Network requirements for voice support with Talk

<body>
<p id="docs-hc-snippet" style="display: none;">Zendesk uses the internet for making and receiving phone calls. As a result, a fast and reliable internet connection is important. For example, a wired network with Wi-Fi turned off gives better results. Regardless of your network configuration, you may have to make adjustments to it for the network to work properly for voice support.</p>
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<p id="docs-ai-summary-toggle">Summary: <span id="up-triangle">◀</span><span id="down-triangle">▼</span></p>
<p id="docs-ai-summary-content">Ensure a fast, wired internet connection and wired headsets for voice support to reduce latency, jitter, and packet loss. Allow required IPs, ports, and URLs for media and signaling traffic, and configure split tunnels for VPNs or proxies. Use DSCP tags to prioritize voice packets, especially in Windows environments. Troubleshoot by disabling blocking software and running diagnostics to maintain call quality and access all voice features.</p>
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<div class="body">

<p class="p">Zendesk uses the internet for making and receiving phone calls. As a result, a fast and reliable
internet connection is important. For example, a wired network with Wi-Fi turned off
gives better results. Regardless of your network configuration, you may have to make
adjustments to it for the network to work properly for voice support. </p>
<p class="p">Use the information in this article to help minimize network problems. If you can't make
these changes yourself, contact your IT department for assistance. </p>
<p class="p">Topics covered in this article:</p>
<div class="p">
<ul class="ul" id="talk_network_requirements__ul_tkf_rj2_sxb">
<li class="li"><a class="xref" href="#topic_tpl_j35_g1c">How a network's configuration can affect voice support</a></li>
<li class="li"><a class="xref" href="#topic_vy5_sj2_sxb">Preparing your network for voice support</a></li>
<li class="li"><a class="xref" href="#topic_wcp_yxz_c1c">Using voice with a proxy, MPLS, or VPN</a></li>
<li class="li"><a class="xref" href="#topic_rjq_rzz_c1c">Using Differentiated Services Code Point (DSCP)</a></li>
<li class="li"><a class="xref" href="#topic_ptb_5j2_sxb">Troubleshooting</a></li>
</ul>
</div>
<div class="p">Related article: <ul class="ul" id="talk_network_requirements__ul_nfr_bn5_bfc">
<li class="li"><a class="xref" href="https://support.zendesk.com/hc/en-us/articles/4408827987482" target="_blank">Preparing to offer voice support</a></li>
</ul>
</div>
</div>
<div aria-labelledby="ariaid-title2" class="topic nested1" id="topic_tpl_j35_g1c">
<h2 class="title topictitle2" id="ariaid-title2">How a network's configuration can affect voice support</h2>
<div class="body">
<p class="p">A network's configuration can have a significant impact on the following:</p>
<ul class="ul" id="topic_tpl_j35_g1c__ul_hkk_pj2_sxb">
<li class="li">
<strong class="ph b">Latency</strong>: The time it takes data packets to arrive at the destination.
High latency means there are significant delays in transmitting the data over
the network, which result in interruptions such as voice delivery delays that
can cause overlaps in conversation. Lower latency creates a smoother call
experience.</li>
<li class="li">
<strong class="ph b">Jitter</strong>: The change in latency over time. Jitter sounds similar to
interference or as though someone is having problems with their microphone
connection. It can also lead to one side of the conversation not being heard
clearly.</li>
<li class="li">
<strong class="ph b">Packet loss</strong>: When voice signals are digitized and transmitted, they are
divided into data packets. If some of the packets fail to reach their
destination, the result is missing pieces of the audio signal causing audible
voice distortion to the call.</li>
</ul>
<p class="p">To minimize network issues, ensure everything is wired. Use wired 3.5mm jack headsets
for agents and a wired internet connection instead of a Wi-Fi one.</p>
<p class="p">Some applications use a lot of bandwidth, especially streaming apps. Zendesk requires
500kbps per agent providing voice support. If you have 50 agents, for example, they
would each need a dedicated 500kbps, meaning a minimum 25mbps line. </p>
<p class="p">A best practice when troubleshooting network issues is to first close all
network-intensive applications such as Netflix, Spotify, and YouTube.</p>
</div>
</div>
<div aria-labelledby="ariaid-title3" class="topic nested1" id="topic_vy5_sj2_sxb">
<h2 class="title topictitle2" id="ariaid-title3">Preparing your network for voice support</h2>
<div class="body">
<div class="p">Zendesk uses Twilio as its network provider. If you're applying traffic filtering,
you must allow network access to the list of IP addresses, ports, domains, and URLs
listed in this section.<div class="note note">
<span class="notetitle">Note:</span> Zendesk is hosted by Amazon Web Services (AWS). Ensure
you permit all of the AWS IP ranges that are specified in <a class="xref" href="https://support.zendesk.com/hc/en-us/articles/4408842860186" target="_blank">Configuring your firewall for use with
Zendesk</a>.<p class="p">This section covers the following topics:</p>
<div class="p">
<ul class="ul" id="topic_vy5_sj2_sxb__ul_q5p_x5g_d1c">
<li class="li"><a class="xref" href="#topic_vy5_sj2_sxb__section_hq4_5gz_c1c">Required IP addresses, ports, and domains for voice</a></li>
<li class="li"><a class="xref" href="#topic_vy5_sj2_sxb__section_ybd_t4z_c1c">Required URLs for voice</a></li>
<li class="li"><a class="xref" href="#topic_vy5_sj2_sxb__section_m5q_45z_c1c">Recommendations and incompatibilities</a></li>
</ul>
</div>
</div>
</div>
<div class="section" id="topic_vy5_sj2_sxb__section_hq4_5gz_c1c">
<h3 class="title sectiontitle">Required IP addresses, ports, and domains for voice</h3>
<p class="p">There are three types of traffic that need to make outbound connections, and in
response, allow return traffic:</p>
<div class="p">
<ul class="ul" id="topic_vy5_sj2_sxb__ul_syg_dhz_c1c">
<li class="li">Media traffic — a Secure Real-time Transport Protocol (SRTP) connection
used to send and receive primary call audio.</li>
<li class="li">Signaling traffic — an encrypted Transport Layer Security (TLS)
connection used for sending and receiving control information to set up and manage
calls.</li>
<li class="li">Fallback traffic — a Network Traversal Service (STUN/TURN) connection
used as a mandatory safety net to maintain audio streaming if direct media paths are blocked.</li>
</ul>
</div>
<div class="p">
<div class="note note">
<span class="notetitle">Note:</span> Ensure that any changes you make to your configuration are applied across
all network appliances. This includes firewalls, routers, switches,
load-balancers, and any other hardware or software (including software-based
blocking systems) that could block or interfere with network traffic. </div>
</div>
<div class="p">
<div class="tablenoborder">
<table border="1" cellpadding="4" cellspacing="0" class="table" frame="border" id="topic_vy5_sj2_sxb__table_zqz_jsp_g1c" rules="all" summary="">
<colgroup>
<col style="width:40.15267175572519%">
<col style="width:22.442748091603054%">
<col style="width:22.137404580152673%">
<col style="width:15.267175572519085%">
</colgroup>
<tbody class="tbody">
<tr class="row">
<td class="entry cellrowborder" colspan="4" style="text-align:left;vertical-align:top;"><strong class="ph b">Media connections</strong></td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Secure media (ICE/STUN/SRTP) edge
locations</strong></td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Destination IP ranges</strong></td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Destination port ranges</strong></td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Protocol</strong></td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Sydney (au1)<p class="p">São Paulo (br1)</p>
<p class="p">Dublin
(ie1)</p>
<p class="p">Frankfurt (de1)</p>
<p class="p">Tokyo
(jp1)</p>
<p class="p">Singapore (sg1)</p>
<p class="p">Ashburn
(us1)</p>
<p class="p">Umatilla (us2)</p>
<p class="p">Roaming
(gll)</p>
</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">168.86.128.0/18</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">10,000 - 60,000</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">UDP</td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="note note">
<span class="notetitle">Note:</span> You cannot specify IP ranges for signaling connections. Instead, you must
activate communication to the domains listed in the following Signaling
connections table. If your internal network environment requires that you add
each connecting IP to an allow list, we suggest hosting a server outside your
network (such as a network DMZ) to proxy requests from Twilio into the internal
network.
</div>
<div class="p">
<div class="tablenoborder">
<table border="1" cellpadding="4" cellspacing="0" class="table" frame="border" id="topic_vy5_sj2_sxb__table_lny_ltp_g1c" rules="all" summary="">
<colgroup>
<col style="width:39.2688679245283%">
<col style="width:33.37264150943396%">
<col style="width:15.566037735849056%">
<col style="width:11.792452830188678%">
</colgroup>
<tbody class="tbody">
<tr class="row">
<td class="entry cellrowborder" colspan="4" style="text-align:left;vertical-align:top;"><strong class="ph b">Signaling
connections</strong></td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Description</strong></td>
<td class="entry cellrowborder" style="vertical-align:top;"><strong class="ph b">Destination</strong></td>
<td class="entry cellrowborder" style="vertical-align:top;"><strong class="ph b">Destination port</strong></td>
<td class="entry cellrowborder" style="vertical-align:top;"><strong class="ph b">Protocol</strong></td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Secure TLS connection to Twilio signaling gateway</td>
<td class="entry cellrowborder" style="vertical-align:top;">
<ul class="ul">
<li class="li">chunderw-gll.twilio.com</li>
<li class="li">chunderw-vpc-gll.twilio.com</li>
<li class="li">voice-js.roaming.twilio.com</li>
</ul>
</td>
<td class="entry cellrowborder" style="vertical-align:top;">443</td>
<td class="entry cellrowborder" style="vertical-align:top;">TCP</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Secure TLS connection to Twilio regional signaling
gateways</td>
<td class="entry cellrowborder" style="vertical-align:top;">
<ul class="ul">
<li class="li">chunderw-vpc-gll-au1.twilio.com</li>
<li class="li">chunderw-vpc-gll-br1.twilio.com</li>
<li class="li">chunderw-vpc-gll-de1.twilio.com</li>
<li class="li">chunderw-vpc-gll-ie1.twilio.com</li>
<li class="li">chunderw-vpc-gll-jp1.twilio.com</li>
<li class="li">chunderw-vpc-gll-sg1.twilio.com</li>
<li class="li">chunderw-vpc-gll-us1.twilio.com</li>
<li class="li">chunderw-vpc-gll-us2.twilio.com</li>
<li class="li">voice-js.ashburn.twilio.com</li>
<li class="li">voice-js.sydney.twilio.com</li>
<li class="li">voice-js.dublin.twilio.com</li>
<li class="li">voice-js.sao-paulo.twilio.com</li>
<li class="li">voice-js.frankfurt.twilio.com</li>
<li class="li">voice-js.tokyo.twilio.com</li>
<li class="li">voice-js.singapore.twilio.com</li>
<li class="li">voice-js.umatilla.twilio.com</li>
<li class="li">voice-js.roaming.twilio.com</li>
</ul>
</td>
<td class="entry cellrowborder" style="vertical-align:top;">443</td>
<td class="entry cellrowborder" style="vertical-align:top;">TCP</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Secure TLS insights logging gateway</td>
<td class="entry cellrowborder" style="vertical-align:top;">
<ul class="ul" id="topic_vy5_sj2_sxb__ul_sq1_ztp_g1c">
<li class="li">eventgw.twilio.com</li>
</ul>
</td>
<td class="entry cellrowborder" style="vertical-align:top;">443</td>
<td class="entry cellrowborder" style="vertical-align:top;">TCP</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">-</td>
<td class="entry cellrowborder" style="vertical-align:top;">
<ul class="ul" id="topic_vy5_sj2_sxb__ul_fyh_ytp_g1c">
<li class="li">sdk.twilio.com</li>
</ul>
</td>
<td class="entry cellrowborder" style="vertical-align:top;">443</td>
<td class="entry cellrowborder" style="vertical-align:top;">TCP</td>
</tr>
</tbody>
</table>
</div>
</div>
<p class="p">WebRTC relies on a Network Traversal Service (STUN/TURN) as a mandatory fallback layer.
While calls normally connect directly to the primary Voice Media Servers
(<code class="ph codeph">168.86.128.0/18</code>), strict firewalls or NAT configurations can block
this direct path, causing dropped calls or one-way audio unless fallback servers are allowed.</p>
<div class="note important">
<span class="importanttitle">Important:</span> The Twilio Diagnostics test explicitly checks these fallback servers.
If this diagnostic test fails but live calls pass, your network lacks this critical safety
net, putting agents at risk of sudden call disruptions if primary routing conditions degrade.</div>
<p class="p">Allow the following regional STUN/TURN IP allocations and ports alongside your primary
media requirements:</p>
<div class="p">
<div class="tablenoborder">
<table border="1" cellpadding="4" cellspacing="0" class="table" frame="border" id="topic_vy5_sj2_sxb__table_global_stun_turn_fallback" rules="all" summary="">
<colgroup>
<col style="width:22.22222222222222%">
<col style="width:33.33333333333333%">
<col style="width:44.44444444444444%">
</colgroup>
<tbody class="tbody">
<tr class="row">
<td class="entry cellrowborder" colspan="3" style="text-align:left;vertical-align:top;"><strong class="ph b">STUN/TURN Fallback infrastructure</strong></td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Edge location</strong></td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Destination CIDR blocks</strong></td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;"><strong class="ph b">Port and protocol requirements</strong></td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Sydney (au1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">3.25.42.128/25</li>
<li class="li">13.210.2.128/27</li>
<li class="li">54.252.254.64/26</li>
</ul>
</td>
<td class="entry cellrowborder" rowspan="9" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">
<strong class="ph b">3478</strong> (UDP, TCP) — Standard STUN/TURN port</li>
<li class="li">
<strong class="ph b">443</strong> (TCP) — TURN over TLS fallback port</li>
<li class="li">
<strong class="ph b">5349</strong> (TCP) — TURN over TLS secure port</li>
<li class="li">
<strong class="ph b">10,000 - 60,000</strong> (UDP) — Dynamic peer relay
ports</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">São Paulo (br1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">18.230.125.0/25</li>
<li class="li">18.231.105.32/27</li>
<li class="li">177.71.206.192/26</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Frankfurt (de1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">18.156.18.128/25</li>
<li class="li">18.195.48.224/27</li>
<li class="li">52.59.186.0/27</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Mumbai (in1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">3.7.35.128/25</li>
<li class="li">52.66.193.96/27</li>
<li class="li">52.66.194.0/26</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Dublin (ie1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">3.249.63.128/25</li>
<li class="li">54.171.127.192/26</li>
<li class="li">52.215.127.0/24</li>
<li class="li">52.215.253.0/26</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Tokyo (jp1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">13.115.244.0/27</li>
<li class="li">18.180.220.128/25</li>
<li class="li">54.65.63.192/26</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Singapore (sg1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">13.229.255.0/27</li>
<li class="li">18.141.157.128/25</li>
<li class="li">54.169.127.128/26</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Ashburn (us1)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">3.235.111.128/25</li>
<li class="li">34.203.250.0/23</li>
<li class="li">34.203.254.0/24</li>
<li class="li">54.172.60.0/23</li>
</ul>
</td>
</tr>
<tr class="row">
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">Umatilla (us2)</td>
<td class="entry cellrowborder" style="text-align:left;vertical-align:top;">
<ul class="ul">
<li class="li">34.216.110.128/27</li>
<li class="li">44.234.69.0/25</li>
<li class="li">54.244.51.0/24</li>
</ul>
</td>
</tr>
</tbody>
</table>
</div>
</div>
</div>
<div class="section" id="topic_vy5_sj2_sxb__section_ybd_t4z_c1c">
<h3 class="title sectiontitle">Required URLs for voice</h3>
<p class="p">For some
features to work, you must be able to connect to URLs such as
<strong class="ph b">pubsub-shardC-P-N.zendesk.com</strong>. This is because voice connections are
not made via the same URL as the connection requests to the rest of Zendesk (for
example, mydomain.zendesk.com). Instead, voice connections use the following
format: <strong class="ph b">pubsub-shardC-P-N.zendesk.com</strong>. Example:
https://pubsub-shard2-17-1.zendesk.com.</p>
<ul class="ul" id="topic_vy5_sj2_sxb__ul_l1q_fsz_c1c">
<li class="li">C is the cluster of the account (a value between 1 and 3)</li>
<li class="li">P is <a class="xref" href="https://support.zendesk.com/hc/en-us/articles/4408829092506" target="_blank">the pod</a> of the account</li>
<li class="li">N is a random number from 1 to 4</li>
</ul>
You can check the URL that your account uses by checking the connection request
in Google Chrome.<p class="p"><strong class="ph b">To identify your pubsub-shardC-P-N.zendesk.com
connections</strong></p>
<ol class="ol" id="topic_vy5_sj2_sxb__ol_m1q_fsz_c1c">
<li class="li">Open Chrome and click the <strong class="ph b">Options</strong> (<img class="image" height="14" id="topic_vy5_sj2_sxb__image_n1q_fsz_c1c" src="https://zen-marketing-documentation.s3.amazonaws.com/docs/en/macros_edit_menu_icon_vertical.png" width="5">) menu.</li>
<li class="li">Click <strong class="ph b">More tools</strong> &gt; <strong class="ph b">Developer tools</strong>.</li>
<li class="li">Go go the <strong class="ph b">Network</strong> tab (if it's hidden, click <strong class="ph b">&gt;&gt;</strong>).</li>
<li class="li">In the <strong class="ph b">Filter</strong> field, enter <strong class="ph b">pubsub</strong>.</li>
<li class="li">Refresh your browser page.</li>
<li class="li">Click one of the displayed entries, then check the <strong class="ph b">Headers</strong> tab.</li>
</ol>
After you've identified the cluster and pod number for the
pubsub-shardC-P-N.zendesk.com connections of your account, replace the C and P with
the cluster and pod number that you identified for the following URLs. You must
allow these URLs (or domains) access to your VPN, firewall, and any antivirus
software that you're using.<ul class="ul" id="topic_vy5_sj2_sxb__ul_o1q_fsz_c1c">
<li class="li">https://pubsub-shard<strong class="ph b">C</strong>-<strong class="ph b">P</strong>-1.zendesk.com</li>
<li class="li">https://pubsub-shard<strong class="ph b">C</strong>-<strong class="ph b">P</strong>-2.zendesk.com</li>
<li class="li">https://pubsub-shard<strong class="ph b">C</strong>-<strong class="ph b">P</strong>-3.zendesk.com</li>
<li class="li">https://pubsub-shard<strong class="ph b">C</strong>-<strong class="ph b">P</strong>-4.zendesk.com</li>
</ul>
</div>
<div class="section" id="topic_vy5_sj2_sxb__section_m5q_45z_c1c">
<h3 class="title sectiontitle">Recommendations and incompatibilities</h3>
<div class="p">
<ul class="ul" id="topic_vy5_sj2_sxb__ul_uzn_s5z_c1c">
<li class="li">Ensure both the Zendesk and Twilio IP addresses and domains are excluded
from Stateful Packet Inspection (SPI), or you may experience high User
Datagram Protocol (UDP) or TCP connection times.</li>
<li class="li">Twilio’s Network Traversal Service (STUN/TURN) is IPv4-only. If agents
are on IPv6 addresses, ensure IPv4 reachability by asking your provider
for IPv4 addresses.</li>
<li class="li">If your router includes the SIP Application Level Gateway (ALG) function
or SPI, deactivate both of these functions on the networks that are
using for voice.</li>
<li class="li">Do not plug in hardware that is not meant to be plugged into a smart
switch. We are aware that if a switch or other network hardware is
plugged into an incorrectly configured Cisco Smart Switch, it could
override the allowed domains and IP addresses. Therefore check with your
network team that the smart switch is configured to reflect the settings
mentioned in this article.</li>
<li class="li">The Zendesk voice channel is not compatible with virtual desktop
environments (VDIs) such as Microsoft Azure Virtual Desktop (formerly
Windows Virtual Desktop) and Citrix Virtual Apps and Desktops.</li>
<li class="li">Do not block Pendo and Segment traffic because Zendesk’s customer
analytics and in-product guidance integration relies on those services.
Blocking <code class="ph codeph">app.pendo.io</code>, <code class="ph codeph">cdn.pendo.io</code>,
and <code class="ph codeph">cdn.segment.com</code> prevents Pendo-backed guidance or
analytics from loading but it isn't required for Talk voice
connectivity. If you cannot allow these domains, contact <a class="xref" href="https://support.zendesk.com/hc/en-us/articles/4408843597850" target="_blank">Zendesk Customer Support</a> to
opt out of Pendo-backed guidance or analytics.</li>
</ul>
</div>
</div>
</div>
<div aria-labelledby="ariaid-title4" class="topic nested2" id="topic_wcp_yxz_c1c">
<h3 class="title topictitle3" id="ariaid-title4">Using voice with a proxy, MPLS, or VPN</h3>
<div class="body">
<p class="p">When you need to use a proxy, MPLS, or VPN, it's essential you configure a split
tunnel. Implementing a split tunnel is necessary for directing outgoing traffic
to Zendesk, Twilio, and your Zendesk subdomain locally. This means excluding
Zendesk and Twilio traffic from the proxy, MPLS, or VPN, allowing it to go
directly to the internet at the agent's physical location.</p>
<p class="p">The requirement for this configuration is due to the presence of Global
Low-Latency (GLL), a background service which is responsible for determining the
most efficient network path for handling calls. When proxy, MPLS, or VPN
configurations are in use, the actual locations of your agents may not be
accurately represented. Consequently, this could result in suboptimal call
routing, potential latency-related issues, and other concerns impacting call
quality.</p>
<p class="p">In scenarios where using a proxy, MPLS, or VPN is unavoidable, it's crucial to
exclude traffic intended for Zendesk and Twilio domains, including your FQDN
subdomain.zendesk.com, and the specified IP addresses outlined in the
accompanying documentation. This exclusion is critical to ensure the proper
functionality within these network configurations.</p>
</div>
</div>
<div aria-labelledby="ariaid-title5" class="topic nested2" id="topic_rjq_rzz_c1c">
<h3 class="title topictitle3" id="ariaid-title5">Using Differentiated Services Code Point (DSCP)</h3>
<div class="body">
<p class="p">Differentiated Services Code Point (DSCP) tags in packets are useful for
informing network appliances on prioritizing traffic. By default, calls have a
DSCP tag of 46. If congestion is an issue on your network, consider implementing
DSCP. The Twilio Client 1.3 and later enables DSCP by default in compatible
browsers such as Google Chrome.</p>
<p class="p">Compatible browsers tag WebRTC media packets, which permits differentiated
handling on a LAN, so real-time media can be prioritized above other network
traffic. The Differentiated Services (DS) field is located in the IPv4 header
TOS octet or the IPv6 Traffic Class octet. A DS-compliant network node (for
example, a router) includes a classifier that selects packets based on the value
of the DS field, buffer management, and packet scheduling mechanisms that are
capable of delivering the specific packet forwarding treatment indicated by the
DS field value.</p>
<p class="p">With the Twilio Client 1.3, sent RTP packets will have a DiffServ codepoint on
their local <a class="xref" href="https://www.wireshark.org/" target="_blank">Wireshark</a> packet captures. When you allow DSCP, the
WebRTC engine marks the RTP packets with EF (expedited forwarding) and the
values related to this type of forwarding:</p>
<ul class="ul" id="topic_rjq_rzz_c1c__ul_oyh_g11_d1c">
<li class="li">binary: 101 110</li>
<li class="li">hex: 0x2e</li>
<li class="li">decimal: 46</li>
</ul>
<p class="p">You must use a browser that supports WebRTC (such as Chrome or Firefox). If you
implement DSCP (recommended), use Chrome (the latest, non-beta version), as this
is the only browser that supports it.</p>
<p class="p"><strong class="ph b">To check if you're on the latest version of Chrome</strong></p>
<div class="p">
<ol class="ol" id="topic_rjq_rzz_c1c__ol_ukc_cv2_d1c">
<li class="li">In Chrome, navigate to chrome://help/ in your address bar. </li>
<li class="li">Click <strong class="ph b">Relaunch</strong> to update Chrome.</li>
</ol>
</div>
<p class="p">This section covers the following topics:</p>
<ul class="ul" id="topic_rjq_rzz_c1c__ul_pyh_g11_d1c">
<li class="li"><a class="xref" href="#topic_rjq_rzz_c1c__section_mwk_nv2_d1c">Using DSCP
functions correctly</a></li>
<li class="li"><a class="xref" href="#topic_rjq_rzz_c1c__section_slj_mv2_d1c">Checking
DSCP tags for machines on a domain</a></li>
<li class="li"><a class="xref" href="#topic_rjq_rzz_c1c__section_jyy_jv2_d1c">Checking
DSCP tags for machines that are not on a domain</a></li>
<li class="li"><a class="xref" href="#topic_rjq_rzz_c1c__section_otq_hv2_d1c">Requirements for Windows computers</a></li>
</ul>
<div class="section" id="topic_rjq_rzz_c1c__section_mwk_nv2_d1c">
<h4 class="title sectiontitle">Using DSCP functions correctly</h4>
<p class="p">In some Windows-based environments, DSCP tags are filtered out despite the
network being set up for DSCP. Your network team can verify if DSCP tags are
being filtered out by Windows by running a capture in <a class="xref" href="https://www.wireshark.org/" target="_blank">Wireshark</a>. Either implement a group policy that enforces DSCP
or, if your computers are not on a domain, implement it on a
computer-by-computer basis.</p>
</div>
<div class="section" id="topic_rjq_rzz_c1c__section_slj_mv2_d1c">
<h4 class="title sectiontitle">Checking DSCP tags for machines on a domain</h4>
<p class="p">For machines on a domain, you control the QoS settings that are used for
certain applications by designing different Group Policy rules.</p>
<p class="p">You must force client machines to pick up new Group Policy rules to make the
Dialer work at its best (usually a reboot is enough). To make the Dialer
work optimally, use the following steps to ensure that WebRTC packets are
prioritized.</p>
<p class="p"><strong class="ph b">To check DSCP tags for machines on a domain</strong></p>
<ol class="ol" id="topic_rjq_rzz_c1c__ol_qhy_q3g_d1c">
<li class="li">In your command line, enter gpedit.msc to open the Group Policy
rules.</li>
<li class="li">In <strong class="ph b">Group Policy rules</strong>, under <strong class="ph b">Computer Configuration</strong>,
select <strong class="ph b">Policy Based QoS Settings</strong>.</li>
<li class="li">Right-click, then select <strong class="ph b">Create new Policy</strong>.<p class="p">A wizard interface
opens to configure the QoS rules.</p>
</li>
<li class="li">In <strong class="ph b">Policy name</strong>, enter Salesloft DSCP. For the DSCP value, enter
46.</li>
<li class="li">Click <strong class="ph b">Next</strong>.</li>
<li class="li">In the next dialog, select <strong class="ph b">Only applications with executable
name</strong>, then enter Chrome.exe</li>
<li class="li">Click <strong class="ph b">Next</strong>.</li>
<li class="li">In the dialog, click <strong class="ph b">Next</strong> (you do not need to enter any
settings).</li>
<li class="li">In the next dialog, select the protocol that the QoS applies to. For the
Salesloft Dialer, this is limited to UDP.</li>
</ol>
</div>
<div class="section" id="topic_rjq_rzz_c1c__section_jyy_jv2_d1c">
<h4 class="title sectiontitle">Checking DSCP tags for machines that are not on a domain</h4>
<p class="p">This section modifies the registry setting so you can specify the QoS setting
that'll be based on your Group Policy configuration.</p>
<p class="p"><strong class="ph b">To check DSCP tags for a machine not on a domain</strong></p>
<ol class="ol" id="topic_rjq_rzz_c1c__ol_c5n_bk2_sxb">
<li class="li">Navigate to <strong class="ph b">HKEY_LOCAL_MACHINE</strong> &gt; <strong class="ph b">CurrentControlSet</strong> &gt;
<strong class="ph b">Services</strong> &gt; <strong class="ph b">tcpip</strong> &gt; <strong class="ph b">QoS</strong>.</li>
<li class="li">If the QoS key does not exist, right-click <strong class="ph b">TCP/IP</strong> and select
<strong class="ph b">New Key</strong>.</li>
<li class="li">For the name, enter QoS.</li>
<li class="li">Select the <strong class="ph b">QoS</strong> key.</li>
<li class="li">If the string does not already exist, create a new string "Do not use
NLA".</li>
<li class="li">Set the value to 1.</li>
<li class="li">Reboot your computer and the new settings will take effect.</li>
</ol>
</div>
<div class="section" id="topic_rjq_rzz_c1c__section_otq_hv2_d1c">
<h4 class="title sectiontitle">Requirements for Windows computers</h4>
<div class="p">You may encounter issues if your computer uses the Windows operating system.
Using the command prompt, customers must use the Quality Windows Audio
Visual Experience (QWAVE) service and change the startup type to automatic
(as it's set to manual by default).<div class="note note">
<span class="notetitle">Note:</span> You must run the Command Prompt as
an administrator. </div>
</div>
<p class="p"><strong class="ph b">To ensure QWAVE is activated and startup is automatic</strong></p>
<ol class="ol" id="topic_rjq_rzz_c1c__ol_e5n_bk2_sxb">
<li class="li">Open the Windows <strong class="ph b">Start menu</strong>.</li>
<li class="li">In the <strong class="ph b">Search</strong> bar, enter cmd.</li>
<li class="li">Right-click <strong class="ph b">Command Prompt </strong>, then click <strong class="ph b">Run as
administrator</strong>.<p class="p"><img class="image" id="topic_rjq_rzz_c1c__image_f5n_bk2_sxb" src="https://support.zendesk.com/hc/article_attachments/7856503151770"></p>
</li>
<li class="li">Paste the following text into the command
line:<pre class="pre">net start QWAVE </pre>
</li>
<li class="li">Press <strong class="ph b">Enter</strong> to see the following results.<p class="p"><img class="image" height="377" id="topic_rjq_rzz_c1c__image_g5n_bk2_sxb" src="https://support.zendesk.com/hc/article_attachments/7856497648666" width="653"></p>
</li>
<li class="li">To ensure the service startup type is permanently set to automatic,
paste the following code into the command
prompt.<pre class="pre">REG add "HKLM\SYSTEM\CurrentControlSet\services\QWAVE" /v Start /t REG_DWORD /d 2 /f</pre>
</li>
<li class="li">Press <strong class="ph b">Enter</strong>.</li>
</ol>
<p class="p">The QWAVE service has set the startup type to automatic. If you encountered
an error when following the above steps, ask a member of your IT team or a
computer administrator to perform them.</p>
<p class="p"><a class="xref" href="https://docs.microsoft.com/en-us/windows/security/threat-protection/windows-firewall/create-a-group-policy-object" target="_blank">Create a group policy object</a> on
your network to set the service for all client computers to automatic. This
will save you from having to set up each computer manually.</p>
</div>
</div>
</div>
</div>
<div aria-labelledby="ariaid-title6" class="topic nested1" id="topic_ptb_5j2_sxb">
<h2 class="title topictitle2" id="ariaid-title6">Troubleshooting</h2>
<div class="body">
<div class="section" id="topic_ptb_5j2_sxb__section_ccs_pbl_sxb">
<h3 class="title sectiontitle">Call quality and connectivity problems</h3>
<p class="p">If you're experiencing connectivity or audio problems, it could be related to
your network configuration or installed software that is designed to monitor and
block IP connections. This includes, for example, firewalls, anti malware,
antivirus programs, intrusion prevention systems (IPS), intrusion detection
systems (IDS), web application firewalls (WAFs), web filters, and ad
blockers.</p>
<p class="p">The following tests will help you troubleshoot most audio and connectivity
problems.</p>
<div class="p">
<ul class="ul" id="topic_ptb_5j2_sxb__ul_igx_z4g_d1c">
<li class="li">
<strong class="ph b">Disable any interfering software</strong>: Temporarily disable any
software that can monitor and block IP connections. Such software
includes firewalls and antivirus software, web filters, and ad-blockers.
This helps determine if they are what's causing connectivity issues.
Make new test calls and reassess the situation. To keep your system
secure, always remember to reactivate your security software after
you've completed testing.</li>
<li class="li">
<strong class="ph b">Unrestrict internet access</strong>: Ensure your computer has unrestricted
internet access for connectivity tests, then make new test calls and
reassess the situation. A stable and high-quality internet connection is
essential for seamless VoIP calls.</li>
<li class="li">
<strong class="ph b"><a class="xref" href="https://networktest.twilio.com/?usenewvoiceips=true" target="_blank">Run a Twilio WebRTC
Diagnostics</a> test:</strong> Run a diagnostics test before, and
immediately after, making any network changes. Comparing the before and
after test results can give you a clearer indication of where the issue
is originating from. If you're unsure of how to interpret the results,
see <a class="xref" href="https://support.zendesk.com/hc/en-us/articles/4408823183002" target="_blank">How do I use the Twilio network test
to troubleshoot agent calls</a>. It explains the test results
line by line.</li>
</ul>
</div>
<p class="p">By carrying out the above tests, you can identify whether the call issues are
coming from specific areas, such as network configurations, or from software
that is blocking the connection.</p>
<p class="p">For more troubleshooting help, see <a class="xref" href="https://support.zendesk.com/hc/en-us/articles/4408829651738" target="_blank">How can I troubleshoot voice
issues?</a></p>
</div>
<div class="section" id="topic_ptb_5j2_sxb__section_nrc_mbl_sxb">
<h3 class="title sectiontitle">Error message: Some voice features aren't available</h3>
<p class="p">You may receive the following error message: "Some features aren’t available
right now. You can still make and receive calls." This message means either your
browser or your computer cannot connect to the required URLs. If you don’t allow
communication, then you will only be able to accept or decline calls and hang
up. Multiple features will not work, including the following:</p>
<div class="p">
<ul class="ul">
<li class="li">Wrap up<div class="note note">
<span class="notetitle">Note:</span> If Wrap up is activated, the user will be immediately
dropped from the call.</div>
</li>
<li class="li">Recording</li>
<li class="li">Transfers</li>
<li class="li">Hold</li>
</ul>
</div>
<p class="p"><strong class="ph b">To resolve this error </strong></p>
<div class="p">
<ol class="ol" id="topic_ptb_5j2_sxb__ol_izc_w4s_sxb">
<li class="li">Contact your network administrator to activate your network to
communicate with your computer or browser.</li>
<li class="li">Follow the steps in <a class="xref" href="https://support.zendesk.com/hc/en-us/articles/4408825035674-Troubleshooting-agent-collision-in-Play-mode#:~:text=to%20do%20this.-,Agent%20Presence%20URLs,-Connections%20to%20Zendesk" target="_blank">Troubleshooting agent collision in
Play mode</a>.</li>
</ol>
</div>
</div>
</div>
</div>
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