3.10 VoIP

Voice over IP network (VoIP) enables you to use your broadband Internet connection to make toll quality voice calls over the Internet.

There are many different call signaling protocols, methods by which VoIP devices can talk to each other. The most popular protocols are SIP, MGCP, Megaco and H.323. These protocols are not all compatible with each other (except via a soft-switch server).

The Vigor V models support the SIP protocol as this is an ideal and convenient deployment for the ITSP (Internet Telephony Service Provider) and softphone and is widely supported. SIP is an end-to-end, signaling protocol that establishes user presence and mobility in VoIP structure. Every one who wants to talk using his/her SIP Uniform Resource Identifier, “SIP Address”. The standard format of SIP URI is

sip: user:password @ host: port

Some fields may be optional in different use. In general, "host” refers to a domain. The “userinfo” includes the user field, the password field and the @ sign following them. This is very similar to a URL so some may call it “SIP URL”. SIP supports peer-to-peer direct calling and also calling via a SIP proxy server (a role similar to the gatekeeper in H.323 networks), while the MGCP protocol uses client-server architecture, the calling scenario being very similar to the current PSTN network.

After a call is setup, the voice streams transmit via RTP (Real-Time Transport Protocol). Different codecs (methods to compress and encode the voice) can be embedded into RTP packets. Vigor V models provide various codecs, including G.711 A/µ-law, G.723, G.726 and G.729 A & B. Each codec uses a different bandwidth and hence provides different levels of voice quality. The more bandwidth a codec uses the better the voice quality, however the codec used must be appropriate for your Internet bandwidth.

Usually there will be two types of calling scenario, as illustrated below:

zCalling via SIP Servers

First, the Vigor V models of yours will have to register to a SIP Registrar by sending registration messages to validate. Then, both parties’ SIP proxies will forward the sequence of messages to caller to establish the session.

If you both register to the same SIP Registrar, then it will be illustrated as below:

The major benefit of this mode is that you don’t have to memorize your friend’s IP address, which might change very frequently if it’s dynamic. Instead of that, you will

Vigor2910 Series User’s Guide

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Draytek 2910 manual VoIP, Sip userpassword @ host port, Calling via SIP Servers

2910 specifications

The DrayTek 2910 is a versatile and robust router designed primarily for small to medium-sized businesses, offering a wide array of features that cater to various networking needs. With its advanced capabilities, it delivers superior performance and flexibility for organizations that demand reliable internet connectivity.

One of the defining characteristics of the DrayTek 2910 is its dual WAN capabilities. This allows users to connect two different internet service providers, ensuring that the network remains operational even if one connection fails. The router can automatically switch between the WANs, providing seamless failover and load balancing. This feature is essential for businesses that require constant uptime and reliability.

The DrayTek 2910 is equipped with multiple Ethernet ports, enabling it to support various devices and create a robust local area network (LAN). The router includes VLAN support, which allows for the segmentation of the network into different virtual networks, enhancing security and performance by isolating sensitive data traffic.

Another notable aspect of the DrayTek 2910 is its comprehensive security features. It includes a built-in firewall, which protects the network from external threats and unauthorized access. The router supports various protocols, including VPN (Virtual Private Network), allowing secure remote access to the network. This capability is particularly beneficial for businesses with remote workers or those needing secure connections for branch offices.

DrayTek has also integrated advanced Quality of Service (QoS) features in the 2910, which prioritize bandwidth allocation to critical applications, ensuring that essential services receive the needed resources. This is crucial for maintaining the performance of VoIP (Voice over Internet Protocol) calls and video conferencing tools, which are increasingly vital in today’s business environment.

In terms of management, the DrayTek 2910 offers easy configuration through a user-friendly web interface, allowing administrators to set up and monitor the network with minimal effort. The device also supports TR-069 for remote management, enabling service providers to configure and monitor the router without requiring an on-site visit.

Overall, the DrayTek 2910 stands out for its blend of reliability, security, and performance, making it an excellent choice for businesses looking to enhance their networking capabilities while ensuring a secure and efficient operation. With its rich set of features and technologies, the DrayTek 2910 continues to be a preferred router for many organizations worldwide.