VoIP和PSTN之间的区别

1.互联网协议语音(VoIP)：
VoIP代表Internet语音协议，也称为IP电话或Internet电话或宽带电话。简单来说，它是指Internet上的电话服务。该技术允许使用宽带Internet连接而不是常规电话线进行语音呼叫。它用于通过Internet协议(IP)网络传送高范围语音通信以及多媒体会话，这就是为什么将其称为IP语音。现在，这是在人与人之间传递声音的最有效方法之一。

在VoIP中，通过使用(互联网协议)IP以分组的形式发送语音数据，互联网被用作电话呼叫的传输介质。它将实时语音信号从源IP地址传输到目标IP地址。当前，互联网协议语音(VoIP)是早期/传统电话服务的可靠且具有成本效益的替代方案之一。

2.公用电话交换网(PSTN)：
PSTN代表公共交换电话网络，也称为传统电路交换电话网络，以前称为唯一的公共电话网络。 PSTN是指允许不同站点的人们之间进行语音通信的电信网络。 公共交换电话网使用了一种古老的技术，该技术使用铜线来传输模拟语音信号。它由本地，国家和国际运营商运营。

公共交换电话网基于电路交换概念。当在两部电话之间建立专用路径时，会在它们之间建立电路。所有座机都是公共交换电话网(PSTN)。

VoIP和PSTN之间的区别：

S.No.	VoIP	PSTN
01.	Voice over Internet Protocol uses packet switching.	Public Switched Telephone Network uses circuit switching.
02.	In VoIP, only an internet connection is required.	In PSTN, dedicated lines required from telecom company.
03.	No dedicated path required between sender and receiver.	Dedicated path required between sender and receiver.
04.	One VoIP lines require 100 kbps.	One link typically supports 64 kbps.
05.	In VoIP, it acquires and releases bandwidth as it is needed.	Bandwidth is reserved in advance it requires as each line is 64 kbps.
06.	In VoIP, Cost is not dependent on distance and time.	In PSTN, Cost is based on distance and time.
07.	Extensions is a standard feature of VoIP.	Extensions requires extra costs in PSTN.
08.	VoIP provides consistent voice quality but depends on bandwidth.	PSTN provides consistent voice quality.
09.	Call waiting, call forwarding, call transfer are standard features of VoIP.	Call waiting, call forwarding, call transfer are usually standard features in PSTN but sometimes it costs extra for this.
10.	Scalability and upgrades requires improved internet bandwidth.	Scalability and upgrades requires substantial hardware additions.