# Using Unified CM phones as Webex Contact Center agent stations

Systems: Webex Contact Center

For Unified CM and Webex Contact Center administrators who already have a Webex Contact Center tenant and a Webex Calling PSTN option, and who need to decide where agents take calls.

Canonical: https://warmtransfer.net/guides/wxcc-cucm-agent-station-setup

Last verified: 2026-10-01

Webex Contact Center agents can use a telephony device connected to a PBX such as Cisco Unified Communications Manager, and agents on a premise-based PBX select Dial Number at sign-in, a destination that must be reachable through Webex PSTN and routing[^42][^44][^18]. The alternatives are Extension, which Webex Contact Center attempts to match with a registered Webex Calling endpoint to enable phone control features, and Desktop, which gives agents WebRTC-based calling directly from the browser[^28][^11].

## Before you start

Cisco advises configuring and validating Webex Calling components, including PSTN connectivity and agent endpoints, before configuring the Webex Contact Center tenant, and states that this significantly accelerates and simplifies the deployment[^64]. WarmTransfer's reading of the sources is that checking Service Details before any other configuration avoids building locations and entry points on a tenant that Cisco must first reprovision, because the tenant's telephony selection is locked after activation[^65].

The voice channel article lists 4 PSTN options for Webex Contact Center: Webex Contact Center PSTN, Webex Cloud Connected PSTN, Cisco Calling Plan and Webex Calling Local Gateway[^66]. A Webex Calling Local Gateway lets a customer retain its current on-premises PSTN carrier, with third-party session border controllers supported alongside Cisco CUBE[^67]. Numbers provisioned through Webex Calling Cloud Connected PSTN are stored in plus-E.164 format[^68].

With Dedicated Instance, Cisco documents an option that places agent phones on Webex Calling multi-tenant with back-office users in Dedicated Instance, connected by the default inter-op SIP trunk, and another that configures agent phones directly in Dedicated Instance with PSTN through a Dedicated Instance Local Gateway or Cloud Connected PSTN in multi-tenant[^17][^16].

Webex Calling Customer Assist is an elevated Webex Calling Call Queue rather than a separate contact centre, with agents and supervisors working from the Webex App[^69].

- The station each agent will use, matching the Handle calls using choices of Desktop, Extension or Dial Number[^46].
- For Unified CM agents, each agent's full number, because Dial Number sign-in with the International dialing format checkbox takes + country code and number[^47].
- The expected peak of concurrent calls, because a registration-based Webex Calling Local Gateway processes up to 250 concurrent calls into Webex Contact Center, counting IVR and agent legs[^70].
- The contact center numbers, which a Local Gateway deployment provisions in Control Hub in +E.164 format[^36].

See also [Webex Calling with Webex Contact Center](https://warmtransfer.net/knowledge/webex-calling-with-webex-contact-center) and [Webex calling PSTN connectivity options](https://warmtransfer.net/knowledge/webex-calling-pstn-connectivity-options).

See also [Cisco Unified CM](https://warmtransfer.net/knowledge/cisco-unified-cm) and [Using the Webex Contact Center Agent Desktop](https://warmtransfer.net/knowledge/webex-cc-agent-desktop-user-guide).

## What changes by situation

- Where does the agent answer contact center calls? A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in; A Webex Calling device or Webex App, reached with Extension sign-in; The Agent Desktop browser softphone (Desktop / WebRTC).
- If agents answer on Unified CM phones, which path carries the agent leg to Unified CM? (Readers on other stations may pick any value.) On-premises Unified CM behind a Local Gateway registered to Webex Calling; Unified CM in Webex Calling Dedicated Instance, with PSTN on a Dedicated Instance Local Gateway; Unified CM in Webex Calling Dedicated Instance, with Cloud Connected PSTN in multi-tenant.

## Step 1: Prove the PSTN path before touching contact center settings

### Do

Make successful inbound and outbound calls over your chosen Webex Calling PSTN connectivity option before you complete the remaining Webex Contact Center voice tasks, as Cisco advises[^48]. Set each Webex Calling location's PSTN connection on its Calling tab to Cisco PSTN, Cloud Connected PSTN or Premises-based PSTN through a Local Gateway[^71]. For a Local Gateway, provision the DID and toll-free numbers in Control Hub in +E.164 format[^36]. Run Cisco IOS XE 17.6.1a or later on a registration-based Local Gateway, or 17.9.1a or later on a certificate-based one[^35].

### Verify

Suggested check: place one inbound and one outbound call over the PSTN path and confirm two-way audio on both.

Suggested check: confirm every contact center number appears in international format with a leading plus sign.

### Rollback

Suggested rollback: return any location whose PSTN connection you changed to its previous setting.

## Step 2: Align codec, DTMF and offer model on every hop

### Do

Webex Contact Center accepts only G.711 u-law or A-law on PSTN legs and does not transcode, so transcode any G.729, iLBC or Opus leg before it reaches Webex Contact Center[^29]. Carry DTMF as RFC 2833, which Webex Contact Center requires on PSTN legs[^26]. Use SIP Delayed Offer, because Webex Contact Center does not support SIP Early Offer[^10]. Do not rely on SIP Early Media, which Webex Contact Center does not support on PSTN legs[^41]. Cisco describes SIP Early Offer and SIP Early Media as roadmap items[^72]. On a Local Gateway, Cisco's example configures voice class codec 100 to allow only G.711 codecs on all trunks[^34].

### Verify

Suggested check: inspect the session description on a test call and confirm that only the codec you allowed is negotiated.

Suggested check: navigate a keypad menu on a test call and confirm each keypress is recognised.

### Rollback

Suggested rollback: restore the previous codec class and SIP profile settings on each hop.

## Step 3: Map the contact center number to an entry point

### Do

Check the numbers under Calling > Numbers, then create the inbound entry point under Services > Contact Center > Customer Experience > Channels by selecting the Webex Calling PSTN number and its Webex Calling location[^27]. Choose channel type Inbound Telephony and select a routing flow; the timezone defaults to the tenant timezone[^73]. A Webex Calling location's main number does not appear in the list of numbers available for entry point mapping, so using it requires changing the location's main number[^74]. System limits allow 500 dialed numbers per entry point and 15,000 dialed numbers configured as entry points in total[^75].

### Verify

Suggested check: call the contact center number from an outside phone and confirm the call enters the entry point's flow.

### Rollback

Suggested rollback: unmap the number from the entry point, or delete the entry point if you created it only for this work.

## Step 4: Build the agent leg

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in + On-premises Unified CM behind a Local Gateway registered to Webex Calling**

### Do
In Control Hub, add the Local Gateway trunk under Calling > Call Routing > Trunk as Registration based or Certificate Based; Certificate Based is required for deployments needing more than 250 concurrent calls[^39]. Cisco counts IVR and agent legs toward that 250-call threshold[^70]. Create a route group under Calling > Call Routing > Route Group with the trunk assigned, and set the location to Premise-Based PSTN under Locations > Calling[^38]. In Cisco's Local Gateway with Unified CM design, calls from Unified CM to the gateway on port 5060 go to the PSTN and calls on port 5065 go to Webex Calling[^40]. In that design, the incoming dial-peer from Webex (100) applies dial-peer group 300, whose dial-peer 300 sends the call to the Unified CM Webex trunk, and the reverse direction uses dial-peer group 100[^33]. In Cisco's example, dial-peer 300 reaches Unified CM through a DNS SRV session target that resolves to multiple Unified CM nodes[^32]. In Unified CM, configure a SIP profile, then a SIP trunk security profile, then the SIP trunk that applies both[^51]. Set the incoming port in the Webex Calling trunk's SIP Trunk Security Profile to 5065, so that Unified CM accepts messages on that port and puts it in the Via header toward the Local Gateway[^53].
### Verify
Suggested check: confirm the new trunk shows as active in the cloud administration portal.

Suggested check: capture signalling on the gateway while placing one internal call to a cloud user and one PSTN call, and confirm each arrives on the port you assigned to it.
### Rollback
Suggested rollback: remove the new call-control trunk and its security profile, remove the added dial-peer group and dial-peer from the gateway, then delete the route group and trunk after removing any dial plan that uses them.

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in + Unified CM in Webex Calling Dedicated Instance, with PSTN on a Dedicated Instance Local Gateway**

### Do
Use certificate-based (mTLS) trunks, because Cisco states registration-based trunks are no longer supported for the Dedicated Instance contact center integration[^15]. Route the inbound contact center number to multi-tenant over the inter-op SIP trunk[^14]. Cisco directs creating a codec list with G.711 u-law first, then G.711 A-law, then Opus[^13]. Cisco states that this list is built from Factory Default Lossy, is assigned across CTI, endpoint and SIP trunk device pool regions, and must be applied only for the Webex Contact Center integrations[^76].
### Verify
Suggested check: call the contact center number and confirm it reaches the contact center flow instead of ringing an agent phone directly.
### Rollback
Suggested rollback: revert the inbound number routing on the gateway and restore the previous codec list.

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in + Unified CM in Webex Calling Dedicated Instance, with Cloud Connected PSTN in multi-tenant**

### Do
Keep the Cloud Connected PSTN numbers in multi-tenant: the inbound call is routed to Webex Contact Center and then back to the Dedicated Instance agent's phone[^12]. Use certificate-based (mTLS) trunks, because Cisco states registration-based trunks are no longer supported for the Dedicated Instance contact center integration[^15]. Cisco directs creating a codec list with G.711 u-law first, then G.711 A-law, then Opus[^13]. Cisco states that this list is built from Factory Default Lossy, is assigned across CTI, endpoint and SIP trunk device pool regions, and must be applied only for the Webex Contact Center integrations[^76].
### Verify
Suggested check: call the contact center number and confirm it reaches the contact center flow first and then rings the pilot agent's phone.
### Rollback
Suggested rollback: restore the previous codec list.

**A Webex Calling device or Webex App, reached with Extension sign-in**

### Do
Cisco lists 5 supported agent calling devices: a Webex Calling desk phone, the Webex Calling desktop app, the Webex App for mobile, the Webex App integrated with Webex Calling, and the Microsoft Teams softphone[^77]. For Extension sign-in, provision each Webex Calling device with an extension and associate it to the Calling user acting as the agent[^63]. Give each agent who uses a Webex device or the Webex App a valid Webex Calling subscription[^61].
### Verify
Suggested check: confirm each pilot agent's device is registered and associated with the right user.
### Rollback
Suggested rollback: remove the device association from the user.

**The Agent Desktop browser softphone (Desktop / WebRTC)**

### Do
Selecting Desktop as the agent destination lets agents use WebRTC-based calling directly from their browser[^11]. Allow at least 100 kbps of network bandwidth per call[^58]. Use Google Chrome, Microsoft Edge or Mozilla Firefox[^56]. The minimum supported Agent Desktop browsers are Chrome 144+, Microsoft Edge 144+ and Firefox 140+, and Cisco recommends the latest stable versions[^78]. Agent Desktop is supported on VDI, but WebRTC browser-based agent audio is not supported on VDI[^79][^60].
### Verify
Suggested check: confirm every pilot agent meets each of these conditions on the machine and network they will actually use.

## Step 5: Make the agent's destination reachable

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in + On-premises Unified CM behind a Local Gateway registered to Webex Calling**

### Do
A Unified CM partition is a logical group of route patterns, directory numbers and other dialable entries, so place the agent directory numbers in a partition[^80]. A caller can reach a destination only if the destination's partition is in the caller's calling search space[^81]. On the Unified CM SIP trunk facing the Local Gateway, set the Inbound Calls Calling Search Space to a calling search space that contains the agent phones[^52]. WarmTransfer's reading of the sources is that if this inbound calling search space does not include the partition of the agent directory numbers, Webex Contact Center agent-leg calls cannot reach the agent phones[^30]. In Control Hub, create an Outbound Dial Plan under Calling > Call Routing > Dial Plans with a Name, Routing Choice and Patterns to route calls from Webex Contact Center to on-premises agents[^37]. The dial plan must contain a pattern that matches each agent's destination[^20]. Select the previously created trunk or route group as its routing choice[^24]. Patterns can include +E.164 prefixes, SIP URIs or location-specific prefixes[^23]. E.164 patterns start with + and enterprise patterns are digits only; X matches one digit and the exclamation-mark wildcard matches any digit sequence[^25]. The exclamation-mark wildcard may occur only once, only at the end and only in an E.164 pattern, X cannot sit in the middle of a number, and X and the exclamation-mark wildcard cannot be combined[^21]. The dial plan applies to all users regardless of location[^22] and holds up to 10,000 dial patterns[^19].
### Verify
Suggested check: from a test user in the cloud calling service, dial a pilot agent's full international number and confirm the desk phone rings through the gateway.
### Rollback
Suggested rollback: set the trunk's inbound calling search space back to its previous value, then delete the dial plan or remove the added patterns.

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in + Unified CM in Webex Calling Dedicated Instance, with PSTN on a Dedicated Instance Local Gateway**

### Do
A Unified CM partition is a logical group of route patterns, directory numbers and other dialable entries, so place the agent directory numbers in a partition[^80]. A caller can reach a destination only if the destination's partition is in the caller's calling search space[^81]. The agent's Dial Number can be an enterprise DID or a public PSTN number, and it must be reachable through Webex PSTN and routing[^18].
### Verify
Suggested check: from a test user in the cloud calling service, dial the pilot agent's number and confirm the agent's phone rings.
### Rollback
Suggested rollback: remove any partition, calling search space or routing change you added for the agent numbers.

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in + Unified CM in Webex Calling Dedicated Instance, with Cloud Connected PSTN in multi-tenant**

### Do
A Unified CM partition is a logical group of route patterns, directory numbers and other dialable entries, so place the agent directory numbers in a partition[^80]. A caller can reach a destination only if the destination's partition is in the caller's calling search space[^81]. The agent's Dial Number can be an enterprise DID or a public PSTN number, and it must be reachable through Webex PSTN and routing[^18]. That reachability matters here because the inbound call goes to Webex Contact Center first and is then routed back to the Dedicated Instance agent's phone[^12].
### Verify
Suggested check: from a test user in the cloud calling service, dial the pilot agent's number and confirm the agent's phone rings.
### Rollback
Suggested rollback: remove any partition, calling search space or routing change you added for the agent numbers.

**A Webex Calling device or Webex App, reached with Extension sign-in**

### Do
An agent's destination number can be an extension if the agent is a Cisco Webex Calling user[^82]. Webex Contact Center attempts to match the Extension destination with a registered Webex Calling endpoint to enable phone control features[^28]. Managing Webex Calling calls from Agent Desktop requires Webex App 44.12 or later and Webex Calling turned on in Control Hub, and applies when the agent signs in with Dial Number or Extension[^83]. That option is meant only for the Agent persona and does not work correctly for supervisors during monitoring, barge-in or similar scenarios, where the answer button is not available[^84]. As of March 13 2026, agent status is automatically aligned between Webex Calling and Webex Contact Center as part of the CTI connector enhancements[^85].
### Verify
Suggested check: confirm each pilot agent's app meets the minimum version and that an incoming call can be answered from the agent's desktop.
### Rollback
Suggested rollback: turn the desktop call-management option back off.

**The Agent Desktop browser softphone (Desktop / WebRTC)**

### Do
The Desktop (WebRTC) option is currently unavailable for Webex Contact Center customers hosted in the Japan data center[^57]. The Country of Operation chosen in the setup wizard decides which data center hosts the tenant[^86]. Agent Desktop needs at least 4 GB of RAM, and 8 GB or more is recommended[^87].
### Verify
Suggested check: confirm which data center hosts your tenant, and confirm each pilot machine meets the memory requirement.

## Step 6: Allow the right sign-in option in the desktop profile

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in**

### Do
In the agents' desktop profile, enable Agent DN among the voice channel options[^45]. Choose Agent DN validation: Unrestricted lets agents sign in with any DN, and Provisioned DN restricts sign-in to the default DN set in the agent's user settings[^88]. When an administrator configures a Default DN, it is prepopulated in the Dial Number and Extension fields, and where the DN is restricted to that default the fields become read-only[^89]. A saved sign-in preference takes precedence over the configured Default DN[^89].
### Verify
Suggested check: open the sign-in screen as a pilot agent and confirm Dial Number is offered.
### Rollback
Suggested rollback: restore the profile's previous voice channel options.

**A Webex Calling device or Webex App, reached with Extension sign-in**

### Do
In the agents' desktop profile, enable Extension among the voice channel options[^45]. Webex Calling agents can sign in with an +E.164 Dial Number, but then phone control features such as preferred device and answering from Agent Desktop are not available[^62].
### Verify
Suggested check: open the sign-in screen as a pilot agent and confirm Extension is offered.
### Rollback
Suggested rollback: restore the profile's previous voice channel options.

**The Agent Desktop browser softphone (Desktop / WebRTC)**

### Do
In the agents' desktop profile, enable Desktop, which means signing in through a browser using WebRTC[^90].
### Verify
Suggested check: open the sign-in screen as a pilot agent and confirm Desktop is offered.
### Rollback
Suggested rollback: restore the profile's previous voice channel options.

## Step 7: Sign a pilot agent in

**A Cisco Unified CM desk phone or softphone, reached with Dial Number sign-in**

### Do
At sign-in, the agent picks Dial Number from the Handle calls using list, which shows only the options the agent's profile allows[^46]. With the International dialing format checkbox ticked, the agent enters + country code and number; without it, the agent uses E.164 format such as +11234567890 or IDD format[^47]. The International Dialing Format option lets Webex Contact Center route a call destined for a PSTN or premise-based agent using +E.164 addressing[^31].
### Verify
Agents signed in with Dial Number answer incoming contact center calls on their physical phone and use its mute and keypad[^2].

Suggested check: set the pilot agent available, send a test call to the entry point, and confirm the desk phone rings and the agent answers on it.
### Rollback
Suggested rollback: sign the pilot agent out.

**A Webex Calling device or Webex App, reached with Extension sign-in**

### Do
At sign-in, the agent chooses Extension, enters the extension provisioned on the Webex Calling device and clicks Submit[^63].
### Verify
Agents signed in with Extension answer incoming contact center calls on their physical phone and use its mute and keypad[^2].

Suggested check: set the pilot agent available, send a test call to the entry point, and confirm the agent's device rings and the call is answered there.
### Rollback
Suggested rollback: sign the pilot agent out.

**The Agent Desktop browser softphone (Desktop / WebRTC)**

### Do
At sign-in, the agent chooses Desktop, which requires no further input[^91]. Agent Desktop does not currently support headset control actions for WebRTC (Desktop) calls[^59].
### Verify
Suggested check: set the pilot agent available, send a test call to the entry point, and confirm it can be answered in the browser with two-way audio.
### Rollback
Suggested rollback: sign the pilot agent out.

## Step 8: Check what identifies the caller

### Do

In Flow Designer, choose the variables, excluding secure variables, that the Agent Desktop incoming voice call popover shows[^43]. Set the tenant-wide default outdial ANI in Control Hub under Tenant Settings, Voice; a dial number must be mapped to an entry point before it can be chosen[^92]. By default the first dial number mapped to an entry point is shown as the default outdial ANI, and the field reads Not Configured if no dial number is mapped to an entry point[^93]. An agent uses the system-wide default outbound ANI unless a specific default ANI is configured in an Outdial ANI list linked to the agent's desktop profile[^94]. A desktop profile holds an Outdial toggle, an Outdial Entry Point and an Outdial ANI list naming the numbers the agent may present[^95].

### Verify

Suggested check: on a test call, confirm the popover shows the variables you chose, and note which number the agent's phone or app displays for the caller.

Suggested check: place an agent outdial to an outside phone and confirm the presented number is the one you expect.

### Rollback

Suggested rollback: restore the previous popover variables, default outdial number and outdial number list.

## Step 9: Consult and transfer back into Unified CM

### Do

Cisco instructs agents to start hold, resume, consult and transfer from Agent Desktop rather than from a hardphone or softphone[^54]. From Agent Desktop, a voice call can be consulted or transferred to an agent, a queue, a dial number, an entry point or an organization expert[^4]. A dial number entered for consult or transfer can contain 3 to 18 digits plus the special characters +, #, * and:[^3]. The desktop profile Consult to Queue toggle lets agents choose queues as consult targets, and choosing an entry point as the target disables the Consult button[^5].

### Verify

Suggested check: from the agent's desktop, consult a back-office number on the call-control cluster, speak to the consulted party, complete the transfer, and confirm the caller ends up connected to that phone.

### Rollback

Suggested rollback: turn off any desktop profile toggle you enabled for this test.

## Step 10: Run the end-to-end test matrix

### Do

For each station type in use, run an inbound call to each entry point's number[^27]. Run a menu that needs DTMF, which Webex Contact Center requires as RFC 2833 on PSTN legs[^26]. Run a consult and a transfer to a dial number from Agent Desktop[^4]. Run an agent outdial and check the presented number against the Default Outdial ANI, the tenant's default dial number for outdial calls[^9].

### Verify

Calls reaching the Webex Contact Center media edge must use G.711uLaw or G.711aLaw[^96].

Suggested check: confirm every test completes with two-way audio for every station type in use.

## Applicability

Applies to: Cisco Webex Contact Center, Cisco Webex Calling Customer Assist, Cisco Webex Calling Dedicated Instance, Cisco Webex Calling, Cisco Unified CM, Cisco Unified Border Element, Cisco Unified Communications Manager, Cisco Webex Contact Center with Webex Calling, Cisco Webex Calling Cloud Connected PSTN, Cisco Webex Contact Center Agent Desktop, Cisco Webex Contact Center with Webex Dedicated Instance, Cisco Webex Calling Local Gateway, and Cisco Webex Contact Center Agent Desktop with Webex App. Deployments: on-premises, hybrid, multi-tenant, dedicated instance, and on-premises-gateway. Sources checked 2026-10-01. The Local Gateway steps apply to Cisco IOS XE 17.6.1a or later for registration-based deployments and 17.9.1a or later for certificate-based deployments[^35]. The Unified CM SIP trunk task flow cited here is the Unified CM 15 SIP trunk task flow[^51]. The Dedicated Instance branches follow Cisco's Dedicated Instance agent phone options[^16][^17]. The browser branch excludes tenants hosted in the Japan data center[^57]. Managing Webex Calling calls from Agent Desktop applies to Webex App 44.12 or later[^83]. Webex Calling Customer Assist for Unified CM is a separate product that carries calls between Webex Calling and Unified CM through a Local Gateway and requires Unified CM version 14 and SUs, version 15 and SUs, or later[^7][^8]. Unified CM 15SU4 adds Webex Calling Hybrid for Customer Assist[^97].

## What remains uncertain

The caller number that the agent's Unified CM phone displays on the agent leg is not covered by the sources below. The Unified CM digit manipulation needed to match +E.164 called numbers on the agent leg against agent directory numbers is not covered by the sources below. Whether Unified CM consult and transfer destinations need their own dial plan patterns is not covered by the sources below. What happens when an agent uses the phone's own transfer control instead of Agent Desktop is not covered by the sources below. Whether Extension sign-in can deliver calls to a Unified CM directory number is not covered by the sources below. The dial plan routing choice for agent legs in the Dedicated Instance branches is not covered by the sources below. RONA, recording and supervisor monitoring behaviour for agents signed in with Dial Number on a Unified CM phone is not covered by the sources below.

## Sources

[^1]: Desktop profile Agent DN validation can be Unrestricted, allowing any DN at sign-in, or Provisioned DN, restricting sign-in to a pre-configured default DN. Source: [Desktop profiles (Webex Contact Center)](https://help.webex.com/en-us/article/nvaf71f/), Voice Channel Options > Agent DN Validation. Checked 2026-10-01.
[^2]: Agents signed in with Dial Number or Extension answer incoming contact center calls on their physical phone and use its mute and keypad. Source: [Manage your calls in Agent Desktop](https://help.webex.com/en-us/article/mmcf7p), Answer a voice call. Checked 2026-10-01.
[^3]: A dial number entered for consult or transfer in Agent Desktop can contain 3 to 18 digits plus the special characters +, #, * and :. Source: [Manage your calls in Agent Desktop](https://help.webex.com/en-us/article/mmcf7p), Consult a call / Transfer a call > Dial Number. Checked 2026-10-01.
[^4]: From Agent Desktop, a voice call can be consulted or transferred to an agent, a queue, a dial number, an entry point or an organization expert. Source: [Manage your calls in Agent Desktop](https://help.webex.com/en-us/article/mmcf7p), Consult and transfer sections. Checked 2026-10-01.
[^5]: The desktop profile Consult to Queue toggle lets agents choose queues as consult targets, and choosing an entry point as the target disables the Consult button. Source: [Desktop profiles (Webex Contact Center)](https://help.webex.com/en-us/article/nvaf71f/), Voice Channel Options > Consult to Queue. Checked 2026-10-01.
[^6]: A consult or transfer from Agent Desktop to a Unified CM number most likely leaves through the same Control Hub dial plan and Local Gateway trunk as the agent leg, so the dial plan patterns must also cover Unified CM consult destinations (inferred). Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Outbound Premise-based Local Gateway Dial Plan, read with mmcf7p consult to Dial Number. Checked 2026-10-01.
[^7]: Webex Calling Customer Assist for Unified CM carries calls between Webex Calling and Unified CM through a Local Gateway, with a trunk and route group on each side. Source: [Configure Webex Calling Customer Assist for Unified Communications Manager](https://help.webex.com/en-us/article/n8md850/Configure-Webex-Calling-Customer-Assist-for-Unified-Communications-Manager), Configuration overview (trunk and route group). Checked 2026-10-01.
[^8]: Webex Calling Customer Assist with Unified CM requires Unified CM clusters on version 14 and SUs, version 15 and SUs, or later. Source: [Configure Webex Calling Customer Assist for Unified Communications Manager](https://help.webex.com/en-us/article/n8md850/Configure-Webex-Calling-Customer-Assist-for-Unified-Communications-Manager), Prerequisites. Checked 2026-10-01.
[^9]: The Webex Contact Center Default Outdial ANI is the tenant's default dial number for outdial calls, and a number must be mapped to an entry point to be eligible. Source: [Set up voice settings for Webex Contact Center](https://help.webex.com/en-us/article/gsmsaeb/Set-up-voice-settings-for-Webex-Contact-Center), Default Outdial ANI. Checked 2026-10-01.
[^10]: Webex Contact Center supports SIP Delayed Offer and does not support SIP Early Offer. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), PSTN Media and Signaling Requirements for Webex Contact Center. Checked 2026-10-01.
[^11]: Selecting Desktop as the agent destination lets agents use WebRTC-based calling directly from their browser. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Agent Destination Selection in Webex Contact Center > Desktop. Checked 2026-10-01.
[^12]: With Cloud Connected PSTN, the inbound call is routed to Webex Contact Center and then back to the Dedicated Instance agent's phone. Source: [Webex Dedicated Instance Contact Center integration](https://help.webex.com/en-us/article/nmhk7ve/Webex-Dedicated-Instance-Contact-Center-Integration), Option 2 > Cloud Connected PSTN. Checked 2026-10-01.
[^13]: For Dedicated Instance agent phones, Cisco directs creating a codec list with G.711 u-law first, then G.711 A-law, then Opus. Source: [Webex Dedicated Instance Contact Center integration](https://help.webex.com/en-us/article/nmhk7ve/Webex-Dedicated-Instance-Contact-Center-Integration), Audio configuration / codec preferences. Checked 2026-10-01.
[^14]: When Dedicated Instance agents use a Dedicated Instance Local Gateway, the inbound contact center number should be routed to multi-tenant over the inter-op SIP trunk. Source: [Webex Dedicated Instance Contact Center integration](https://help.webex.com/en-us/article/nmhk7ve/Webex-Dedicated-Instance-Contact-Center-Integration), Option 2 > Local Gateway. Checked 2026-10-01.
[^15]: For the Dedicated Instance contact center integration, certificate-based (mTLS) trunks must be used because registration-based trunks are no longer supported. Source: [Webex Dedicated Instance Contact Center integration](https://help.webex.com/en-us/article/nmhk7ve/Webex-Dedicated-Instance-Contact-Center-Integration), SIP trunk requirements. Checked 2026-10-01.
[^16]: With Dedicated Instance, the other option configures agent phones directly in Dedicated Instance, with PSTN through a Dedicated Instance Local Gateway or Cloud Connected PSTN in multi-tenant. Source: [Webex Dedicated Instance Contact Center integration](https://help.webex.com/en-us/article/nmhk7ve/Webex-Dedicated-Instance-Contact-Center-Integration), Agent phone deployment options, Option 2. Checked 2026-10-01.
[^17]: With Dedicated Instance, one option places agent phones on Webex Calling multi-tenant and back-office users in Dedicated Instance, connected by the default inter-op SIP trunk between the calling platforms. Source: [Webex Dedicated Instance Contact Center integration](https://help.webex.com/en-us/article/nmhk7ve/Webex-Dedicated-Instance-Contact-Center-Integration), Agent phone deployment options, Option 1. Checked 2026-10-01.
[^18]: The Dial Number agent destination is a free-form numeric entry that can be an enterprise DID or a public PSTN number, and it must be reachable through Webex PSTN and routing. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), +E.164 Globalized Call Routing Support for Multinational Contact Center Deployments > Agent Destination Selection in Webex Contact Center. Checked 2026-10-01.
[^19]: One Webex Calling dial plan can hold up to 10,000 dial patterns. Source: [Configure trunks, route groups, and dial plans for Webex Calling](https://help.webex.com/en-us/article/n0xb944/Configure-trunks,-route-groups,-and-dial-plans-for-Webex-Calling), Configurable limits table. Checked 2026-10-01.
[^20]: For Local Gateway deployments, the dial plan that routes calls toward the on-premises PBX must contain a pattern that matches the agent's destination. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Webex Calling PSTN and Premise based Agents Configuration. Checked 2026-10-01.
[^21]: In a Webex Calling dial pattern, ! may occur only once, only at the end and only in an E.164 pattern, X cannot sit in the middle of a number, and X and ! cannot be combined. Source: [Configure trunks, route groups, and dial plans for Webex Calling](https://help.webex.com/en-us/article/n0xb944/Configure-trunks,-route-groups,-and-dial-plans-for-Webex-Calling), Dial patterns > wildcard restrictions. Checked 2026-10-01.
[^22]: Webex Calling dial plans are configured globally for the enterprise and apply to all users regardless of location. Source: [Configure trunks, route groups, and dial plans for Webex Calling](https://help.webex.com/en-us/article/n0xb944/Configure-trunks,-route-groups,-and-dial-plans-for-Webex-Calling), Dial plans overview. Checked 2026-10-01.
[^23]: Premise-based dial plan patterns for Webex Contact Center can include +E.164 prefixes, SIP URIs or location-specific prefixes. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Outbound Premise-based Local Gateway Dial Plan. Checked 2026-10-01.
[^24]: When creating a Webex Calling dial plan, the administrator selects a previously created trunk or route group as its routing choice. Source: [Configure trunks, route groups, and dial plans for Webex Calling](https://help.webex.com/en-us/article/n0xb944/Configure-trunks,-route-groups,-and-dial-plans-for-Webex-Calling), Create a dial plan. Checked 2026-10-01.
[^25]: Webex Calling dial plan E.164 patterns start with + and enterprise patterns are digits only; X matches one digit and ! matches any digit sequence. Source: [Configure trunks, route groups, and dial plans for Webex Calling](https://help.webex.com/en-us/article/n0xb944/Configure-trunks,-route-groups,-and-dial-plans-for-Webex-Calling), Dial patterns. Checked 2026-10-01.
[^26]: Webex Contact Center requires DTMF to be carried as RFC 2833 on PSTN legs. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), PSTN Media and Signaling Requirements for Webex Contact Center. Checked 2026-10-01.
[^27]: An inbound entry point is created under Services > Contact Center > Customer Experience > Channels by selecting a Webex Calling PSTN number and its Webex Calling location; the numbers can first be checked under Calling > Numbers. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Local Gateway configuration steps (verify numbers under Calling > Numbers; create entry point). Checked 2026-10-01.
[^28]: The Extension agent destination is a short-form internal number that may correspond to a Webex Calling or Unified Communications endpoint, and Webex Contact Center attempts to match it with a registered Webex Calling endpoint to enable phone control features. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Agent Destination Selection in Webex Contact Center > Extension. Checked 2026-10-01.
[^29]: Webex Contact Center accepts only G.711 u-law or A-law on PSTN legs and does not transcode, so any other codec such as G.729, iLBC or Opus must be transcoded before reaching it. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), PSTN Media and Signaling Requirements for Webex Contact Center. Checked 2026-10-01.
[^30]: The inbound calling search space of the Unified CM trunk facing the Local Gateway must include the partition of the agent directory numbers, or Webex Contact Center agent-leg calls cannot reach the agent phones (inferred). Source: [Cisco Unified Communications Manager SIP Integration Guide for Cisco Unity Connection Release 15 - Setting Up a Cisco Unified Communications Manager SIP Trunk Integration](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/connection/15/integration/cucm_sip/b_15cucintcucmsip/b_14cucintcucmsip_chapter_010.html), Create SIP trunk task, Step 6, read with registry claim cisco-unified-cm-css-definition. Checked 2026-10-01.
[^31]: The International Dialing Format option at Dial Number sign-in lets Webex Contact Center route a call destined for a PSTN or premise-based agent using +E.164 addressing. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Configuration of Agents Connectivity to PSTN services > Webex Calling PSTN and Premise based Agents Configuration. Checked 2026-10-01.
[^32]: In Cisco's example, dial-peer 300 reaches Unified CM through a DNS SRV session target that resolves to multiple Unified CM nodes. Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), dial-peer voice 300 configuration step. Checked 2026-10-01.
[^33]: In that design, the incoming dial-peer from Webex (100) applies dial-peer group 300, whose dial-peer 300 sends the call to the Unified CM Webex trunk, and the reverse direction uses dial-peer group 100. Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), Local Gateway with Unified CM > dial-peer groups. Checked 2026-10-01.
[^34]: Cisco's Local Gateway example configures voice class codec 100 to allow only G.711 codecs on all trunks. Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), voice class codec 100 step. Checked 2026-10-01.
[^35]: Registration-based Local Gateway deployments require Cisco IOS XE 17.6.1a or later, and certificate-based deployments require 17.9.1a or later. Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), Prerequisites / version requirements. Checked 2026-10-01.
[^36]: Local Gateway numbers for Webex Contact Center, both DID and toll-free, are provisioned in Control Hub in +E.164 format. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Webex Calling Local Gateway (LGWY). Checked 2026-10-01.
[^37]: To route calls from Webex Contact Center to on-premises destinations such as agents, an Outbound Dial Plan is created in Control Hub under Calling > Call Routing > Dial Plans with a Name, Routing Choice and Patterns. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Outbound Premise-based Local Gateway Dial Plan. Checked 2026-10-01.
[^38]: After the trunk is added, a Route Group is created under Calling > Call Routing > Route Group with the trunk assigned, and the location is set to Premise-Based PSTN under Locations > Calling. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Control Hub Local Gateway Activation. Checked 2026-10-01.
[^39]: A Local Gateway trunk is added in Control Hub under Calling > Call Routing > Trunk as Registration based or Certificate Based, and Certificate Based is required for deployments needing more than 250 concurrent calls. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Control Hub Local Gateway Activation. Checked 2026-10-01.
[^40]: In Cisco's Local Gateway with Unified CM design, calls from Unified CM to the gateway on port 5060 go to the PSTN and calls on port 5065 go to Webex Calling. Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), Local Gateway with Unified CM call flow section. Checked 2026-10-01.
[^41]: Webex Contact Center does not support SIP Early Media on PSTN legs. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), PSTN Media and Signaling Requirements for Webex Contact Center. Checked 2026-10-01.
[^42]: Webex Contact Center agents can use a telephony device connected to a PBX such as Cisco Unified Communications Manager. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Configuration of Agents Connectivity to PSTN services > Premise-Based Agents or PSTN. Checked 2026-10-01.
[^43]: The Agent Desktop incoming voice call popover shows between three and six variables chosen by the administrator in Flow Designer, excluding secure variables. Source: [Manage your calls in Agent Desktop](https://help.webex.com/en-us/article/mmcf7p), Answer a voice call > popover. Checked 2026-10-01.
[^44]: Agents whose phone sits on a premise-based PBX select Dial Number at sign-in and enter the destination the call should be routed to. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Webex Calling PSTN and Premise based Agents Configuration. Checked 2026-10-01.
[^45]: A Webex Contact Center desktop profile controls which voice options agents may sign in with: Agent DN, Extension or Desktop (browser). Source: [Desktop profiles (Webex Contact Center)](https://help.webex.com/en-us/article/nvaf71f/), Voice Channel Options. Checked 2026-10-01.
[^46]: At Agent Desktop sign-in, the agent picks Desktop, Extension or Dial Number from the Handle calls using list, which shows only the options the agent's profile allows, and a single configured value is pre-filled. Source: [Sign in to Agent Desktop](https://help.webex.com/en-us/article/n6lmci8), Sign in to Agent Desktop, step 5. Checked 2026-10-01.
[^47]: With the International dialing format checkbox the agent enters + country code and number; without it the agent uses E.164 format such as +11234567890 or IDD format. Source: [Sign in to Agent Desktop](https://help.webex.com/en-us/article/n6lmci8), Sign in to Agent Desktop, step 5 (Dial Number). Checked 2026-10-01.
[^48]: Cisco advises making successful inbound and outbound calls over the chosen Webex Calling PSTN connectivity option before completing the remaining Webex Contact Center voice tasks. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Webex Calling PSTN connectivity prerequisites (sentence beginning 'Before deploying Webex Contact Center'). Checked 2026-10-01.
[^49]: Because Webex delivers agent-leg called numbers in +E.164, Unified CM must either hold the agent directory numbers in +E.164 form or manipulate the inbound called number so that it matches the agent directory number (inferred). Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), number format discussion, read with cisco-help-2dputx intl dialing format section. Checked 2026-10-01.
[^50]: Because the Extension option is matched against registered Webex Calling endpoints and premise PBX agents are told to use Dial Number, a Unified CM phone is most safely reached by signing in with Dial Number rather than Extension (inferred). Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Agent Destination Selection in Webex Contact Center; Webex Calling PSTN and Premise based Agents Configuration. Checked 2026-10-01.
[^51]: The Unified CM 15 SIP trunk task flow is to configure a SIP profile, then a SIP trunk security profile, then the SIP trunk that applies both. Source: [System Configuration Guide for Cisco Unified Communications Manager Release 15 and SUs - Configure Trunks](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/15/systemConfig/cucm_b_system-configuration-guide-15/cucm_b_system-configuration-guide-14_chapter_01000.html), SIP Trunk Configuration Task Flow. Checked 2026-10-01.
[^52]: On a Unified CM SIP trunk, the Inbound Calls Calling Search Space is set to a calling search space that contains the phones the trunk's inbound calls must reach. Source: [Cisco Unified Communications Manager SIP Integration Guide for Cisco Unity Connection Release 15 - Setting Up a Cisco Unified Communications Manager SIP Trunk Integration](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/connection/15/integration/cucm_sip/b_15cucintcucmsip/b_14cucintcucmsip_chapter_010.html), Create SIP trunk task, Step 6 (Inbound Calls). Checked 2026-10-01.
[^53]: When creating the Webex Calling trunk in Unified CM, the incoming port in its SIP Trunk Security Profile is set to 5065 so Unified CM accepts messages on that port and puts it in the Via header toward the Local Gateway. Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), Local Gateway with Unified CM (note on SIP Trunk Security Profile). Checked 2026-10-01.
[^54]: Cisco instructs agents to start hold, resume, consult and transfer from Agent Desktop rather than from a hardphone or softphone. Source: [Manage your calls in Agent Desktop](https://help.webex.com/en-us/article/mmcf7p), Hold, consult and transfer sections (notes). Checked 2026-10-01.
[^55]: The Local Gateway guide states that Webex presents numbers to the gateway in +E.164 format. Source: [Configure Local Gateway on Cisco IOS XE for Webex Calling](https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling), number format discussion in the Local Gateway configuration sections. Checked 2026-10-01.
[^56]: The supported browsers for Webex Contact Center WebRTC calling are Google Chrome, Microsoft Edge and Mozilla Firefox. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), WebRTC Configuration. Checked 2026-10-01.
[^57]: The Desktop (WebRTC) option is currently unavailable for Webex Contact Center customers hosted in the Japan data center. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), WebRTC Configuration; Agent Destination Selection in Webex Contact Center > Desktop. Checked 2026-10-01.
[^58]: The Webex Contact Center WebRTC (Desktop) option needs a minimum network bandwidth of 100 kbps per call. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), WebRTC Configuration. Checked 2026-10-01.
[^59]: Agent Desktop does not currently support headset control actions for WebRTC (Desktop) calls. Source: [Sign in to Agent Desktop](https://help.webex.com/en-us/article/n6lmci8), Sign in to Agent Desktop, step 5 (Desktop). Checked 2026-10-01.
[^60]: Virtual Desktop Infrastructure (VDI) does not support the Webex Contact Center WebRTC desktop option. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), WebRTC Configuration. Checked 2026-10-01.
[^61]: A valid Webex Calling subscription is required for Webex Contact Center agents that use Webex devices or the Webex App. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Webex Calling Device Agent Configuration. Checked 2026-10-01.
[^62]: Webex Calling agents can sign in with an +E.164 Dial Number, but then phone control features such as preferred device and answering from Agent Desktop are not available. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Webex Calling Device Agent Configuration. Checked 2026-10-01.
[^63]: For Extension sign-in, Webex Calling devices must be provisioned with an extension and associated to the Calling users acting as Contact Center agents, and agents choose Extension, enter that extension and click Submit. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/2dputx/Set-up-voice-channels-for-Webex-Contact-Center), Webex Calling Device Agent Configuration. Checked 2026-10-01.
[^64]: Webex Calling components including PSTN connectivity and agent endpoints should be configured and validated prior to the configuration of the Webex Contact Center tenant, because pre-configuring them significantly accelerates the deployment and simplifies the process. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb), Webex Calling Provisioning and Configuration for Webex Contact Center. Checked 2026-09-16.
[^65]: Because the tenant's telephony selection is locked after activation and the administrator cannot correct it, checking Service Details before any other configuration avoids building locations and entry points on a tenant that Cisco must first reprovision (inferred). Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb/webexcc_t_change-the-telephony-option-for-a-webex-contact-center-tenant.html), section Verification of Webex Contact Center Service Details. Checked 2026-09-24.
[^66]: The PSTN Services section of the voice channel article lists four PSTN options for Webex Contact Center: Webex Contact Center PSTN, Webex Cloud Connected PSTN, Cisco Calling Plan and Webex Calling Local Gateway. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb/webexcc_t_change-the-telephony-option-for-a-webex-contact-center-tenant.html), section PSTN Services. Checked 2026-09-24.
[^67]: A Webex Calling Local Gateway lets a customer retain their current on-premises PSTN carrier while providing access in over 140 markets globally, with third-party session border controllers supported alongside Cisco CUBE. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb), Connect to Webex Calling Services - PSTN Services - Webex Calling Local Gateway. Checked 2026-09-16.
[^68]: Webex Calling Cloud Connected PSTN provides connectivity in over 65 countries through Certified Calling Providers, and numbers provisioned through it are stored in plus-E.164 format. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb), Connect to Webex Calling Services - PSTN Services - Webex Calling Cloud Connected PSTN. Checked 2026-09-16.
[^69]: Webex Calling Customer Assist is an elevated Webex Calling Call Queue rather than a separate contact centre: an existing Call Queue is upgraded to Customer Assist while maintaining the existing settings, and agents and supervisors work from the Webex App. Source: [Webex Calling Customer Assist](https://help.webex.com/en-us/article/72sb3r), article introduction. Checked 2026-09-16.
[^70]: A registration-based Webex Calling Local Gateway processes up to 250 concurrent calls into Webex Contact Center, and deployments needing more than 250 concurrent calls including IVR and agent legs must select a certificate-based trunk. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb), Configuration of Webex Local Gateway / Session Border Controller Configuration for Local Gateway Connectivity. Checked 2026-09-16.
[^71]: A Webex Calling location's PSTN connection is set on the location's Calling tab by choosing Cisco PSTN, Cloud Connected PSTN, or Premises-based PSTN through a Local Gateway. Source: [Configure Webex Calling for your organization](https://help.webex.com/en-us/article/njvdjf2/Configure-Webex-Calling-for-your-organization), section on PSTN connection for a location. Checked 2026-09-24.
[^72]: SIP Delayed Offer is supported toward Webex Contact Center while SIP Early Offer and SIP Early Media are not supported and are described as roadmap items. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb), PSTN Media and Signaling Requirements for Webex Contact Center. Checked 2026-09-16.
[^73]: An inbound voice entry point is created with channel type Inbound Telephony and a routing flow selected from a drop-down, and its timezone defaults to the tenant timezone. Source: [Set up a channel](https://help.webex.com/en-us/article/ewuay1/Set-up-a-channel), procedure Create a channel, Channel Type, Timezone and Routing Flow fields. Checked 2026-09-24.
[^74]: A Webex Calling location's main number does not appear in the list of numbers available for entry point mapping, so using it for mapping requires changing the location's main number. Source: [Set up voice settings for Webex Contact Center](https://help.webex.com/en-us/article/gsmsaeb/Set-up-voice-settings-for-Webex-Contact-Center), section on numbers available from Webex Calling locations. Checked 2026-09-24.
[^75]: Webex Contact Center system limits allow 6000 active entry points, 1000 active outdial entry points, 15000 dialed numbers configured as entry points in total and 500 dialed numbers per entry point. Source: [System limits in Webex Contact Center](https://help.webex.com/en-us/article/n7s6ed7), Table 1. Maximum system limits for configuration entities and attributes - entry point and dialed number rows. Checked 2026-09-16.
[^76]: Dedicated Instance integrations with Webex Contact Center require a codec list ordered G.711 U-Law first, then G.711 A-Law, then OPUS, built from Factory Default Lossy and assigned across CTI, endpoints and SIP trunk device pool regions, and this must be done only for the Webex Contact Center integrations. Source: [Webex Dedicated Instance Contact Center integration](https://help.webex.com/en-us/article/nmhk7ve), Deployment considerations and constraints. Checked 2026-09-16.
[^77]: Webex Contact Center supports five agent calling devices: a Webex Calling desk phone, the Webex Calling desktop app, the Webex App for mobile, the Webex App integrated with Webex Calling, and the Microsoft Teams softphone. Source: [System requirements for Webex Contact Center Desktop](https://help.webex.com/en-us/article/besrkt/System-requirements-for-Webex-Contact-Center-Desktop), section Agent devices. Checked 2026-09-24.
[^78]: The minimum supported Agent Desktop browsers are Chrome 144+, Microsoft Edge 144+ and Firefox 140+. Cisco recommends the latest stable versions. Source: [System requirements for Webex Contact Center Desktop](https://help.webex.com/en-us/article/besrkt/System-requirements-for-Webex-Contact-Center), Supported browsers table, Minimum column. Checked 2026-09-30.
[^79]: Agent Desktop is supported on VDI, but WebRTC (browser-based agent audio) is not supported on VDI. Source: [System requirements for Webex Contact Center Desktop](https://help.webex.com/en-us/article/besrkt/System-requirements-for-Webex-Contact-Center), VDI note in system requirements. Checked 2026-09-30.
[^80]: A Unified CM partition is a logical group of route patterns, directory numbers, translation patterns, transformation patterns, URIs and hunt pilots that divides the route plan into logical subsets. Source: [System Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Configure Partitions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/15/systemConfig/cucm_b_system-configuration-guide-15/cucm_b_system-configuration-guide-14_chapter_010000.html), Configure Partitions, Partitions Overview. Checked 2026-09-30.
[^81]: A calling search space is a prioritized list of partitions. A caller can reach a destination only if the destination's partition is in the caller's calling search space. Source: [System Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Configure Partitions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/15/systemConfig/cucm_b_system-configuration-guide-15/cucm_b_system-configuration-guide-14_chapter_010000.html), Configure Partitions, Calling Search Spaces overview. Checked 2026-09-30.
[^82]: In the Webex Contact Center architecture, an agent's destination number can be a PSTN phone, a mobile phone, or an extension if the agent is a Cisco Webex Calling user. Source: [Webex Contact Center Architecture](https://help.webex.com/en-us/article/utqcm7), Functional Components - Routing and Queueing - Voice/Telephony-specific capabilities. Checked 2026-09-16.
[^83]: Managing Webex Calling calls from Agent Desktop requires Webex App 44.12 or later, requires Webex Calling to be turned on in Control Hub, and applies when the agent signs in with Dial Number or Extension. Source: [Optimize Webex Contact Center Desktop call notifications](https://help.webex.com/en-us/article/u5dbtfb), Using Webex App for calls. Checked 2026-09-16.
[^84]: The Manage Webex Calling calls in Agent Desktop option is meant only for the Agent persona and does not work correctly for supervisors during monitoring, barge-in or similar call scenarios, where the answer button is not available. Source: [Optimize Webex Contact Center Desktop call notifications](https://help.webex.com/en-us/article/u5dbtfb), Using Webex App for calls. Checked 2026-09-16.
[^85]: As of March 13 2026, agent status is automatically aligned between Webex Calling and Webex Contact Center as part of the CTI connector enhancements. Source: [What's new for administrators in Webex Contact Center](https://help.webex.com/en-us/article/a1gx3h), March 13, 2026 - CTI connector enhancements. Checked 2026-09-16.
[^86]: The Country of Operation chosen in the setup wizard's Contact Center tab decides which data center hosts the tenant: the system creates it in the data center closest to that country. Source: [Data Locality in Webex Contact Center](https://help.webex.com/en-us/article/n0p6xa1/Data-Locality-in-Webex-Contact-Center), sentence beginning 'When you pick a Country of Operation in the set up wizard'. Checked 2026-09-30.
[^87]: Agent Desktop needs at least 4 GB of RAM. 8 GB or more is recommended. Source: [System requirements for Webex Contact Center Desktop](https://help.webex.com/en-us/article/besrkt/System-requirements-for-Webex-Contact-Center), requirements table, Memory row. Checked 2026-09-30.
[^88]: Agent DN validation in a desktop profile is either Unrestricted, which lets agents sign in with any DN, or Provisioned DN, which restricts sign-in to the default DN set in the agent's user settings. Source: [Create and manage desktop profiles](https://help.webex.com/en-us/article/nvaf71f/Create-and-manage-desktop-profiles), Agent DN Validation field. Checked 2026-09-24.
[^89]: When an administrator configures a Default DN, it is prepopulated in the Dial Number and Extension fields and shown as a placeholder; where the DN is restricted to that default the fields become read-only and the agent skips those steps, and a saved sign-in preference takes precedence over the configured Default DN. Source: [Sign in to Agent Desktop](https://help.webex.com/en-us/article/n6lmci8), Default DN behaviour in sign-in. Checked 2026-09-16.
[^90]: A desktop profile's voice channel options control which sign-in methods agents may use: Agent DN, Extension and Desktop, where Desktop means signing in through a browser using WebRTC. Source: [Create and manage desktop profiles](https://help.webex.com/en-us/article/nvaf71f/Create-and-manage-desktop-profiles), Voice Channel Options fields. Checked 2026-09-24.
[^91]: The Desktop option enables agents to take calls using WebRTC-based calling directly from the browser and requires no further input at sign-in. Source: [Sign in to Agent Desktop](https://help.webex.com/en-us/article/n6lmci8), Handle calls using - Desktop. Checked 2026-09-16.
[^92]: The tenant-wide default outdial ANI is set in Control Hub under Tenant Settings, Voice, and a dial number must be mapped to an entry point before it can be chosen as the default outdial ANI. Source: [Set up voice settings for Webex Contact Center](https://help.webex.com/en-us/article/gsmsaeb/Set-up-voice-settings-for-Webex-Contact-Center), section Default Outdial ANI. Checked 2026-09-24.
[^93]: By default the first dial number mapped to an entry point is shown as the default outdial ANI, and if no dial number is mapped to an entry point the field reads Not Configured. Source: [Set up voice settings for Webex Contact Center](https://help.webex.com/en-us/article/gsmsaeb/Set-up-voice-settings-for-Webex-Contact-Center), section Default Outdial ANI. Checked 2026-09-24.
[^94]: An agent uses the system-wide default outbound ANI unless a specific default ANI is configured in an Outdial ANI list linked to the agent's desktop profile, which overrides it. Source: [Set up voice settings for Webex Contact Center](https://help.webex.com/en-us/article/gsmsaeb/Set-up-voice-settings-for-Webex-Contact-Center), section Default Outdial ANI. Checked 2026-09-24.
[^95]: A desktop profile holds three outdial settings: an Outdial toggle that lets agents make outdial calls, an Outdial Entry Point the agent uses for those calls, and an Outdial ANI list naming the numbers the agent may present. Source: [Create and manage desktop profiles](https://help.webex.com/en-us/article/nvaf71f/Create-and-manage-desktop-profiles), Voice Channel Options, Outdial, Outdial Entry Point and Outdial ANI fields. Checked 2026-09-24.
[^96]: Calls reaching the Webex Contact Center media edge must use G.711uLaw or G.711aLaw. Source: [Set up voice channels for Webex Contact Center](https://help.webex.com/en-us/article/nhy3codb), PSTN Media and Signaling Requirements for Webex Contact Center. Checked 2026-09-16.
[^97]: 15SU4 adds Webex Calling Hybrid for Customer Assist, a hybrid model that combines cloud-based agent functions with on-premises Unified CM telephony. Source: [Release Notes for Cisco Unified Communications Manager Release 15SU4a and the IM and Presence Service Release 15SU4](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/rel_notes/15/SU4/cucm_b_release-notes-for-cucm-imp-15su4.html), New and Changed Features, Webex Calling Hybrid for Customer Assist. Checked 2026-09-30.