Unity Connection networking
Verified 2026-09-25 · 60 sources · tier 2
Also known as HTTPS networking, VPIM networking, intersite networking, intrasite networking, legacy networking.
Cisco Unity Connection networking connects multiple Unity Connection locations to share directory data and exchange voice messages 1430. Architectures include HTTPS networking, legacy intrasite and intersite networking, and VPIM version 2 connections to third-party messaging systems 3852.
HTTPS networking
An HTTPS network connects at most 25 Unity Connection locations in a hub-and-spoke topology 119. Hub locations maintain several HTTPS links, spoke locations have exactly 1 link, and directory data between spokes passes through the hubs 9. No location may have more than 5 direct HTTPS links, and the network may be at most 2 levels deep 128. HTTPS networking supports only a single-site network, meaning multiple HTTPS networks cannot be connected to one another 15.
Only Unity Connection 10.x and later servers can join an HTTPS network 13. A server cannot join if its display name or SMTP domain matches that of another server already in the network 45. For a Unity Connection cluster, only the publisher server is joined to the network 1. When a cluster is networked, the other locations must reach it through a smart host that resolves the cluster's SMTP domain to both the publisher and subscriber IP addresses 2. Round-trip latency between hub and spoke nodes in an HTTPS network should not exceed 250 ms 10.
Directory data is exchanged over HTTP on TCP port 8081 or HTTPS on TCP port 8444, while voice messages are exchanged over SMTP on TCP port 25 directly or through a smart host 14. Directory replication uses a Feeder service and a Reader service, where the Reader polls the remote Feeder for changes since the last poll and the Feeder answers from its change-tracking data 5. By default, the directory-data and recorded-name synchronisation tasks are enabled and run every 15 minutes 16. Initial directory replication between newly linked locations can take from a few minutes to a few hours, depending on directory size 18.
By default, HTTPS networking does not replicate system distribution lists and their membership; enabling the HTTPS link setting 'Include distribution lists and membership when synchronizing directory data' turns it on 4. Objects can belong only to local partitions, though remote partitions can still be added to local search spaces 32. System call handler owners must be local users 32.
Cisco's setup task list for an HTTPS network specifies linking servers, then configuring smart hosts and SMTP access for cluster subscribers, then verifying replication, and subsequently configuring search spaces, security, cross-server features, and testing 17. The hostname or IP address of an HTTPS-networked location cannot be changed while linked; the location must be removed from the network, modified, and then relinked 6. After a location is removed, the 'Remove Objects Associated With Deleted Network Location' task purges its objects, running by default daily at 10:00 p.m., a schedule Cisco recommends keeping 39.
Directory capacity limits
The Release 14 HTTPS Networking Guide lists 160,000 users as the directory limit and notes that 14SU2 and earlier support 100,000 users 47. The HTTPS network directory limits include 150,000 contacts, 100,000 system distribution lists, 25,000 users per list, 1.5 million total list members, and 20 levels of list nesting 7. In legacy intrasite and intersite networking, the global directory limit is 100,000 users and system contacts combined, with the same distribution list limits as HTTPS networking 31.
| Metric | Legacy (intrasite/intersite) limit | HTTPS network limit |
|---|---|---|
| Total locations | 10 per site, 20 across 2 sites 2920 | 25 11 |
| User directory capacity | 100,000 combined users and contacts 31 | 160,000 users (Release 14; 100,000 in 14SU2 and earlier) 47 |
| System contacts | Combined in 100,000 user limit 31 | 150,000 7 |
| System distribution lists | 100,000 31 | 100,000 7 |
| Members per list | 25,000 31 | 25,000 7 |
| Total list members | 1.5 million 31 | 1.5 million 7 |
| List nesting depth | 20 levels 31 | 20 levels 7 |
Legacy networking (intrasite and intersite)
A legacy Unity Connection site (intrasite networking) supports at most 10 Unity Connection servers or clusters 29. Within an intrasite network, every location uses SMTP to exchange both directory synchronisation information and voice messages directly with every other location 30. Legacy networking tracks directory changes using Unique Sequence Numbers (USNs), where each change increments the location's USN by 1 and is recorded in its database 50.
An intersite link connects exactly 2 Unity Connection sites, raising the total supported locations from 10 to 20; no more than 2 sites can be linked 20. A site can possess only 1 intersite link, preventing simultaneous links to another Unity Connection site and a Cisco Unity site 23. Intersite networking is not supported with Cisco Business Edition 21.
For an intersite link, 1 location in each site acts as the site gateway, carrying all intersite directory synchronisation and voice messaging traffic 19. Intersite gateways exchange directory updates over HTTP on port 80 or HTTPS on port 443, and exchange messages over SMTP on port 25 directly or via a smart host 25. By default, the intersite Reader polls the remote Feeder every 15 minutes, using separate tasks for directory data and recorded names 24.
System contacts, system distribution list membership, and VPIM locations and contacts are not replicated across an intersite link 22. Message recall does not work across sites linked by an intersite link 33. Additionally, dispatch messages and broadcast messages cannot be sent across networked locations, whether intrasite or intersite 3.
Legacy (SMTP) networking and HTTPS networking cannot run simultaneously in the same network 38. SAML SSO cannot be used to access all nodes of an HTTPS, intrasite, or intersite network 40.
VPIM networking
Unity Connection VPIM networking uses VPIM version 2 (RFC 3801) over SMTP and MIME to interoperate with third-party voice messaging systems supporting VPIM version 2 52. Cisco recommends choosing 1 location in a site as the bridgehead that holds the configuration for VPIM locations and contacts 51.
Migration to HTTPS networking
Migrating from legacy networking to HTTPS networking is supported only via a manual procedure; there is no automated migration tool 35. Prior to migration, all locations must be upgraded to Release 15, replication must be healthy and in sync with none stalled, and every location must be backed up 36.
The migration process requires a downtime window whose length depends on the number of locations and directory size 34. The flash-cut sequence backs up distribution lists using the Distribution List Syncher, unjoins every location from the legacy network, takes a DRS backup, joins the locations in the HTTPS topology, enables distribution-list sync, and then restores the lists 37.
Cross-server features
Cross-server sign-in requires 'Respond to Cross-Server Handoff Requests' enabled on the receiving location, alongside 'Allow Cross-Server Sign-In to this Remote Location' and a cross-server dial string configured on the originating location 54. Handoffs are signalled in-band: the originating location holds the caller, dials the receiving location using the dial string, and both locations exchange DTMF tone sequences before call handoff completes 53. Only 1 cross-server dial string can be entered per receiving location; thus, an originating location with several phone system integrations requires a dial string usable by all of them 56.
Enabling cross-server transfer automatically enables cross-server live reply for users permitted live reply by their class of service 59. If identified subscriber messaging is disabled, cross-server live reply functions only for messages sent after users sign in to their mailboxes 55. When 2 locations are joined by an HTTPS link, video calls using cross-server features are downgraded to audio 60. Cisco recommends configuring identical search scopes on originating and receiving locations to prevent situations where a match on 1 location's scope fails to resolve on the other 58.
Troubleshooting
When creating an SSL-enabled HTTPS link, Unity Connection verifies that the entered IP address, FQDN, or hostname matches the remote location's web SSL certificate; if mismatched, administrators must supply the matching value or select 'Ignore Certificate Errors' 42.
Replication status can be checked on the Edit Unity Connection Location page by comparing the Last USN Sent, Received, and Acknowledged fields 44. If these fields stop incrementing, replication may be stalled, and the system re-requests records following a default 5-minute timeout 44. If RTMT raises a NetworkLoopDetected alert, Cisco instructs administrators to locate the loop using the Network Analyzer tool, unjoin the affected locations, and rejoin them in the correct hierarchy 41. A shortage of voice messaging ports can prevent cross-server transfers; Cisco suggests inspecting port utilization using the Unity Connection Port Usage Analyzer 57.
Applicability
Applies to: Cisco Unity Connection. Deployments: on-premises. Sources checked 2026-09-25. Prior to migration from legacy networking to HTTPS networking, all locations must be upgraded to Release 15 36. Intersite networking is not supported with Cisco Business Edition 21.
What remains uncertain
- Networked Unity Connection to Webex Calling voicemail migration (handling cross-server features and distribution lists) is not covered by the sources below.
- The authoritative HTTPS network directory user limit for Release 15 (100000 vs 160000) is not covered by the sources below.
- Unity Connection networking changes in any release after 15 (limits or deprecation of legacy networking) is not covered by the sources below.
- Release 15 SU release notes for networking fixes and changes is not covered by the sources below.
- Bandwidth sizing for HTTPS or intersite directory replication and SMTP message traffic is not covered by the sources below.
- Security Guide for Unity Connection 15 sections on SSL for networking links and certificate handling is not covered by the sources below.
- Community field patterns for stalled replication and link creation failures is not covered by the sources below.
- The meaning of the design guide sentence restricting intrasite networking to Business Edition is not covered by the sources below.
See also
Related to
- Moving from Unity Connection to Webex Calling voicemail — Networked Unity Connection estates (distribution lists; cross-server features; directory replication) must be accounted for when moving voicemail to Webex; this packet does not cover the migration.
- SRST on Cisco IOS XE — The Release 15 design guide networking chapter covers Survivable Remote Site Voicemail alongside SRST; its interaction with HTTPS networking is not documented in the sources read.
Referenced by
- Moving from Unity Connection to Webex Calling voicemail — Unity Connection side of the estate; relevant when Unity Connection stays for unmigrated users or moves into Dedicated Instance
Sources
- 1For a Unity Connection cluster, only the publisher server is joined to the network.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > cluster considerations · Checked 2026-09-25
- 2When a cluster is networked, the other locations must reach it through a smart host that resolves the cluster's SMTP domain to both the publisher and the subscriber IP addresses.Networking Guide for Cisco Unity Connection Release 15 - Setting Up Networking Between Cisco Unity Connection Servers · Setting Up Networking Between Cisco Unity Connection Servers > smart host configuration · Checked 2026-09-25
- 3Dispatch messages and broadcast messages cannot be sent across networked locations, whether within a site or between sites.Networking Guide for Cisco Unity Connection Release 15 - Setting Up Networking Between Cisco Unity Connection Servers · Setting Up Networking Between Cisco Unity Connection Servers > notes on broadcast and dispatch messages · Checked 2026-09-25
- 4By default, HTTPS networking does not replicate system distribution lists and their membership; the HTTPS link setting 'Include distribution lists and membership when synchronizing directory data' turns it on.Troubleshooting Guide for Cisco Unity Connection Release 15 - Troubleshooting Networking · Troubleshooting Networking > distribution lists in HTTPS networks · Checked 2026-09-25
- 5Intersite and HTTPS directory replication use a Feeder service and a Reader service: the Reader polls the remote Feeder for changes since the last poll, and the Feeder answers from its change-tracking data.Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > intersite networking (replication) · Checked 2026-09-25
- 6The hostname or IP address of an HTTPS-networked location cannot be changed while it is linked: remove it from the network, make the change, then relink it.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Making Changes to HTTPS Networking Configuration · Making Changes to HTTPS Networking Configuration > changing hostname or IP address · Checked 2026-09-25
- 7The HTTPS network directory limits include 150,000 contacts, 100,000 system distribution lists, 25,000 users per list, 1.5 million total list members and 20 levels of list nesting.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Overview of HTTPS Networking · Overview of HTTPS Networking > Directory Size Limits · Checked 2026-09-25
- 8An HTTPS network may be at most two levels deep.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > topology determination (hub/spoke rules) · Checked 2026-09-25
- 9HTTPS networking uses a hub-and-spoke topology: hub locations have several HTTPS links, spoke locations have exactly one, and directory data between spokes passes through the hubs.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Overview of HTTPS Networking · Overview of HTTPS Networking > hub and spoke topology · Checked 2026-09-25
- 10Round-trip latency between hub and spoke nodes in an HTTPS network should not exceed 250 ms.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Designing a Unity Connection Network using HTTPS · Checked 2026-09-25
- 11An HTTPS network of Cisco Unity Connection can connect at most 25 Unity Connection locations.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Overview of HTTPS Networking · Overview of HTTPS Networking > limits discussion · Checked 2026-09-25
- 12In an HTTPS network no location may have more than five direct HTTPS links.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > topology determination (hub/spoke rules) · Checked 2026-09-25
- 13Only Unity Connection 10.x and later servers can join an HTTPS network.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > prerequisites · Checked 2026-09-25
- 14HTTPS-networked locations exchange directory data over HTTP on TCP port 8081 or HTTPS on TCP port 8444, and exchange voice messages over SMTP on TCP port 25, either directly or through a smart host.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > prerequisites · Checked 2026-09-25
- 15HTTPS networking supports only a single-site network; multiple HTTPS networks cannot be connected to one another.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Designing a Unity Connection Network using HTTPS · Checked 2026-09-25
- 16In HTTPS networking the directory-data and recorded-name synchronisation tasks are enabled by default and run every 15 minutes.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > directory synchronization tasks · Checked 2026-09-25
- 17Cisco's HTTPS network setup task list links the servers, then configures smart hosts and SMTP access for cluster subscribers, then verifies replication, and only after that configures search spaces, security, cross-server features and testing.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > task list for setting up an HTTPS network · Checked 2026-09-25
- 18Initial directory replication between newly linked locations can take from a few minutes to a few hours, depending on directory size.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > verifying replication · Checked 2026-09-25
- 19For an intersite link, one location in each site acts as site gateway, and all directory synchronisation and voice messages between the two sites pass between those gateways.Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > intersite networking · Checked 2026-09-25
- 20An intersite link joins exactly two Unity Connection sites, raising the maximum from ten locations to twenty; no more than two sites can be linked.Networking Guide for Cisco Unity Connection Release 15 - Setting Up Networking Between Cisco Unity Connection Servers · Setting Up Networking Between Cisco Unity Connection Servers > site limitations · Checked 2026-09-25
- 21Intersite networking is not supported with Cisco Business Edition.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Intersite Networking between Two Unity Connection Sites · Checked 2026-09-25
- 22System contacts, system distribution list membership and VPIM locations and contacts are not replicated between sites over an intersite link.Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > replication between sites · Checked 2026-09-25
- 23A site can have only one intersite link, so it cannot link to another Unity Connection site and to a Cisco Unity site at the same time.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Intersite Networking between Two Unity Connection Sites · Checked 2026-09-25
- 24By default, the intersite Reader polls the remote Feeder every 15 minutes, with separate tasks for directory data and recorded names.Networking Guide for Cisco Unity Connection Release 15 - Setting Up Networking Between Cisco Unity Connection Servers · Setting Up Networking Between Cisco Unity Connection Servers > intersite synchronization · Checked 2026-09-25
- 25The two intersite gateways exchange directory updates over HTTP on port 80 or HTTPS on port 443, and exchange messages over SMTP on port 25, either directly or through a smart host.Networking Guide for Cisco Unity Connection Release 15 - Setting Up Networking Between Cisco Unity Connection Servers · Setting Up Networking Between Cisco Unity Connection Servers > prerequisites for linking sites · Checked 2026-09-25
- 26The Release 15 networking guide and system requirements say every server in both sites must run Unity Connection version 15 before two sites can be linked.disputedNetworking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > intersite networking · Checked 2026-09-25
- 27The Release 15 design guide says all Unity Connection locations in a site must run release 8.0 or later for intersite networking.disputedDesign Guide for Cisco Unity Connection 15 - Networking · Networking > Intersite Networking between Two Unity Connection Sites · Checked 2026-09-25
- 28The Release 15 design guide's intrasite section contains the sentence 'Intrasite networking is supported only with Cisco Business Edition 6000/7000'.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Intrasite Networking · Checked 2026-09-25
- 29A legacy Unity Connection site (intrasite networking) can contain at most ten Unity Connection servers or clusters, called locations.Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > intrasite networking · Checked 2026-09-25
- 30Within an intrasite network, every location uses SMTP to exchange both directory synchronisation information and voice messages directly with every other location.Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > intrasite networking · Checked 2026-09-25
- 31In legacy (intrasite/intersite) networking the global directory limit is 100,000 users and system contacts combined, with the same limits on distribution lists as HTTPS networking.Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > directory size limits · Checked 2026-09-25
- 32In a Unity Connection network, objects can belong only to local partitions (remote partitions can still be added to local search spaces), and system call handler owners must be local users.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Overview of HTTPS Networking · Overview of HTTPS Networking > partitions, search spaces and object ownership · Checked 2026-09-25
- 33Message recall does not work between sites linked by an intersite link.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Intersite Networking between Two Unity Connection Sites · Checked 2026-09-25
- 34Migrating from legacy to HTTPS networking requires a downtime window, and its length depends on the number of locations and the directory size.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Migration from Legacy Network to HTTPS Network · Migration from Legacy Network to HTTPS Network > overview · Checked 2026-09-25
- 35The only supported way to migrate from legacy networking to HTTPS networking is manual; there is no automated migration tool.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Migrating from Legacy (SMTP) Networking to HTTPS Networking · Checked 2026-09-25
- 36Before migrating from legacy networking to HTTPS networking, all locations must be upgraded to Release 15, replication must be healthy and in sync with none stalled, and every location must be backed up.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Migration from Legacy Network to HTTPS Network · Migration from Legacy Network to HTTPS Network > prerequisites · Checked 2026-09-25
- 37The flash-cut migration backs up distribution lists with the Distribution List Syncher, unjoins every location from the legacy network, takes a DRS backup, joins the locations in the HTTPS topology, enables distribution-list sync and then restores the lists.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Migration from Legacy Network to HTTPS Network · Migration from Legacy Network to HTTPS Network > migration steps · Checked 2026-09-25
- 38Legacy (SMTP) networking and HTTPS networking cannot run at the same time in the same network.Design Guide for Cisco Unity Connection 15 - Networking · Networking > Designing a Unity Connection Network using HTTPS · Checked 2026-09-25
- 39After a location is removed from an HTTPS network, the 'Remove Objects Associated With Deleted Network Location' task purges its objects; by default it runs daily at 10:00 p.m., and Cisco recommends keeping that schedule.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Making Changes to HTTPS Networking Configuration · Making Changes to HTTPS Networking Configuration > removing a location · Checked 2026-09-25
- 40SAML SSO cannot be used to access all the nodes of an HTTPS, intrasite or intersite network.System Requirements for Cisco Unity Connection Release 15 · Requirements for HTTPS / Intrasite / Intersite Networking · Checked 2026-09-25
- 41If RTMT raises a NetworkLoopDetected alert, Cisco says to find the loop with the Network Analyzer tool and then unjoin and rejoin the affected locations in the correct hierarchy.Troubleshooting Guide for Cisco Unity Connection Release 15 - Troubleshooting Networking · Troubleshooting Networking > network loop detection · Checked 2026-09-25
- 42When an SSL-enabled HTTPS link is created, Unity Connection checks that the IP address, FQDN or hostname entered matches the remote location's web SSL certificate; if not, enter the matching value or tick 'Ignore Certificate Errors'.Troubleshooting Guide for Cisco Unity Connection Release 15 - Troubleshooting Networking · Troubleshooting Networking > HTTPS link creation errors · Checked 2026-09-25
- 43The CLI command 'utils cuc networking synchttps' resynchronises selected data across an HTTPS link or location, by USN (up to 10 per command), by object type, or by recorded voice name.Troubleshooting Guide for Cisco Unity Connection Release 15 - Troubleshooting Networking · Troubleshooting Networking > selective synchronization · Checked 2026-09-25
- 44To check replication, compare the Last USN Sent, Received and Acknowledged fields on the Edit Unity Connection Location page; if they stop incrementing, replication may be stalled, and the system re-requests records after a default five-minute timeout.Troubleshooting Guide for Cisco Unity Connection Release 15 - Troubleshooting Networking · Troubleshooting Networking > directory replication (USN fields; stalled replication) · Checked 2026-09-25
- 45A server whose display name or SMTP domain matches that of another server already in the network cannot join the network.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network · Setting Up an HTTPS Network > verifying display names and SMTP domains · Checked 2026-09-25
- 46The Release 15 HTTPS Networking Guide lists the HTTPS network directory limit as 100,000 users.disputedHTTPS Networking Guide for Cisco Unity Connection Release 15 - Overview of HTTPS Networking · Overview of HTTPS Networking > Directory Size Limits · Checked 2026-09-25
- 47The Release 14 HTTPS Networking Guide lists 160,000 users as the directory limit and notes that 14SU2 and earlier support 100,000 users.HTTPS Networking Guide for Cisco Unity Connection Release 14 - Overview of HTTPS Networking · Overview of HTTPS Networking > Directory Size Limits · Checked 2026-09-25
- 48The Release 15 design guide states that from Unity Connection 14SU3 onward the network directory limit for users is 160,000.disputedDesign Guide for Cisco Unity Connection 15 - Networking · Networking > Designing a Unity Connection Network using HTTPS · Checked 2026-09-25
- 49The 100,000-user figure in the Release 15 HTTPS guide is probably text left over from before 14SU3 rather than a lower Release 15 limit.inferredHTTPS Networking Guide for Cisco Unity Connection Release 14 - Overview of HTTPS Networking · Overview of HTTPS Networking > Directory Size Limits (compared against the Release 15 guide section of the same name) · Checked 2026-09-25
- 50Legacy networking tracks directory changes with Unique Sequence Numbers (USNs): each change increments the location's USN by one and is recorded in its database.Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts · Overview of Networking Concepts > USNs and replication sets · Checked 2026-09-25
- 51Cisco recommends choosing one location in a site as the bridgehead that holds the configuration for VPIM locations and contacts.Design Guide for Cisco Unity Connection 15 - Networking · Networking > VPIM Networking · Checked 2026-09-25
- 52Unity Connection VPIM networking uses VPIM version 2 (RFC 3801) over SMTP and MIME, and works with third-party voice messaging systems that support VPIM version 2.Design Guide for Cisco Unity Connection 15 - Networking · Networking > VPIM Networking · Checked 2026-09-25
- 53Cross-server handoffs are signalled in-band: the originating location holds the caller, dials the receiving location with the cross-server dial string, and the two locations exchange DTMF tone sequences before the call is handed off.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking · Cross-Server Sign-In > how it works; Cross-Server Transfer > how it works · Checked 2026-09-25
- 54Cross-server sign-in needs 'Respond to Cross-Server Handoff Requests' enabled on the receiving location, plus 'Allow Cross-Server Sign-In to this Remote Location' and a cross-server dial string on the originating location.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking · Cross-Server Sign-In > task list · Checked 2026-09-25
- 55If identified subscriber messaging is disabled, cross-server live reply works only for messages that users sent after signing in to their mailboxes.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking · Cross-Server Live Reply · Checked 2026-09-25
- 56Only one cross-server dial string can be entered per receiving location, so an originating location with several phone system integrations needs a dial string that all of them can use.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking · Cross-Server Sign-In > dial string limitation · Checked 2026-09-25
- 57A shortage of available voice messaging ports can stop cross-server transfers; Cisco suggests checking port use with the Unity Connection Port Usage Analyzer.Troubleshooting Guide for Cisco Unity Connection Release 15 - Troubleshooting Networking · Troubleshooting Networking > cross-server sign-in and transfer problems · Checked 2026-09-25
- 58Cisco recommends configuring the same search scope on the originating and receiving locations, because a match found on one location's scope may not be found on the other's.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking · Cross-Server Transfer > search scope considerations · Checked 2026-09-25
- 59Enabling cross-server transfer automatically enables cross-server live reply for users whose class of service allows live reply.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking · Cross-Server Live Reply · Checked 2026-09-25
- 60When two locations are linked by an HTTPS link, a video call that uses a cross-server feature is downgraded to audio.HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking · Cross-Server Sign-In / Transfers / Live Reply > video call notes · Checked 2026-09-25
Documents
Design Guide for Cisco Unity Connection 15 - Networking
HTTPS Networking Guide for Cisco Unity Connection Release 14 - Overview of HTTPS Networking
HTTPS Networking Guide for Cisco Unity Connection Release 15 - Cross-Server Sign-In, Transfers, and Live Reply in HTTPS Networking
HTTPS Networking Guide for Cisco Unity Connection Release 15 - Making Changes to HTTPS Networking Configuration
HTTPS Networking Guide for Cisco Unity Connection Release 15 - Migration from Legacy Network to HTTPS Network
HTTPS Networking Guide for Cisco Unity Connection Release 15 - Overview of HTTPS Networking
HTTPS Networking Guide for Cisco Unity Connection Release 15 - Setting Up an HTTPS Network
Networking Guide for Cisco Unity Connection Release 15 - Overview of Networking Concepts
Networking Guide for Cisco Unity Connection Release 15 - Setting Up Networking Between Cisco Unity Connection Servers
System Requirements for Cisco Unity Connection Release 15
Troubleshooting Guide for Cisco Unity Connection Release 15 - Troubleshooting Networking
Cite this page
APA
WarmTransfer. (2026, September 25). Unity Connection networking. WarmTransfer. https://warmtransfer.net/knowledge/unity-connection-networking
BibTeX
@misc{warmtransfer-unity-connection-networking,
title = {Unity Connection networking},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/unity-connection-networking},
note = {Verified 2026-09-25}
}