Voice over Internet Protocol
What does a codec do?
A codec is a device or computer program which encodes or decodes a digital data stream or signal or compresses and decompresses medial files.
16. How can you group IP phone?
A voice VLAN is used to group together IP Phones.
All VoIP calls are dependent on what two qualities of the IP network?
All VoIP calls are dependent on the quality and reliability of the IP network they utilize. For VoIP calls that need to traverse the Internet, the quality of the call is also dependent on the quality and reliability of the Internet connection in use. Also, if the IP network components lose power, VoIP services will not work until power is restored.
15. Define DSCP and what it uses in the header.
Differentiated Services Code Point (DSCP) is a means of classifying and managing network traffic and of providing quality of service (QoS) in modern layer 3 IP networks. It uses the 6-bit differentiated Service (DS) field in the IP header for the purpose of packet classification.
12. Define QoS. What factors does QoS use to prioritize traffic?
From the perspective of an IP network, the term Quality of Service (QoS) refers to the ability to give priority to certain types of network traffic based on the application, user, or service that generated the traffic. packet delay, packet loss, and packet jitter.
10. PSTN is analog phone whereas VoIP is __________ phone.
IP phone
17. What is the difference between VoSIP and SVoIP?
In a SVoIP implementation, the VoIP components are connected to an unsecure network. This makes the IP phone responsible for encrypting the voice traffic before the voice traffic is sent on to the IP network. VoSIP is another VoIP implementation used to transmit secure voice communications. In a VoSIP implementation, the VoIP components are connected to a secure IP network. This means the IP network itself is authorized to store and transmit classified information.
13. What does the router do for a packet?
In order for devices in different subnets to communicate with each other, a network router is required to forward the packets from one subnet to another.
14. What is the network switch used for?
Network switches provide the physical connectivity for any device to access an IP network. Network switches also provide traffic forwarding for any device that is connected to it.
What is the difference between proprietary and non-proprietary?
Non-proprietary means a protocol can be used by anyone or any organization free of charge. A non-proprietary protocol is usually developed by a standards organization as a way to facilitate interoperability between manufacturers of VoIP components. Proprietary means a protocol is owned by a particular entity, usually a private company such as Cisco or Avaya.
Which of the named VOIP protocols are proprietary? Which are non-proprietary?
Proprietary- Skinny Client Control Protocol (SCCP or Skinny) Non-Proprietary- H.323, Session Initiation Protocol (SIP), Real-Time Transport Protocol (RTP)
11. QoS is implemented on which layer 3 network device?
Routers
In what scenario, would you utilize a voice gateway?
Voice Gateways provide connectivity between VoIP components and PSTN components. Without a Voice Gateway, a VoIP user could not call a PSTN user and vice versa.
_____ is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks.
Voice over Internet Protocol (VoIP)
Describe the 5 major VoIP components.
• Endpoint Devices In an IP network, endpoint devices are IP Phones, soft phone applications, computers, printers, and even smart speakers count. If the human interfaces with the device directly and uses it, it's an "endpoint device". • Call Processing Server: Call processing servers are commonly called Call Managers. The Call Processing Server stores end device IDs, directory numbers, configuration settings, and establishes calls. It is a program installed on a computer • Voice Gateways: Voice Gateways provide connectivity between VoIP components and PSTN components. Without a Voice Gateway, a VoIP user could not call a PSTN user and vice versa. • VoIP Protocols: A protocol is a standard procedure or set of rules that defines how communications devices should communicate with each other and transmit data. VoIP protocols specifically define how IP Phones, Call Managers, and Voice Gateways should communicate with each other. • IP Network: The IP Network provides the infrastructure, or backbone, necessary for a VoIP implementation. IP Phones, Call Managers, and Voice Gateways do not have direct physical connections to each other. Therefore, for these devices to communicate with each other, they must physically connect to the IP Network. The IP Network is then responsible for transmitting VoIP traffic from one VoIP component to another.
