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Cisco Webex Contact Center Voice POP Bridge (vPOP) Onboarding Guide
This article provides a detailed information about onboarding Cisco Webex Contact Center using the Voice POP Bridge (vPOP), a legacy method for connecting traditional phone networks (PSTN) for inbound and outbound calls.
Provision Voice for Cisco Webex Contact Center
Overview
Customer enterprises can use a Cisco Unified Border Element (CUBE) as the session border controller (SBC) to connect to Webex Contact Center. The enterprise CUBE connects to a carrier for PSTN or VoIP connectivity on one side and to Webex Contact Center on the other side to enable contact center services. Both inbound and outbound calls to Webex Contact Center route through the enterprise CUBE. The customer provides the SIP trunk, activated bidirectionally to the service provider and Webex Contact Center, to enable the call traffic between the platforms. For more information about CUBE, see the Cisco Unified Border Element Configuration Guide in https://www.cisco.com/c/en/us/support/unified-communications/unified-border-element/products-installation-and-configuration-guides-list.html.
Either the service provider or the customer enterprise can own and operate the CUBE and the Private Branch Exchange (PBX). In this case:
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All inbound calls to Webex Contact Center come through the carrier at the enterprise CUBE.
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Webex Contact Center sends all outbound calls, whether to customers or agents, through the enterprise CUBE.
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Webex Contact Center works with the service provider to bill the customer directly for PSTN usage, without going through Webex Contact Center billing.
Webex Contact Center supports CUBE, Virtual CUBE (vCUBE), and third-party SBC.
When the service provider owns the SBC and PBX, Webex Contact Center provides a SIP header to identify the customer enterprise to the service provider. Service providers configure the specific SIP header through the Application Service Provider dashboard.
Webex Contact Center supports these SIP headers:
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Diversion
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PAI
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OTG
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DTG
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TGRP
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RPID
The customer enterprise may own and operate the CUBE and the PBX, which eliminates the need for a SIP header.
Audience
This document is intended for users who use Cisco Webex Contact Center.
Change History
This table lists changes made to this guide after the initial release. The most recent changes appear at the top.
Change |
See |
Date |
---|---|---|
New deployment figures |
October 2021 | |
New section |
October 2021 | |
Multiregion Support |
September 2021 | |
New section |
September 2021 | |
Document restructure |
Several chapters were restructured. |
August 2021 |
Included a new chapter | Types of Connectivity |
July 2019 December 2020 |
Multiregion Support
Webex Contact Center with Webex Calling Telephony supports multiple regions (either countries or regions) for the agents and callers. We support the following scenarios:
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Callers are located one region and agents are located in multiple regions.
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Callers and agents are located in multiple regions.
In these scenarios, the system provides inbound-call and outdial-call support. For inbound calls, the callers call to the Cloud-Connected PSTN (Cisco Webex cloud) or the Local Gateway (LGW) setup. The calls route to the agents. Agents can make outdial calls to any region.
The agents belong to different locations as configured in Control Hub. The agent's configuration has the number and extension for their location.
Inbound numbers are associated with the regions in Control Hub. Calls route to the agents according to the routing strategy configured in Webex Contact Center.
The following figure shows a global solution for Webex Contact Center with Webex Calling.
Media such as IVR and call recording reside in the Home Region. Agents across the globe can have Webex Calling phones or endpoints behind the Local Gateway deployment options.
The location of the Home Region requires careful consideration to minimize the distance between the regions, the callers, and the agents. The following figure shows the call path for agents and callers in a region that is remote from the Home Region. In this scenario, the distance between the Home Region and the Remote Region can introduce unacceptable latency in the call.
Callers Are in One Region and Agents Are in Multiple Regions
In this scenario, the Webex Contact Center has agents in different regions and associated with several data centers. The callers are from a single region.
The callers call the Webex Contact Center. The system routes their calls to the contact center and, based on time-of-day configuration, routes the calls to available agents in one of the regions.
To support this scenario:
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The Webex Contact Center uses Webex Calling (VPOP Bridge or LGW).
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If the agent endpoint is on a BYoPSTN, the call is a local call from the voice platform for the agent’s region.
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If the agent endpoint is a Cisco IP Phone or the Webex Calling app, the call may be local for the agent’s region.
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The agent desktop URL is in the same region as the agent.
This scenario is for an inbound voice call, but the system supports similar scenarios for outdial calls.
Callers and Agents Are in Multiple Regions
In this scenario, the contact center has agents in multiple regions and associated with several data centers. The callers are from multiple regions.
The callers call the contact center. The system routes their calls to the contact center and, based on time-of-day configuration, routes the calls to available agents in one of the regions.
To support this scenario:
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The contact center uses Webex Calling (VPOP Bridge or LGW).
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If the agent endpoint is on a BYoPSTN, the call is a local call from the voice platform for the agent’s region.
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If the agent endpoint is an IP-Connected device, the call may be local from the voice platform for the agent’s region.
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The agent desktop URL is in the same region as the agent.
This scenario is for an inbound voice call, but the system supports similar scenarios for outdial calls.
Related Documentation
To view the list of Webex Contact Center documentation, see https://www.cisco.com/c/en/us/support/customer-collaboration/webex-contact-center/series.html.
To view Webex Contact Center developer documentation and API references, see https://developer.webex-cx.com/documentation/getting-started.
Conventions
This guide uses the following conventions.
Convention |
Description |
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Boldface font |
Text in a boldface font indicates commands, such as user entries, keys, buttons, and submenu names. For example:
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Italic font |
Text in an italic font indicates the following:
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Text in a Window font, such as Courier, indicates the following:
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To find warranty information for a specific product or product family, access Cisco Warranty Finder.
Cisco Bug Search Tool
Cisco Bug Search Tool (BST) provides web-based access to the Cisco bug tracking system. This system maintains a comprehensive list of defects and vulnerabilities in Cisco products and software. BST provides you with detailed defect information about your products and software.
Documentation Feedback
Provide your comments about this guide to the contactcenterproducts_docfeedback@cisco.com site.
Webex Contact Center Call Flow
Call Flow Introduction
Inbound and outbound calls to Webex Contact Center come through a carrier, which is routed through the Enterprise and Cisco Unified Border Element (CUBE). Every call can include multiple sessions, depending on the call flow. The following sections describe some typical call flows.
Inbound Call to an IVR
An inbound call from the caller to the Webex Contact Center Voice Post Office Protocol (VPOP) creates a single session in the enterprise CUBE and a single session in the Webex Contact Center CUBE.
Inbound Call to an Agent
An inbound call to an agent adds an outbound session in the Webex Contact Center CUBE and a single session in the enterprise CUBE.
Conference and Consult Transfer
An agent-to-agent conference or consult transfer adds an outbound session in the Webex Contact Center and the enterprise CUBE.
Callback or Outbound Call to PSTN
An outbound call creates two sessions, one from the Enterprise tenant to Webex Contact Center and another from Webex Contact Center to the Enterprise.
CUBE License and Sizing Requirements
CUBE Licenses
Cisco Unified Border Element (CUBE) licenses apply per session and require a two-way session. For more information, see Cisco Unified Border Element Data Sheet.
CUBE license sizing is the sum of the number of agent sessions and the number of calls at the Interactive Voice Response (IVR). Use the Cisco Unified Border Element Data Sheet to determine the maximum number of sessions that your CUBE platform supports.
The number of licenses must be equal to the maximum capacity of the customer enterprise.
licenses = (number of agents X 2) + (number of active sessions in queue)
Example
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At peak time if you have 100 agents responding to customer calls, each call has two active sessions. The number of sessions is 200.
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The number of calls in the queue in this instance is 100, which creates 100 sessions.
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Therefore, the total number of sessions equals 300, which is 300 licenses.
CUBE Session Size
A CUBE device can handle 1/3 of the SIP sessions, if you secure the calls with either TLS or SRTP.
sessions = ((number of agents X 2) + (number of active sessions in queue)) X 3
Using the example of 100 calls in a queue with 100 agents responding to calls, the number of sessions is:
((100 X 2)+ 100) X 3 = 900
.
You can size the CUBE for 300 sessions if you provision a private WAN for the SIP Trunk.
To help determine the maximum number of agents, assume that:
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50% of the calls are queued and use IVR ports, while the remaining 50% of calls are active with agents.
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10% of the calls use the consult and conference-supplementary services.
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TLS or SRTP secure 100% of the calls.
Using these assumptions, CUBE platforms can support one agent for every 9.3 sessions.
Types of Connectivity
Supported Connectivity Types
Webex Contact Center supports the following types of connectivity.
Connectivity |
Types |
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Public Internet |
Direct IPSec Virtual Private Network (VPN) or IPSec over Generic Routing Encapsulation (GRE) Site-to-Site (S2S) SRTP/SIP TLS |
Private Connectivity (Approval Required) |
MPLS Point-to-Point (P2P) VPLS SD-WAN Private WAN Data Center Cross-Connect Equinix Fabric Connections |
IOS Version for CUBE or vCUBE should support TLS 1.2.
Public Internet
Direct SIP Trunk (Over the Top)
Cisco recommends that customers place the CUBE or SBC on a public IP address.
Pros |
Cons |
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Because a direct connection is the most simplistic approach, it is also the least flexible. The benefits of a simplified topology are ease of management and troubleshooting. The customer completes the network diagrams and submits them to the Voice team, and dial-peers are created. You can place the CUBE in a DMZ to alleviate the complexities of dealing with Network Access Translation (NAT). The CUBE itself is a firewall, and most providers place their CUBE in a public IP space and use its security capabilities.
VPNs
A VPN is another type of connection that uses the public internet. Use VPNs when a customer requires a secure connection for SIP and RTP. A VPN might also be required if the customer cannot place the CUBE in a public IP space. A provisioning meeting with Voice Engineering is required for VPN connections.
Pros |
Cons |
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Voice Ports
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RTP: 8000–48199
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SIP: UDP 5060
IPSec VPN or IPSec over GRE
The following options are available for VPN Connectivity:
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SBC to SBC connectivity
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GW to GW connectivity
Webex Contact Center (IPSec or IPSec over GRE tunnel, and Webex Contact Center S2S Connectivity) must use UDP/5060 instead of TCP/5060.
An IPSec VPN or IPSec over GRE is a good option for a secure SIP Trunk when the CUBE is on a public IP space. This is an SBC to SBC connection with VPN tunnels. You must also consider private IP address schemes to avoid any overlap between customers. For GRE connections, IP subnets are 10.x.248.x and 10.x.249.x.
Site-to-Site (S2S)
A S2S connection can be deployed if the customer needs a secure connection or cannot place the CUBE in a public IP space. This is a gateway to gateway connection. There are no subnets specifically designated for S2S VPN connections as routing is based on interesting traffic without the involvement of a logical interface.
SIP TLS and SRTP
SRTP/SIP TLS is another option when the CUBE is on a public IP address. However, there is a performance hit wit SRTP/SIP TLS. A CUBE device can handle one-third of the SIP sessions if you have secured the calls using either TLS or SRTP. This is a SBC to SBC connection.
Public and Self-Signed Certificates
In order to establish a SIP TLS connection, it is necessary to exchange certificates. The following options are available:
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Self-signed certificates are generated and exchanged between the customer and Webex Contact Center.
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Public CA—Complete the following steps to support a Public CA:
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Customer shares the root certificate, which is loaded into the Webex Contact Center SBC.
You must provide both root and intermediate/subordinate certificate.
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Customer updates the DNS to include the IP addresses of the Webex Contact Center SBCs.
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Private Connectivity
Large enterprise providers often prefer a direct connection because it provides a dedicated and secure circuit. If the customer needs a direct connection, provide them with the Cisco Webex Contact Center VPOP Circuit Order Guidelines as the initial step. The next step is a follow-up design meeting with the Webex Contact Center Voice Engineering team and the customer engineers. The customer provides a detailed network diagram of the customer's voice network, including PSTN carrier interconnects, for the meeting. Cisco won't host any customer equipment.
Cisco Webex Contact Center also offers Equinix Fabric connections for customers who have collocations with Equinix.
For more information on Equinix Fabric, see:
Irrespective of whether the customer chooses MPLS, P2P, VPLS, or SD-WAN, the topology looks similar and all circuits end in the Webex Contact Center router/GW (gateway) and not in Webex Contact Center CUBEs.
The bandwidth requirements for a direct connect are based on the G.711 codec (~100 kbps per call leg), which allows for two call legs per session.
Pros |
Cons |
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Equinix Fabric connections offer port redundancy, faster virtual connection ordering, and provisioning. Cisco recommends using Equinix connection, rather than using other private connection methods.
Data Center Cross Connect
If a customer decides to use a private connection, you must order data center cross connects as described in the Cisco Webex Contact Center VPOP Circuit Order Guidelines. The customer is responsible for the cost that is incurred, and for getting the customer's circuit to the designated drop.
Customers who opt for a private connection receive the Cisco Webex Contact Center VPOP Circuit Order Guidelines during the onboarding process.
Non-Standard Deployments
Non-Standard Deployments
If the recommended topologies do not meet all the requirements of the customer's network, a design meeting must be scheduled with the Cisco Voice Engineering team via the customer's Cisco account team for a special approval process. The following sections are examples of non-standard deployments and deployments that are not recommended:
A2Q Exceptions
PSTN Provider terminating the circuit directly to Webex Contact Center VPOP.
Gold Tenant Exceptions
Cisco strongly recommends a direct SIP Trunk for Gold Tenant customers. This is the over-the-top topology of placing the CUBE in a public IP space. The need for a Gold Tenant often exists with larger providers; however, the provider requires the Gold Tenant to be a proof of concept for the provider's intended production deployment. The proof of concept Gold Tenant often exceeds using open internet access for a SIP Trunk and would require one of the previously discussed connection types.
Gold Tenant customers will not be monitored.
Public Internet – CUBE Behind Firewall
Placing a CUBE on a private IP address behind a NAT firewall is another deployment option. The security requirements from the customer’s IT department can stipulate that the voice application reside behind a firewall. This option has a few known drawbacks. Even though this may not cause issues in the network layer, it may result in issues in the SIP application layer. The private IP address is used within the SIP messages, which causes call processing failures. Firewall capacity is another factor to be considered for this type of deployment. Firewalls must be sized appropriately to handle VoIP traffic; the firewall may otherwise become a bottleneck and can impact call quality and call processing.
The following are the disadvantages of this deployment:
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Possible CUBE configuration and setup issues at the beginning.
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Increased load on firewall that could impact voice quality.
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The customer is responsible for CUBE setup and firewall sizing.
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Not a recommended topology due to impact on SLAs.
This topology is not recommended due to the complexities of dealing with SIP and NAT. A meeting with the Cisco Voice Engineering team and the customer is required for approval of this type of deployment.
Component Redundancy
Component Redundancy Introduction
Component redundancy allows Webex Contact Center to provide resilience when there is a service outage. You can configure both Webex Contact Center cloud and enterprise CUBE to be redundant:
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Within a geographic region—You can set up more than one POP within an enterprise.
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Across enterprise data centers within a geographic region.
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Within enterprise networks—You can also set up CUBE in high availability (HA) mode. HA mode preserves oth signaling and media.
All signaling and media are sourced to and from the virtual IP address.
Webex Contact Center uses two VPOPs to ensure high availability. For optimal performance, the service provider should also set up two POPs. This ensures that the hunting between the Webex Contact Center VPOPs is an even round robin.
Redundancy Across Enterprise Data Centers Within a Geographic Region
You can configure two data centers within the enterprise to connect to the same Webex Contact Center VPOP, within the same geographic region.
Enterprise CUBE to Webex Contact Center Configuration Example
Enter Global Configuration Mode
This configuration example applies to the Cisco IOS Voice Gateway and the Cisco Unified Border Element (CUBE) Voice gateway. For complete CUBE configuration instructions, see the Cisco Unified Border Element Configuration Guide in https://www.cisco.com/c/en/us/support/unified-communications/unified-border-element/products-installation-and-configuration-guides-list.html. All configurations in this example use global configuration mode.
1 |
Enter |
2 |
Enter |
Basic Configuration
SIP Timers (MIN-SE) are set to 3600 across all VPOPs in Webex Contact Center. You can update this setting globally or modify it in the Invite to the Webex Contact Center.
voice service voip
Sip
Min-se 3600
Configure Voice Codec Class
voice class codec 100
codec preference 1 g711alaw
codec preference 2 g711ulaw
Inbound Dial-Peer for Calls from Webex Contact Center
dial-peer voice 200 voip
session protocol sipv2
voice-class codec 100
dtmf-relay rtp-nte
no vad
Outbound Dial-Peer for Calls to Webex Contact Center
dial-peer voice 100 voip
destination-pattern <Pattern towards Webex CC>
session protocol sipv2
session target ipv4:<Webex CC SBC IPs>
voice-class codec 100
voice-class sip options-keepalive
dtmf-relay rtp-nte
no vad
Common Configuration
This example shows Webex Contact Center trunk provisioning in the USA with the following topology.
Setup details:
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Configure SIP Keepalive Options.
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New dial peers with target destination IP address Webex CC LAX and JFK CUBEs.
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Dial-peer preference can be either setup to round robin, or primary and secondary.
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Codec is set up for G711 ulaw and G711 alaw (connections outside US). DTMF is RFC2833.
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SIP Communication is over UDP port 5060 and RTP ports 8000 to 48199.
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Dial plan where the destination pattern matches Webex Contact Center to agents through PBX and PSTN.
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More than one POP for high availability.
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MIN SE timer on Webex CC is 3600; session timers should either be updated to this value or should allow SIP negotiation to this value during a call setup.
If you are using CUBE/vCUBE, Cisco recommends that you use an IOS version which supports TLS 1.2.
Secure SIP Trunk Between CUBE and Webex Contact Center
Secure SIP Trunk Overview
This example demonstrates how to configure a SIP Transport Layer Security (TLS) connection between Cisco Unified Border Element (CUBE) and Webex Contact Center.
Example: Configure SIP TLS
Before you begin
Ensure that:
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The endpoints have the same date and time. You can synchronize endpoints by using a Network Time Protocol (NTP) server.
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You have TCP connectivity.
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The CUBE has the security and UCK9 licenses installed.
1 |
Create a trustpoint to hold the self-signed certificate of the CUBE:
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2 |
Generate a self-signed certificate:
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3 |
Export the certificate:
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4 |
Copy the self-signed certificate that you exported and save it as a text file with the |
5 |
Upload the self-signed CUBE certificate to Webex Contact Center. |
6 |
Copy the certificate from Webex Contact Center. |
7 |
Upload the Webex Contact Center certificate to CUBE:
Enter |
8 |
Configure SIP to use the self-signed certificate trustpoint that you created in step 1:
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9 |
Configure the dial peers with transport layer security:
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Configure a SIP Trunk for Your Tenant
Before You Configure
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Ensure that you have the Gold partner tenant and access to the Service Provider Portal.
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Configure the enterprise session border controller.
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Obtain a destination address for your SIP Trunk.
For more information, see the Cisco Unified Border Element Configuration Guide in https://www.cisco.com/c/en/us/support/unified-communications/unified-border-element/products-installation-and-configuration-guides-list.html.
Provision Your Tenant
Cisco uses the provisioning information that you provide to configure the Webex Contact Center session border controller for your tenant. Make sure that the information you provide matches your order, and is accurate.
For instructions on how to provision your tenant, see the administration and user guides at:
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Configure a SIP trunk that connects your customer's IP address to the configured border controller. Make sure that you select
CUBE
as your SIP Trunk Type. Configure a SIP trunk for each CUBE that you deploy. -
Create and provision a tenant.
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Assign SIP trunk to the tenant, add dial numbers, and provision your new tenant.
After you provision the tenant and configure the Webex Contact Center CUBE, you receive an email that the tenant is ready for use.
Webex Contact Center Regions
VPOP is available for tenant connection by region:
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US: Los Angeles and New York
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Europe: London, Amsterdam, Frankfurt
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Canada: Toronto and Vancouver
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Australia: Sydney and Melbourne
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Japan: Tokyo and Osaka
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South America: São Paulo and Rio de Janeiro
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Singapore
Webex Contact Center Glossary
Glossary
Acronym or Term |
Description |
---|---|
A2Q |
Assurance to Quality |
ACD |
Automatic call distribution |
ADA |
Webex Contact Center Agent Desktop Application |
ADR |
Agent Detail Report |
AES |
Advanced Encryption Standard |
ANI |
Automatic Number Identification |
API |
Application Programming Interface |
BST |
Cisco Bug Search Tool |
BYoPSTN |
Bring Your Own PSTN Customer (enterprise) owned existing premise-based PSTN. |
CA |
Certificate Authority |
CAD |
Call-associated data |
CC |
Contact Center |
CCDR |
Cumulative call detail records |
CCG |
Computer Communications Group |
CCP |
Cloud-Connected PSTN |
CDR |
Call detail records |
CSS |
Contact Selection Strategy |
CSV |
Comma-separated values |
CTQ |
Consult-to-queue |
CUBE |
Cisco Unified Border Element |
DID |
Direct Inward Dial |
DMZ |
Demilitarized zone |
DN |
Directory Number |
DNC |
Do Not Call |
DNIS |
Dialed number identification service |
DNS |
Domain Name System |
DTG |
(SIP Header) Destination Trunk Group |
DTMF |
Dual-Tone Multi-Frequency |
EP |
Entry point |
ESR |
Extended Support Release |
FIPS |
Federal Information Processing Standards |
GIF |
Graphics Interchange Format |
GRE |
Generic Routing Encapsulation |
GW |
Gateway |
HA |
High Availability |
HTML |
Hypertext Markup Language |
IB |
Inward Bound |
ID |
Identity, Identification |
IMAP |
Internet Message Access Protocol |
IOS |
Mobile operating system (formerly iPhone OS) |
IP |
Internet Protocol |
IPsec |
Internet Protocol Security |
ITSP |
Internet telephony service provider |
IVR |
Interactive Voice Response |
JPG and JPEG |
Joint Photographic Experts Group A digital image file |
LAN |
Local Area Network |
LCM |
List and Campaign Manager |
LGW |
Local Gateway |
MPLS |
Multiprotocol Label Switching |
NAT |
Network Access Translation |
NDC |
Network Data Collection |
NTP |
Network Time Protocol |
OB |
Outward Bound |
OTG |
(SIP Header) Originating Trunk Group |
P2P |
Point to Point |
PAI |
(SIP Header) P-asserted identity |
PBX |
Private Branch Exchange |
PCI DSS |
Payment Card Industry Data Security Standard |
|
Portable Document Format |
PEWC |
Prior express written consent |
PII |
Personally identifiable information |
PNG |
Portable Network Graphic |
POP |
Post Office Protocol |
PSTN |
Public Switched Telephone Network |
QoS |
Quality of Service |
RFC |
Request for Comments |
RONA |
Redirect On No Answer |
RPID |
(SIP Header) Remote Party ID |
RTT |
Round Trip Time |
S2S |
Site-to-Site |
SBC |
Session border controller |
SBR |
Skills-Based Routing |
SD-WAN |
Software-defined Wide Area Network |
SIP |
Session Internet Protocol |
SL |
Service level |
SLA |
Service level agreement |
SMS |
Short message service |
SMTP |
Simple Mail Transfer Protocol |
SP |
Service Provider |
SRTP |
Secure Real-time Transport Protocol |
SSL |
Secure Sockets Layer |
TCP |
Transmission Control Protocol |
TGRP |
(SIP Header) Trunk Group Routing Protocol |
TLS |
Transport Layer Security |
UDP |
User Datagram Protocol |
UI |
User Interface |
URI |
Uniform Resource Identifier |
URL |
Uniform Resource Locator |
UTC |
Universal Time Clock |
vCube |
Virtual CUBE |
VoIP |
Voice over IP |
VPLS |
Virtual private LAN service |
VPN |
Virtual Private Network |
VPOP |
Voice point of presence In Webex Contact Center 1.0, VPOP integrates Webex Contact Center to the PSTN and the first connectivity point for customers. It also has media server for treatment and call recording. |
VPOP Bridge |
Voice point of presence bridge In Webex Contact Center, VPOP Bridge connects the Service Provider's PSTN to the Voice Media Layer. |
WAN |
Wide area network |
WCB |
Word Command Buffer |
Webex CC |
Webex Contact Center |
WFO |
Workforce Optimization |
XML |
Extended Markup Language |