An IP telephone system uses packet-switched Voice over IP (VoIP) or Internet telephony, to transmit telephone calls over the Internet, as opposed to the circuit-switched telephony used by the traditional Public Switched Telephone Network (PSTN). IP telephone systems typically comprise of a VoIP private branch exchange (an IP PBX) and desktop VoIP phones (IP Phones) that connect to a service provider, via a Local Area Network (LAN)
An IP based voice and camera communications system for use within a building or collection of buildings that can provide access control and live monitoring. Can be integrated with an existing Access Control, CCTV or Security System. Remote access can also be available through your smart phone.
Internet Management refers specifically to an administrator's insight into and control over what users do online while they are using the private, guest or company networks. Security separation and controls are put into place to limit specific uses.
A walkie-talkie is a two-way radio: you can both talk and listen (send and receive). The main drawback is that the same frequency channel is used for both things, so only one person can talk at a time.
Pros : Walkie-talkies are robust, easy-to-use, and simple, so they're brilliant for use outdoors and great for children (or for children who need to stay in touch with parents, for example, on vacation). They're particularly handy in places where cellphone network coverage is poor or unavailable (in disasters or emergencies, for example). They're very handy in situations where lots of people need to listen and only one needs to talk at once (for example, if you're giving instructions to workers on a camp site). They work over a decent range (typically 5–10 square km); and have long battery life (20 hours typical).
Cons : Most inexpensive walkie-talkies are analog units, so they're subject to interference and relatively easy to eavesdrop (more expensive digital units get around interference, but generally only military walkie-talkies use encryption to overcome eavesdropping). Walkie-talkies are not designed for communication over longer ranges (for which you'll need something like CB radio or a cellphone).