As the pace of VoIP adoption among small and medium-sized businesses continues to grow, larger corporations which have been enjoying success with deployments of cloud technologies in their marketing divisions and call centers are also looking to Voice over Internet Protocol as a way forward for enhanced service provision.
Providers and vendors have responded in kind, with offerings and promises of advanced VoIP features that are “enterprise-ready”. In this article, we’ll look at the considerations that large-scale enterprises need to be aware of to ensure that their systems and network infrastructure are ready to make the most of VoIP.
The first thing enterprise users should bear in mind is that a VoIP system must share the same network as their other workloads and applications. The speed and smoothness of data transmission across the network will have a significant impact on VoIP, which is greatly sensitive to latency, jitter, and packet loss.
So before deploying a VoIP system, it’s essential to conduct a network analysis to determine where bottlenecks occur, and to set a base level for normal network performance in the absence of VoIP. Given the maximum number of simultaneous calls expected at any given time, the presence of other network data in the pipe, and the codecs selected for the system, this analysis should reveal where issues of insufficient bandwidth may occur on local or wide area network links where VoIP traffic is due to be passing.
These observations will determine whether it’s necessary to negotiate a higher speed link with your internet service provider, and/or whether routers and hubs on the network will require upgrading. This is also the time to assess network security, and to ensure that your infrastructure is protected from malware and intrusions.
Enabling Quality of Service (QoS)
On a mission-critical platform such as enterprise telecommunication, call quality is paramount – and in a successful VoIP infrastructure, Quality of Service (QoS) must be assured. This is accomplished by giving network priority to the data that originates from and travels to your VoIP system. VoIP packets should always be given top priority so they meet minimum delay on their travels – even on low-traffic networks where congestion is less of an issue. QoS needs to be enabled and configured throughout your network infrastructure.
VoIP packets typically originate or end up on IP phones and gateways, which are usually configured to automatically tag VoIP data so that QoS mechanisms like IP precedence or DiffServ-DSCP can identify and process them properly. If this identification functionality extends to other devices on your network like routers, switches, and firewalls, it’s possible to configure Quality of Service across your entire infrastructure.
To keep costs down, companies with remote sites and branch offices usually pass voice traffic over their leased lines or Wide Area Network (WAN). As WANs are generally much slower than Local Area Networks (LANs), edge routers must be configured to give top priority to VoIP packets, in order to ensure Quality of Service.
In addition, low-bandwidth codecs like G.729 should be used together with QoS and IP Real-Time Transport Protocol (RTP) header compression, to deal with packet losses and delays, and to minimize bandwidth demands on low-speed WAN links.
Setting Up Voice VLANs
With QoS properly configured, the next step is to isolate VoIP traffic in dedicated VLANs (Virtual Local Area Networks) which are set up for voice data alone. These accommodate only traffic from your VoIP infrastructure, and ensure that your VoIP PBX, voice gateways and IP phones have more bandwidth available, and enjoy an isolated and secure environment, free from any threats faced by your main network infrastructure.
Your entire VoIP infrastructure should be in its own VLAN – regardless of the size of your network, or whether it’s wired or wireless. This VLAN hosts your main VoIP PBX, IP phones, gateways, and other devices and services usually placed in a separate voice VLAN. Wireless networks also require a dedicated VLAN for wireless VoIP clients (such as WiFi).
For large organizations having several branch offices and remote sites, continuous monitoring is required to ensure that QoS remains properly configured, enabled and active on the edge routers connecting the various strands. Quality assurance should extend beyond simply monitoring, to securing and optimizing your VoIP services.
This will help guard against degradations in voice, video, and data transfer quality as network demands fluctuate.
CX And Service Control
Proper configuration, enabling Quality of Service, and edge monitoring will enhance security and communications quality in the customer-facing environment. To fully optimize the customer experience or CX, a service control center may be established to provide visibility into customer environments throughout the enterprise. With centralized monitoring and administration, service management and troubleshooting may be implemented proactively.
General Monitoring And Troubleshooting
To uncover hidden bottlenecks, identify network problems, and ensure that QoS is properly functioning, it’s essential to monitor your LAN and WAN infrastructure, and to take periodic benchmark and performance measurements. This may be done using open-source applications, commercial monitoring suites, or software coded in-house.