device. The kernel manages data from the hardware and devices to the various applications and services.
App - This is the application or program that provides the user interface, interprets input from the user and performs actions based on that input or from other sources eg. Network or Servers
Codec - A codec is an agreed communications protocol between devices, it determines how much bandwidth or compression the voice packets will be using. Common codecs are G.711 / G.729 / G.723 and are widely used by VoIP devices.
Default Gateway - This is used in IPV4 networking when any IP device that needs to communicate to a device OUTSIDE of its own network; will require a device to get to other IP networks. This is most commonly your router or internet modem that has an active internet connection. IP devices can often have more than one gateway or static route but only ever ONE default gateway. The Default Gateway is your devices' first stop to get outside of its own network.
Router - A router is an IP device that moves packets from one network to another or many. A router works on many different layers in data networking.
Firewall - A firewall stops external computers & devices connecting (or hacking) your devices within your network. It can also perform PORT FORWARDING and NAT to service different devices within your network such as web servers or IP Telephone systems.
NAT - Network Address Translation: The act of manipulating the internal IP address range eg. 192.168.2.101 to an external IP address eg. 22.214.171.124. The router/firewall tracks the OUTGOING request and port number and communicates to the outside device on your behalf.
Your PC is 192.168.2.103 with an outside address of 126.96.36.199
You browse to "www.nine-one-one" = http://188.8.131.52:80
The router / firewall takes your request and stores it in memory but maps the request to a random port eg. 34221
From the outside world webserver perspective it will see a request for the webpage from 184.108.40.206:34221 so when it sends the data for the webpage back to 220.127.116.11:34221 the router knows that its for your PC (192.168.2.103) and sends it back to your PC's web browser.
Ports - IP uses "ports" to provide multiple, simultaneous connections to various applications and services. Common ports are 21(FTP), 25(SMTP) and 80(HTTP). Any port below 1024 is considered "privellidged" and are reserved for specific applications and services. Any port above 1024 is free to be used by application developers. These rules have been set down by the IETF for many years and are standard across all operating systems.
TCP - Transmission Control Protocol: This is a connection oriented protocol, where each party involved in the data tranmission acknowledges they have recieved the data or will request a re-transmission of the packet. It is slower than its counterpart UDP because of the error correction and handshaking involved but it ensures that the data is delivered correctly.
UDP - User Datagram Protocol: This is a connectionless protocol, the transmitter will send out the data to anyone requesting it however there is no error correction, handshaking or retransmitting of the data. It is used mainly in streaming media or services that require fast and best-effort connectivity such as VoIP.