Hosted Voice. Best Practice Recommendations for VoIP Deployments

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1 Hosted Voice Best Practice Recommendations for VoIP Deployments

2 Thank you for choosing EarthLink! EarthLinks best in class Hosted Voice phone service allows you to deploy phones anywhere with a Broadband connection. This flexibility allows you to take your EarthLink service home or when you travel. The quality of a Voice over IP (VoIP) call is heavily dependent on the environment that call is running in. From the device placing the call, to the network characteristics and firewall/router configuration a successful VoIP deployment requires careful consideration of the end to end experience. This document is intended to share the best practices in configuring and selecting the best environment for VoIP calling over unmanaged networks using EarthLink Hosted Voice. Although unique deployment steps may vary from one network to another, most issues encountered during VoIP installations can be addressed by following a few important steps. This guide will show you some basic network configurations and provide best practice recommendations for a successful implementation. Network Topology Every network layout is unique with unique design considerations however most networks fall into one of the following categories: Install Phone Using Your Modem Your broadband modem will connect to your Service Provider A cable will connect from your modem/router to your IP phones LAN port A cable will connect your computer to the IP phone on the PC port Broadband Modem/Router Install Phone Using Your Router or WiFi Access Point Your modem will connect to your Service Provider A cable will connect the modem to your router A cable will connect your router to the IP phones LAN port A cable will connect your computer to the IP phone on the PC port Modem Customer Router Install Phone Using a Firewall Your modem will connect to your Service Provider A cable will connect the modem to your firewall A cable will connect your firewall to the IP phones LAN port A cable will connect your computer to the IP phone on the PC port

3 Recommended Configurations Configuration changes may be needed on one or more devices on your network depending on the network layout. Installation Using Your Modem Connecting your phone directly to the modem/router provided by your Service Provider (ISP) usually requires the least configuration changes. Disable SIP Aware features on the modem Different vendors refer to SIP aware functionality by different names but it is often referred to as SIP Application Layer Gateway (ALG), Stateful Packet Inspection (SPI) or SIP NAT. These settings are commonly found in the firewall, security, advanced or WAN configuration page, but may also be elsewhere on the settings. Disable firewall features on your modem Installation Using Your Router or WiFi Access Point The need for an additional router or WiFi Access Point may prevent you from plugging the phone directly to your modem. Set your modem to Bridge Mode This allows your internet connection be handled by your router; in essence you are building a bridge so that traffic travels through your modem directly to your router. Disable SIP Aware features on your router Disable firewall features on your router Installation Using a Firewall Firewalls are advanced applications meant to protect your network by inspecting all data and allowing valid traffic while rejecting anything unauthorized. While some firewalls are software within your router, others can be an external device on your network. When using a firewall, rules need to be configured to ensure the EarthLink voice and phone provisioning traffic is allowed access. Set your modem to Bridge Mode This allows your internet connection be handled by your router; in essence you are building a bridge so that traffic travels through your modem directly to your firewall. Disable SIP Aware features on your firewall Add IP addresses required for EarthLink voice services to the allowed/whitelist on the firewall Due to the variety of Service Providers and network hardware manufactures it is not possible to detail the exact steps needed to make the required network changes. For assistance in completing the configuration changes please contact your ISP or hardware manufacture.

4 Implementation Best Practices Network Design Recommendations Double-NAT Whenever possible the IP phone should connect directly to the modem/router provided by your internet service provider. Many larger networks require the addition of routers, switches, firewalls. When there is more than one router between the phone and the internet, it will create a double NAT topology causing phones to not register, receive one-way audio or no audio at all. Double-NATing is known to cause many problems for VoIP phones and is not a supported topology. If utilizing a router, the modem should be in bridged mode. Below are some examples of common topologies where double NAT exists: Double NAT Double NAT Modem with NAT Wireless Router Modem with NAT Firewall EarthLink recommends only one device performing NAT between the phone and the internet. VLANs Virtual Local Area Networks (VLANs) allow you to segment the IP phones on your network onto separate virtual networks. VLANs allow you to create separate rules and configurations that only apply to the IP phones and are highly recommended. The s utilize the industry standard Layer Link Discovery Protocol (LLDP) to identify themselves as IP phones. When used in combination with a LLDP-Supported switch, VLANS allow for easy implementation of Hosted Voice. EarthLink recommends utilizing a LLDP capable switch and segmenting phones onto a separate VLAN. DHCP Using the Dynamic Host Configuration Protocol (DHCP), when EarthLink Hosted Voice phones boot they need to acquire their configurations. Initial configurations are retrieved via TFTP from To assist in easy installation, the phones can acquire boot server information from the network Dynamic Host Configuration Protocol (DHCP) server. EarthLink recommends that your DHCP server is configured with DHCP Option 66 to

5 Firewall and Security Recommendations Firewalls are intended to protect your network from unauthorized traffic and to ensure the security of your data. Generally speaking, you do not want voice traffic passing through your firewall but if needed, the following should be implemented: Disable any SIP (Session Initiation Protocol) aware functionality SIP ALG (Application Layer Gateway), SIP NAT, SPI(Stateful Packet Inspection), SIP Fixup There should be no manipulation or translation of the SIP Messaging Configure rules to allow traffic to the EarthLink Voice Network See the table below for a list of IPs the phones need to receive and send traffic IP Address Protocol Port UDP/TCP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP SIP/RTP All UDP TFTP 69 UDP HTTP 80 TCP HTTPS 443 TCP HTTP 80 TCP HTTPS 443 TCP HTTP 80 TCP HTTPS 443 TCP

6 Quality of Service (QoS) Recommendations When making a Voice over IP (VoIP) call, the sound of your voice is converted to digital information and broken into thousands of pieces known as packets. These packets travel through the to the EarthLink voice network. Latency (the time it takes a voice packet to reach its destination), jitter (variation of latency within the network) and packet loss (dropped/disgarded packets) are the most common issues to impact voice quality. Network congestion can delay or drop packets and even a few dropped packets on a voice data stream can introduce echo, breaks in voice conversation or dropped calls. While it is not possible to guarantee reliable delivery of packets that are sent over the public internet, ensuring the voice traffic has the highest priority and sufficient bandwidth within your office network will provide the highest possible quality voice communications. DSCP Tagging To ensure the best possible voice quality, EarthLink will mark all VoIP traffic so it can be prioritized on your network. EarthLink s Hosted Voice phones are configured to use DSCP (Differentiated Services Code Point) 46 for all VoIP traffic. Bandwidth Like browsing the internet or streaming music, each phone call you make is utilizing your internet bandwidth. It is important that there is sufficient bandwidth to ensure high quality calls. Each phone call utilizes approximately 100 kbps of bandwidth including calls between two phones at the same site. EarthLink recommends for the customer s equipment to match and prioritize all traffic marked with DSCP 46. When spikes in network traffic occur, the router/modem should throttle the traffic to allow sufficient bandwidth for the voice. Note that while using non-earthlink provided internet/network access, EarthLink cannot guarantee call quality and QoS outside of EarthLink s own network infrastructure. IMPORTANT: The FCC requires that providers of IP-based phones services remind you of important 911 Service information. EarthLink requires an updated and accurate service address to insure that emergency 911 services can be dispatched to your actual location. If you move your equipment location, contact EarthLink Customer Care at in advance to provide your new address. 911 callers need to know the address and telephone number of their location when contacting emergency services. If your electricity or internet services are down due to an outage or other technical issue, 911 emergency services may not function. Contact us at EL-CARE-1 customercare@earthlinkbusiness.com 2016 EarthLink. Trademarks are property of their respective owners. All rights reserved. MKTPRINT-258