The documentation set for this product strives to use bias-free language. For the purposes of this documentation set, bias-free is defined as language that does not imply discrimination based on age, disability, gender, racial identity, ethnic identity, sexual orientation, socioeconomic status, and intersectionality. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. Learn more about how Cisco is using Inclusive Language.
The following major Expressway-based deployments do not work together. They cannot be implemented together on the same Expressway (or traversal pair):
Mobile and Remote Access
Microsoft interoperability, using the Expressway-C-based B2BUA
Jabber Guest services
This section describes the supported deployment environments:
Single network elements
Single clustered network elements
Multiple clustered network elements
Hybrid deployment
 Note |
The only supported Mobile and Remote Access deployments are based on one-to-one Unified Communications zones between Expressway-C clusters and Expressway-E clusters. |
In this scenario there are single (non-clustered) Unified CM, IM and Presence Service, Expressway-C, and Expressway-E servers.
In this scenario each network element is clustered.
In this scenario there are multiple clusters of each network element.
Jabber clients can access their own cluster through any route.
Expressway-C uses round robin to select a node (publisher or subscriber) when routing home cluster discovery requests.
Each combination of Unified CM and IM and Presence Service clusters must use the same domain.
Intercluster Lookup Service (ILS) must be active on the Unified CM clusters.
Intercluster peer links must be configured between the IM and Presence Service clusters, and the Intercluster Sync Agent (ICSA) must be active.
In this scenario, IM and Presence Service for Jabber clients are provided via the Webex cloud.
VPN links, between the Expressway-C and the Unified CM services / clusters, are not supported.
"Mixed" traversal connections are not supported. That is, we do not support traversal zones, or Unified Communications traversal zones, between Cisco VCS and Cisco Expressway even though it is possible to configure these zones.
Explicitly, we do not support VCS Control traversal to Expressway-E, nor do we support Expressway-C traversal to VCS Expressway.
We do not support Unified Communications zones from one Expressway-C cluster to multiple unclustered Expressway-Es.
We also do not support multiple Unified Communications zones from one Expressway-C cluster to multiple Expressway-Es or Expressway-E clusters.
MRA is not currently supported over chained traversal connections (using multiple Expressway-Es to cross multiple firewalls).
This means that you cannot use Expressway-E to give Mobile and Remote Access to endpoints that must traverse a nested perimeter network to call internal endpoints.
We do not support Expressway-C in a DMZ that uses static NAT. This is because the Expressway-C does not perform the SDP rewriting that is required to traverse static NAT-enabled firewalls. You should use the Expressway-E for this purpose.
You could potentially place the Expressway-C in a DMZ that does not use static NAT, but we strongly discourage this deployment because it requires a lot of management on the inmost firewall. We always recommend placing the Expressway-C in the internal network.
Feedback