Headsets Cisco Phones
A VoIP phone or IP phone uses Voice over IP Headsets Cisco Phones technologies for placing and transmitting telephone calls over an IP network, such as the Internet, instead of the traditional public switched telephone network (PSTN).
Digital IP-based telephone Headsets Cisco Phones service uses control protocols such as the Session Initiation Protocol (SIP), Skinny Client Control Protocol (SCCP) or various other proprietary protocols.
Headsets Cisco Phones VoIP phones can be simple software-based soft phones or purpose-built hardware devices that appear much like an ordinary telephone or a cordless phone. Traditional PSTN phones are used as VoIP phones with analog telephone Headsets Cisco Phones adapters (ATA).
Two combined signal-and-power wired cable interfaces are in common use to communicate between computer networks (or computers) and physically separate VoIP phones: USB and Power over Ethernet. The latter is preferred in industry such as large scale call centers or PBX replacement applications, because PoE has the following advantages over USB:
- Much greater and more flexible power allocation: PoE switches typically support 4, 8, 16, 24, 48 or more ports each, with each device drawing up to 30W. By contrast, a USB 3.0 only supports up to 4.5W devices, insufficient for cordless, conference, videoconferencing and other common-use devices.
- Much greater cord range. While DC power diminishes rapidly over long cables, and is inefficient to supply further than 3m for high-draw devices, the low power draw of modern indoor radios permits full use of cat5 Ethernet cables of up to 100m length. By contrast USB supports under 3m and with extensions and boosters perhaps 10m maximum.
- Single connector: PoE relies on the single uniform RJ-45 connector, a close relative of the proven RJ-11 connector used for analog phones. By contrast there are six USB connectors and each change to the USB standard so far has involved at least one new type of connector.
- Ethernet protocol: Scalable from its original 1 megabit to modern 100 gigabit applications, copper Ethernet has no peer for availability Headsets Cisco Phones. It makes effective use of many different cable types (especially cat3 and coaxial cable) and has robust wireless equivalents (802.11/WiFi) when power and wired security is not required.