This article explains how to use Office Mode to avoid tunnel-in-tunnel traffic when remote users are located behind a site.
Overview
Office Mode optimizes Client performance when users with a ZTNA license are physically located in a branch office. It avoids tunnel-within-a-tunnel scenarios by seamlessly routing traffic through the local site instead of the Client's encrypted tunnel. This reduces latency and simplifies traffic routing. You can configure Office Mode globally or allow users to enable or disable it manually in the Client.
Use the Advanced Configuration page to manage Office Mode behavior:
For all users in the account: go to Resources > Advanced Configuration
For an individual user: go to User Configuration > Advanced Configuration
Prerequisites
Send HTTPS requests over TCP port 443 to the Cato tunnel API services:
tunnel-api.catonetworks.comtunnel-ws-api.catonetworks.com
How Office Mode Works
Office Mode first detects whether the device is behind a Socket or IPsec site. If it is, and the configuration allows it, the Client operates in Office Mode and uses the site tunnel to the PoP.
When Office Mode is enabled, and the Client detects a direct connection to a site:
The Client tunnel is bypassed
All traffic routes through the site’s tunnel to the PoP
The site’s security policy is enforced instead of the Client policy
Office Mode Behavior for Always-On Users
For Client resiliency, there are scenarios where the Client maintains a tunnel to the PoP even in Office Mode. The Client is not sending data over this tunnel.
macOS Clients always maintain a tunnel using UDP
Windows Clients with Require auth in Office setting enabled always maintain a tunnel using UDP
For more about the Require auth in Office setting, see this article.
What Happens When Office Mode Is Disabled
If the user disables Office Mode while connected to the local site:
All traffic, including local LAN traffic, is routed through the Client’s encrypted tunnel
Local traffic is sent to the PoP and then back to the site, increasing latency
The security policy for the user identity is enforced instead of the site policy
Automatic Connection Behind a Site (Windows, macOS, and Linux)
Starting in Windows Client v5.10, macOS v5.11 and Linux Client v5.2:
The Client automatically connects behind a site without requiring user authentication
The Connect button is disabled while behind the site
Office Mode is enforced to avoid redundant tunnels
This simplifies the user experience and enforces consistent routing policies. For more information, see Using Cato Identity Agents for User Awareness
Using Office Mode with a Private DNS Server
For accounts that use a private DNS server, you must make these configuration changes:
Add the following DNS entry to the private DNS server to support Client office mode:
vpn.catonetworks.netas IP address 10.254.254.5 (or the customized reserved service range x.y.z.2 IP address)tunnel-api.catonetworks.comas IP address 10.254.254.3 (or the customized reserved service range x.y.z.7 IP address)
Note: You must also ensure that your firewall is configured to allow traffic to these addresses for Office Mode to function properly.
For configurations where the private DNS server is located on the local LAN, then the static DNS entry and the connectivity over the local LAN means that the SDP users are always identified as being connected with office mode. Even if the site (and the SDP users in office mode) aren't connected to the Cato Cloud, because the SDP users have connectivity to the private DNS server, they are shown as being connected using office mode.
Allowing Users to Configure Office Mode
By default, users cannot enable or disable Office Mode. You can configure this behavior globally or override it per user.
Status is Disabled (Default global setting) - Office mode is enabled for all users, and they can't configure office mode in their specific Clients.
Status is Enabled and Value is On - All SDP users in the account can choose to enable or disable office mode for their Client.
Status is Enabled and Value is Off - Office mode is enabled for all users, and they can't configure office mode in their specific Clients. This functionality is the same as Disabled.
Global Configuration: Allow Users to Control Office Mode
To allow all users in an account to control Office Mode:
From the navigation menu, select Resources > Advanced Configuration
In the Office Mode Configuration section, configure these fields:
Status
Disabled – Users cannot change Office Mode, and it is enabled (default)
Enabled – Users can control Office Mode, based on the Value field
Value
On – Office Mode is enabled by default, but users can disable it
Off – Users can't disable Office Mode
Per-User Configuration
You can allow individual users to override the global setting.
To configure Office Mode per user:
From the navigation menu, select Users and choose a user.
From the user configuration panel, go to Advanced Configuration:
In the Office Mode Configuration section, configure these fields:
Status - set to Enabled
Value
On – Office Mode is enabled by default, but users can disable it
Off – Office Mode is disabled and users cannot enable it
This setting only applies when the user connects behind a site.
Disabling or Enabling Office Mode in the Client
After the configuration is applied, users can change the setting in the Cato Client.
To enable or disable Office Mode:
Connect the Client to ensure it receives the latest configurationץ
If already connected, disconnect and reconnect.
Open the Settings panel in the Client.
Locate the SDP Office Mode option.
Toggle the checkbox to enable or disable Office Mode.
Reconnect the Client to apply the change.
Known Limitations
Office mode is only supported with a UDP connection