{"id":7420,"date":"2026-02-26T11:54:44","date_gmt":"2026-02-26T10:54:44","guid":{"rendered":"https:\/\/onlu.ch\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\/"},"modified":"2026-05-05T15:25:19","modified_gmt":"2026-05-05T13:25:19","slug":"teams-alternative-without-cloud-connectivity-for-on-prem-hosting","status":"publish","type":"post","link":"https:\/\/onlu.ch\/en\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\/","title":{"rendered":"Teams alternative without cloud connectivity for on-prem hosting"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">The requirement &#8220;completely without cloud connectivity&#8221; effectively excludes Microsoft Teams because Microsoft Teams is designed as a SaaS\/cloud service and does not provide an on-premises version. This shifts the problem from &#8220;which tool is similar?&#8221; to &#8220;which system can be operated <strong>technically, organizationally and regulatory<\/strong> in such a way that <strong>no third-party cloud services<\/strong> (incl. push gateways, telemetry\/registration, marketplace access, update dependencies) are necessary in productive operation&#8221;. <\/p>\n\n<p class=\"wp-block-paragraph\">For a bank setting (strict traceability, identity integration, audit\/retention, HA\/DR, controlled changes), two realistic top candidates emerge if &#8220;no cloud&#8221; is interpreted <strong>strictly<\/strong>:<\/p>\n\n<p class=\"wp-block-paragraph\">Many self-hosted solutions deliver push via provider gateways or via Apple\/Google push services (APNs\/FCM), both of which are strictly speaking &#8220;third-party providers&#8221;. This must either be (a) consciously deactivated\/accepted, (b) solved by an explicitly air-gapped product or (c) compensated for via alternative mobile strategies (e.g. MDM policies, &#8220;always-on&#8221; clients, possibly Android without Google services) (not specified).    <\/p>\n\n<h2 class=\"wp-block-heading\" id=\"kontext-und-anforderungen\">Context and requirements<\/h2>\n\n<h3 class=\"wp-block-heading\" id=\"ausgangslage-und-harte-randbedingung\">Initial situation and hard boundary condition<\/h3>\n\n<p class=\"wp-block-paragraph\">A bank needs a replacement for Microsoft Teams that can be operated <strong>completely without cloud connectivity<\/strong>: on-premises or completely self-hosted, without dependence on third-party cloud services. (Interpretation: no part of operations &#8211; not even push, license sync, marketplace, telemetry, TURN-as-a-Service &#8211; must necessarily go to the Internet\/vendor cloud. This interpretation is to be understood as an assumption because the &#8220;no cloud policy&#8221; is not specified in detail). <\/p>\n\n<p class=\"wp-block-paragraph\">The fact that Microsoft Teams itself does not offer an on-premises server version is the key driver for an alternative platform.  <\/p>\n\n<h3 class=\"wp-block-heading\" id=\"funktionsumfang-der-im-bankkontext-typischerweise-teamskritisch-ist\">Functional scope that is typically &#8220;team-critical&#8221; in the banking context<\/h3>\n\n<p class=\"wp-block-paragraph\">The attributes you mentioned can be translated into must\/should clusters typical for banks:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>Identity &amp; access<\/strong>: AD\/LDAP integration, SSO (SAML\/OIDC), roles\/privileges, SCIM provisioning if necessary.  <\/li>\n\n\n\n<li><strong>Communication<\/strong>: 1:1\/group chat, persistent &#8220;channels\/streams&#8221; incl. threads, search, file attachments; audio\/video meetings, screen sharing.   <\/li>\n\n\n\n<li><strong>Compliance<\/strong>: Audit logs, retention\/legal hold\/eDiscovery\/export capability. (Teams uses Microsoft Purview for this; in an on-prem setting, equivalents or SIEM\/archive integration are required).   <\/li>\n\n\n\n<li><strong>Operation &amp; resilience<\/strong>: HA (node redundancy), backup\/restore, disaster recovery plan, monitoring, patch\/update process also offline.  <\/li>\n\n\n\n<li><strong>End devices<\/strong>: Windows\/macOS\/Linux, iOS\/Android, web client + browser support.  <\/li>\n<\/ul>\n\n<h3 class=\"wp-block-heading\" id=\"nicht-spezifiziert-wird-im-report-explizit-als-offen-markiert\">Not specified (will be explicitly marked as open in the blog)<\/h3>\n\n<p class=\"wp-block-paragraph\">Several decisive parameters are not defined in the request and strongly influence the architecture, costs and product selection: number of users, simultaneous meeting load, external federation\/partner access (Internet\/DMZ yes\/no), retention periods, eDiscovery process (internal\/external), MDM stack, network segmentation and degree of integration in Exchange\/Outlook (pure invitation template vs. real presence\/calendar integration).<\/p>\n\n<h2 class=\"wp-block-heading\" id=\"kandidatenanalyse\">Candidate analysis<\/h2>\n\n<p class=\"wp-block-paragraph\">The solutions you have prioritized are evaluated below &#8211; with a focus on &#8220;fully offline\/on-prem&#8221; as a hard guard rail.<\/p>\n\n<h3 class=\"wp-block-heading\" id=\"skype-for-business-server-subscription-edition-als-microsoftonprempfad\">Skype for Business Server (Subscription Edition) as &#8220;Microsoft On-Prem&#8221; path<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: On-premises UC platform with IM\/presence, conferencing and optional persistent chat (permanent chat rooms).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Deployment<\/strong>: Classic on-prem (pools\/edge). Federation\/external access is typically provided via edge servers (DMZ-capable, policy-controlled).   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Team coverage<\/strong>:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>Strengths: Presence, classic enterprise voice\/conferencing tradition, SIP federation.  <\/li>\n\n\n\n<li>Gaps compared to Teams: &#8220;Modern Work Hub&#8221; (apps\/workflows), file collaboration such as SharePoint\/OneDrive ecosystem, UX expectations. <\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\"><strong>Compliance\/Archiving<\/strong>: Persistent Chat Server stores content permanently (text\/links\/files in the chat context), which can support compliance requirements, but is functionally different from Teams channels.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>License\/support reality<\/strong>: Subscription Edition requires active Software Assurance or suitable subscription licenses; Microsoft thus positions the on-prem server products as &#8220;version-less&#8221; with Modern Lifecycle Updates.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank <\/strong>Very good if the focus is on <strong>maximum Microsoft on-prem continuity<\/strong> (AD\/Exchange proximity, classic UC). Weaker if a &#8220;Teams-like&#8221; channel\/app model and modern collaboration are expected. <\/p>\n\n<h3 class=\"wp-block-heading\" id=\"mattermost-selfhosted\">Mattermost (self-hosted)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Team messaging with channels, strong admin\/compliance focus and integrated calls (plugin).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Deployment<\/strong>: Self-hosted; enterprise features for compliance and HA clustering.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Audio\/Video<\/strong>: Calls plug-in; default participant limit is configurable, practical recommendation up to ~50 per call depending on resources (important operational note for bank meetings\/all-hands).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Compliance\/eDiscovery<\/strong>: Explicitly documented for compliance monitoring, retention and eDiscovery export; connection to archive\/eDiscovery third-party systems (e.g. Smarsh, Global Relay, Proofpoint) is mentioned.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>HA\/DR<\/strong>: HA cluster deployment available (Enterprise); however, no HA topology supported across multiple data centers (important for true active-active DR).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Clients<\/strong>: Desktop app for Windows\/macOS\/Linux; web experience available.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Security\/Certifications<\/strong>: Official Trust area lists SOC 2 Type II (2025) and ISO 27001 (2022) as available artifacts (vendor-side).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Costs (ball park, estimate)<\/strong>:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>License: Enterprise subscription (prices usually subject to quotation; varies according to user tier\/support).<\/li>\n\n\n\n<li>Infrastructure: typically 3+ app nodes + DB cluster + object\/file store; depending on the number of users and call load from &#8220;few VMs&#8221; (pilot) to &#8220;dedicated cluster resources&#8221; (rollout).<br \/>(Bandwidth deliberately as an estimate, as public prices are not standardized and strongly dependent on load\/SLA).<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank<\/strong>: Very strong for <strong>internal operations<\/strong> with audit\/retention\/discovery and clear operating processes; meetings &gt;50 participants should be tested early in a performance proof or supplemented via external\/additional meeting components (e.g. on-prem video).  <\/p>\n\n<h3 class=\"wp-block-heading\" id=\"rocketchat-selfhosted-inkl-airgapped-modus\">Rocket.chat (self-hosted, incl. &#8220;air-gapped&#8221; mode)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Collaboration platform with messaging, voice\/video, compliance controls, Kubernetes scaling and E2EE options.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Deployment<\/strong>: Self-managed (Docker\/Kubernetes) and explicitly documented &#8220;air-gapped workspace&#8221;; microservices architecture is recommended for greater concurrency.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Compliance<\/strong>:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>Audit Logs\/Message Auditing Panel documented (Enterprise functions).  <\/li>\n\n\n\n<li>Retention policies available (messages are otherwise &#8220;never&#8221; deleted).  <\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\"><strong>E2EE<\/strong>: Workspace-wide activation possible; encrypted rooms possible. <br \/>Bank trade-off: E2EE can make auditing\/discovery more difficult if auditors have to track content on the server side (this conflict of objectives is conceptual).<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Push notifications as a no-cloud risk<\/strong>: Default gateway is gateway.rocket.chat; documentation also indicates cloud terms\/registration, and direct communication to Apple\/Google (APNs\/FCM) takes place when the gateway is deactivated. This collides with &#8220;no third-party provider&#8221; or &#8220;no Internet&#8221;.   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Update\/support window<\/strong>: Rocket.Chat documents that versions are only supported for a limited period of time (EOL window); this increases operational patch pressure, which often increases change window\/validation effort in banks.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Security\/Certifications<\/strong>: ISO 27001 is reported in the compliance area (scope according to documentation); Rocket.Chat also communicates SOC 2 Type II as a current achievement (Feb 2026).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for bank<\/strong>: Strong for messaging + compliance control; if <strong>strictly offline<\/strong>, push\/registration\/marketplace dependencies must be designed particularly carefully (e.g. mobile strategy without push or with strictly controlled exception).  <\/p>\n\n<h3 class=\"wp-block-heading\" id=\"element-server-suite-matrixsynapse--souver&#xE4;n-und-airgapped\">Element Server Suite (Matrix\/Synapse) &#8211; sovereign and air-gapped<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Matrix-based enterprise suite (server + clients + conferencing via Element Call), explicitly for digital sovereignty and isolated networks. Matrix is shaped by The Matrix.org Foundation as an open standard; Synapse is maintained by Element in accordance with the project notes (note the license\/maintenance reality).   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Air-gapped\/offline capability<\/strong>: Element explicitly positions the Sovereign\/air-gapped offer as &#8220;no internet required&#8221; &#8211; including installation, updates and notifications; a &#8220;custom mobile push gateway&#8221; option is also mentioned.   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Identity\/SSO<\/strong>: Delegated Authentication supports LDAP\/SAML\/OIDC (described in ESS documentation).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Conferencing<\/strong>: Element Call is described as a conference component with a claim to scale (multi-SFU architecture, &#8220;sovereignty&#8221; argumentation).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Compliance controls<\/strong>: Pricing\/feature overview names Retention Policies, Auditing\/Reporting and Data Export as enterprise functions.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Backup\/DR<\/strong>: Element documents backup &amp; restore and names critical components for DR (PostgreSQL DB, keys, Auth-DB etc.).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Security\/Certifications<\/strong>: Element communicates ISO\/IEC 27001:2022 certification (blog\/price page).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Costs (ball park, estimate)<\/strong>:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>ESS Pro is priced &#8220;per seat\/month&#8221;, Sovereign &#8220;per deployment&#8221; (offer model).  <\/li>\n\n\n\n<li>Infrastructure: typically Kubernetes-based (or standalone), Postgres + persistent volumes; additional components for federation control\/border gateway depending on security domains.  <\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for bank<\/strong>: Very high if &#8220;no cloud&#8221; and <strong>isolated networks<\/strong> are really leading and modern messenger\/channel functionality + conferences are required at the same time. Particularly relevant if external federation\/partner communication is desired in the future (matrix federation model, controllable).   <\/p>\n\n<h3 class=\"wp-block-heading\" id=\"nextcloud-talk--nextcloud-hub-files--talk--groupware\">Nextcloud Talk \/ Nextcloud Hub (Files + Talk + Groupware)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Collaboration platform with a strong focus on files\/sharing; Talk offers chat + audio\/video incl. screen sharing.   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Deployment<\/strong>: on-prem\/private cloud. Talk is explicitly positioned as on-prem\/private collaboration.   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Files &amp; on-prem file server integration<\/strong>: External Storage supports SMB\/CIFS file servers, among others; admin documentation describes SMB integration.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Meetings &amp; scaling<\/strong>: Talk High Performance Backend (HPB) includes signaling + WebRTC gateway; Talk scalability documentation describes with HPB typically 30-50 active participants and hundreds of passive (bandwidth limited).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>E2EE<\/strong>: Nextcloud documents E2EE primarily for files (client-side). <br \/>There is a &#8220;call-end-to-end-encryption&#8221; capability for Talk (off by default until all mobile clients support it). <br \/>According to community statements, E2EE is currently not available for Talk text messages (secondary source, to be understood as a risk\/limit).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Audit\/logging<\/strong>: Admin manual mentions logging and optionally the admin_audit app for extended event logging.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Vendor support, SLA &amp; price reference (transparent)<\/strong>: Nextcloud publishes specific \u20ac\/user\/year prices, response times and optional Talk subscriptions (e.g. Talk from \u20ac42\/user\/year, Files tiers from ~\u20ac71\/user\/year; support response times per tier).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>No-cloud risk: push notifications<\/strong>: Nextcloud describes push notifications via a &#8220;Nextcloud Push Proxy&#8221; (free hosted service from Nextcloud). This is a potential show-stopper for strictly &#8220;no-cloud&#8221; users if mobile push is absolutely necessary. <br \/>(Note: There is a portal article &#8220;On premise push proxy server&#8221;, the detailed content of which is not publicly accessible; feasibility\/product maturity for a bank <strong>can<\/strong> therefore <strong>not be verified<\/strong> in this blog).   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank<\/strong>: Very good if the focus is on <strong>file collaboration with on-prem storage integration<\/strong> and Talk is &#8220;good enough&#8221; as a communication layer &#8211; with the central open question of how mobile push should be solved &#8220;cloud-free&#8221;.  <\/p>\n\n<h3 class=\"wp-block-heading\" id=\"jitsi-onprem-videoconferencing\">Jitsi (on-prem video conferencing)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Open source WebRTC video conferencing, self-hostable (Debian\/Ubuntu Quickstart).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Deployment<\/strong>: Own Jitsi Meet stack; suitable as a &#8220;meeting engine&#8221; in addition to chat platforms.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Security\/E2EE<\/strong>: Jitsi describes optional end-to-end encryption in browsers with insertable streams (Chromium-based browsers; also Electron client).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Clients\/Browsers<\/strong>: Documented browser support, incl. iOS special features.   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank<\/strong>: Strong as a <strong>pure conference module<\/strong> on-prem; unsuitable as a complete Teams replacement (not a fully-fledged channel\/compliance system).<\/p>\n\n<h3 class=\"wp-block-heading\" id=\"cisco-meeting-server--cisco-im--presence-onprem-ucstack\">Cisco Meeting Server + Cisco IM &amp; Presence (On-Prem UC stack)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Premises-based meetings (Cisco Meeting Server) plus IM\/Presence (Cisco Unified Communications Manager IM &amp; Presence).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Browser\/WebRTC<\/strong>: Cisco Meeting Server Web App allows Join via WebRTC browser.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank<\/strong>: Very good for <strong>classic UC\/meetings<\/strong> on-prem; as a Teams replacement for Channels\/Files usually only useful in combination with an additional Chat\/Files platform.<\/p>\n\n<h3 class=\"wp-block-heading\" id=\"zulip-selfhosted-chatstreams\">Zulip (self-hosted chat\/streams)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Stream-based team chat (strong for asynchronous communication, threads), fully self-hostable.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>SSO<\/strong>: SAML-SSO is also documented for self-hosted.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Scaling\/requirements<\/strong>: Documentation specifies requirements and scaling instructions (e.g. 100+ users: 4 GB RAM\/2 CPUs as a guideline).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Limit<\/strong>: No native enterprise meeting suite like Teams; typically integration with Jitsi\/others for video.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank<\/strong>: Good for chat\/knowledge threads; as a full replacement only with an additional meeting stack.<\/p>\n\n<h3 class=\"wp-block-heading\" id=\"openfireprosody-xmpp-mit-plugins\">Openfire\/Prosody XMPP (with plugins)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: XMPP server (Openfire\/Prosody) as a basis for IM; can be extended via plugins\/clients.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Directory integration<\/strong>: Openfire documents AD\/LDAP integration.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Limit<\/strong>: Modern Team-UX (channels, files, eDiscovery, meeting scale) depends heavily on client ecosystem\/plugins; integration\/operational risk high.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank<\/strong>: Rather niche\/protection of existing business; only realistic as a team replacement with bank UX\/compliance requirements with considerable engineering performance.<\/p>\n\n<h3 class=\"wp-block-heading\" id=\"wire-onpremairgapped-secure-messenger\">Wire (on-prem\/air-gapped secure messenger)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Brief description<\/strong>: Secure messenger\/collaboration with E2EE for messages\/calls\/files; deployments incl. air-gapped possible (Wire for Governments).   <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>E2EE property<\/strong>: Wire says that messages\/calls are always E2EE and cannot be deactivated; key material remains on end devices.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>SSO\/provisioning<\/strong>: Wire documents SSO (SAML) and SCIM provisioning.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Compliance trade-off<\/strong>: &#8220;Always E2EE&#8221; can collide with eDiscovery\/archiving in the banking environment if the bank has to export content records in a legally compliant manner (not excluded, but organizationally\/technically demanding due to key ownership model).<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Clients<\/strong>: Wire offers downloads\/clients (iOS etc.).  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Suitability for a bank<\/strong>: Very good for &#8220;high-security messaging&#8221;\/crisis communication in isolated networks; potentially limited as a completely equivalent Teams replacement depending on compliance\/records obligations.  <\/p>\n\n<h2 class=\"wp-block-heading\" id=\"vergleich-und-bewertung\">Comparison and evaluation<\/h2>\n\n<h3 class=\"wp-block-heading\" id=\"featurematrix-vs-teams-fokussiert-auf-nocloudonprem\">Feature matrix &#8220;vs Teams&#8221; (focused on No-Cloud-On-Prem)<\/h3>\n\n<p class=\"wp-block-paragraph\">Legend: \u2705 = good\/integrated, \u26a0\ufe0f = possible but with restrictions\/additional components, \u274c = not primarily intended.<\/p>\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th class=\"has-text-align-left\" data-align=\"left\">Candidate<\/th><th class=\"has-text-align-right\" data-align=\"right\">Fully offline without third-party cloud (operation)<\/th><th class=\"has-text-align-right\" data-align=\"right\">Chat + persistent channels<\/th><th class=\"has-text-align-right\" data-align=\"right\">Audio\/video (suitable for meetings)<\/th><th class=\"has-text-align-right\" data-align=\"right\">Screen sharing<\/th><th class=\"has-text-align-right\" data-align=\"right\">File sharing + on-prem file server integration<\/th><th class=\"has-text-align-right\" data-align=\"right\">AD\/LDAP + SSO<\/th><th class=\"has-text-align-right\" data-align=\"right\">Audit\/Retention\/Discovery<\/th><th class=\"has-text-align-right\" data-align=\"right\">Clients (desktop\/mobile\/web)<\/th><\/tr><\/thead><tbody><tr><td>Skype for Business Server SE<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (on-prem)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (Persistent Chat as a separate role model)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Conferencing)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (not &#8220;Files-Hub&#8221; like Teams)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (MS ecosystem)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (different from Teams-Purview)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (Teams-other client model)<\/td><\/tr><tr><td>Mattermost (Enterprise)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (self-host)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (Calls, realistic recommendation ~50)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (attachment store; integration possible, but not SMB mount paradigm)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Enterprise-Auth)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Compliance Export\/Discovery)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">(desktop\/web; mobile via apps)  <\/td><\/tr><tr><td>Rocket.chat<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (air-gapped possible, but push\/cloud services critical)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\/\u26a0\ufe0f (depending on setup)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (files\/storage depending on backend)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Directory\/SSO usual)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Audit logs\/retention)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">(Win\/Mac\/Linux\/iOS\/Android\/Web)  <\/td><\/tr><tr><td>Element Server Suite (Sovereign)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (explicitly offline incl. updates\/notifications)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Element Call, E2EE)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Conferences)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (Media Repo; file server integration rather via links\/integrations)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">(LDAP\/OIDC\/SAML depending on the mode)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Auditing\/Retention\/Data Export)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">(Win\/macOS\/Linux\/iOS\/Android\/Web)  <\/td><\/tr><tr><td>Nextcloud Hub (Talk\/Files)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (on-prem yes; mobile push by default via Nextcloud Proxy)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (Conversations instead of Teams channels)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\/\u26a0\ufe0f (HPB recommended for Scale)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">(SMB\/CIFS External Storage)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">(Enterprise capabilities incl. SAML according to pricing)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (logging + admin_audit; eDiscovery to be built externally)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Desktop\/Mobile\/Web)  <\/td><\/tr><tr><td>Jitsi (on-prem)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u274c<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Video stack)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u274c\/\u26a0\ufe0f (no file hub function)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (Auth via Config\/SSO possible, not core here)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (meeting logs depending on the setup)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (browser + apps)  <\/td><\/tr><tr><td>Cisco Meeting Server + IM&amp;P<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (premises-based)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (IM&amp;P rather classic, channels different)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\/\u26a0\ufe0f (WebRTC Web App + Clients)  <\/td><\/tr><tr><td>Zulip<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705\u00a0<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Streams\/Topics)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u274c\/\u26a0\ufe0f (integration with meeting tool required)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (SAML self-hosted)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (export\/logs depending on setup)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Web + apps common; operation docs)  <\/td><\/tr><tr><td>Wire<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (called air-gapped deployments)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f (Rooms\/Teams, but Teams app hub is different)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (Calls\/Meetings)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (typical)<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f<\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (SSO\/SCIM)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u26a0\ufe0f\/\u274c (E2EE always-on makes classic eDiscovery more difficult)  <\/td><td class=\"has-text-align-right\" data-align=\"right\">\u2705 (iOS\/Android\/Desktop\/Web)  <\/td><\/tr><\/tbody><\/table><\/figure>\n\n<h3 class=\"wp-block-heading\" id=\"bewertungslogik-f&#xFC;r-bank-cic-qualitativ\">Valuation logic for a bank (qualitative)<\/h3>\n\n<p class=\"wp-block-paragraph\">If a bank (like many banks) needs <strong>verifiable records\/exports<\/strong>, a system with <strong>server-side controllable compliance exports<\/strong> is an advantage (Mattermost heavily documented; Rocket.Chat with audit\/retention; Element with retention\/auditing). <br \/>If, on the other hand, a bank primarily prioritizes <strong>maximum confidentiality<\/strong> through to isolated networks, the value of an explicitly air-gapped product (Element, Wire) increases.  <\/p>\n\n<p class=\"wp-block-paragraph\">The biggest technical &#8220;no-cloud&#8221; stumbling block remains <strong>mobile push<\/strong>: Nextcloud calls a hosted push proxy, Rocket.Chat calls a gateway and\/or APNs\/FCM, Matrix\/Element uses push gateway mechanisms (Sygnal \u2192 APNs\/FCM), whereby a strict offline interpretation either (a) disables push or (b) requires a product that explicitly covers notifications without internet.    <\/p>\n\n<h2 class=\"wp-block-heading\" id=\"empfehlung-und-implementierungsfahrplan\">Recommendation and implementation roadmap<\/h2>\n\n<h3 class=\"wp-block-heading\" id=\"finale-empfehlung\">Final recommendation<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>Recommendation 1: Element Server Suite (sovereign\/air-gapped) as a &#8220;hard no-cloud&#8221; primary solution<\/strong><br \/>Reason: Element explicitly addresses offline operation &#8220;end-to-end&#8221; (installation\/updates\/notifications without the Internet), offers enterprise controls (retention, auditing, admin tooling), identity integration (LDAP\/OIDC\/SAML depending on the mode) and a conferencing component (Element Call). <br \/><strong>Typical bank use cases<\/strong>: internal communication in isolated segments, secure exchange via defined rooms\/hierarchies, controlled federation optional (if later desired and approved), crisis communication in isolated company networks.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Recommendation 2: Mattermost (Enterprise self-hosted) as a &#8220;compliance-strong Teams replacement&#8221; for core operations<\/strong><br \/>Reason: Mattermost provides particularly clear compliance functionality (compliance monitoring, compliance export, eDiscovery export formats and integration notes), HA clusters in the data center and a pragmatic calls function including screen sharing (test under load assumptions).   <br \/><strong>Typical bank use cases<\/strong>: daily collaboration, team channels, incident\/ops communication, auditability, defined retention\/export pipelines in archive\/SIEM\/eDiscovery tooling.  <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Why not Nextcloud Talk as top 2?<\/strong><br \/>Nextcloud is very attractive as a files\/collaboration suite with transparent enterprise pricing and strong SMB integration, but the documented push proxy architecture (hosted) is in need of significant clarification under strict no-cloud interpretation &#8211; especially if iOS\/Android push is &#8220;must-have&#8221;.  <\/p>\n\n<h3 class=\"wp-block-heading\" id=\"implementierungsroadmap-phasen-grobe-timeline-pilotdesign\">Implementation roadmap (phases, rough timeline, pilot design)<\/h3>\n\n<p class=\"wp-block-paragraph\"><strong>&#8220;Preparation&#8221; phase (approx. 2-4 weeks)<\/strong><br \/>Goal: Finalize requirements and precisely operationalize &#8220;no cloud&#8221; (incl. mobile push policy), data classification per use case, retention\/discovery target picture, success metrics, target architecture (Prod\/DR) and operating model (DevSecOps vs. classic bank operation).<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Foundation Build phase (approx. 4-8 weeks)<\/strong><br \/>Objective: Set up the platform in a production-related staging zone incl. identity integration (LDAP\/SSO), logging\/audit pipeline, backup concept, monitoring, patch process. For Element: Backup\/DR according to ESS guidelines (DB\/Keys\/Auth). For Mattermost: Set up HA cluster and define upgrade runbooks (rolling upgrades).     <\/p>\n\n<p class=\"wp-block-paragraph\"><strong>&#8220;Pilot&#8221; phase (approx. 6-10 weeks)<\/strong><br \/>Target: Pilot with approx. 200-500 users (IT, operations, compliance stakeholders, 1-2 business units).<br \/>Focus:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>Functional coverage (chat\/channels, meetings + screen sharing, files)<\/li>\n\n\n\n<li>Performance under load (calls\/meetings; test the participant load early for Mattermost calls)  <\/li>\n\n\n\n<li>Compliance processes: Export test runs (Mattermost Compliance Export\/eDiscovery) \/ Audit workflows (Element Auditing\/Retention)  <\/li>\n\n\n\n<li>Security tests: hardening, threat model, pen test scope.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\"><strong>&#8220;Migration &amp; rollout&#8221; phase (approx. 8-16 weeks, in waves)<\/strong><br \/>Target: staggered rollout (e.g. 5-10% \u2192 30% \u2192 60% \u2192 100%), training, champions network, runbooks\/ITSM integration, deactivation\/restriction of team use cases.<\/p>\n\n<p class=\"wp-block-paragraph\"><strong>Stabilization &amp; Optimization&#8221; phase (ongoing)<\/strong><br \/>DR drills, incident playbooks, capacity planning, upgrades controlled in the bank change window.<\/p>\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"243\" src=\"https:\/\/onlu.ch\/wp-content\/uploads\/2026\/02\/image-1-1024x243.png\" alt=\"\" class=\"wp-image-6931\" srcset=\"https:\/\/onlu.ch\/wp-content\/uploads\/2026\/02\/image-1-1024x243.png 1024w, https:\/\/onlu.ch\/wp-content\/uploads\/2026\/02\/image-1-300x71.png 300w, https:\/\/onlu.ch\/wp-content\/uploads\/2026\/02\/image-1-768x182.png 768w, https:\/\/onlu.ch\/wp-content\/uploads\/2026\/02\/image-1-1536x364.png 1536w, https:\/\/onlu.ch\/wp-content\/uploads\/2026\/02\/image-1-2048x485.png 2048w, https:\/\/onlu.ch\/wp-content\/uploads\/2026\/02\/image-1-650x154.png 650w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n<h3 class=\"wp-block-heading\" id=\"erfolgskriterien-messbar\">Success criteria (measurable)<\/h3>\n\n<ul class=\"wp-block-list\">\n<li><strong>Security\/compliance<\/strong>: Audit trail complete (admin actions, export jobs), retention policies effective; eDiscovery exports reproducible and compliant (spot checks).  <\/li>\n\n\n\n<li><strong>Availability<\/strong>: HA failover without data loss; restore test after runbook successful (element: DB\/Keys\/Auth recovery; Mattermost: cluster failover in the data center).  <\/li>\n\n\n\n<li><strong>Performance<\/strong>: Defined meeting KPIs (join time, audio drop rate, screen share stability) met in pilot load profiles; participant limits explicitly validated for Mattermost calls according to resources.  <\/li>\n\n\n\n<li><strong>User adoption<\/strong>: defined activity metrics per unit (DAU\/WAU), support ticket rate decreases after wave 2; &#8220;Shadow IT&#8221; decline.<\/li>\n<\/ul>\n\n<h3 class=\"wp-block-heading\" id=\"migration-von-teams-pragmatische-strategie-statt-11import\">Migration of teams: pragmatic strategy instead of 1:1 import<\/h3>\n\n<p class=\"wp-block-paragraph\">A genuine 1:1 migration of historical Teams chats\/channels to a new platform is rarely loss-free in practice. Realistic approach: <\/p>\n\n<ol class=\"wp-block-list\">\n<li><strong>Export Teams data in a legally compliant manner and make it available as an archive<\/strong> (compliance\/eDiscovery export): Microsoft Purview eDiscovery allows the collection\/export of Teams content.  <\/li>\n\n\n\n<li><strong>Automated exports via Teams Export APIs<\/strong> (for defined scope\/periods) &#8211; especially for records management and transition periods.  <\/li>\n\n\n\n<li><strong>Cutover with coexistence<\/strong>: new projects\/channels in new system; old Teams artifacts read-only (policy).<\/li>\n\n\n\n<li><strong>Files<\/strong>: Migrate separately (because Teams files are located in different backends). Microsoft describes Teams as a hub in Microsoft 365; files are an integral part of the ecosystem and must therefore be systematically handled separately.   <\/li>\n<\/ol>\n\n<h2 class=\"wp-block-heading\" id=\"annahmen-und-offene-punkte\">Assumptions and open points<\/h2>\n\n<h3 class=\"wp-block-heading\" id=\"annahmen-im-report\">Assumptions in the blog<\/h3>\n\n<ul class=\"wp-block-list\">\n<li>&#8220;No-Cloud&#8221; was interpreted strictly: no vendor gateway, no mandatory registration\/telemetry, no dependency on APNs\/FCM or Nextcloud Push Proxy in productive target operation (unless explicitly approved as an exception).  <\/li>\n\n\n\n<li>The bank operates at least one own data center\/on-prem infrastructure with capability for HA clusters and regulated change processes (general bank assumption; not verified as fact).<\/li>\n<\/ul>\n\n<h3 class=\"wp-block-heading\" id=\"nicht-spezifizierte-anforderungen-entscheidungsrelevant\">Unspecified requirements (decision-relevant)<\/h3>\n\n<ul class=\"wp-block-list\">\n<li>Number of users (total) and peak concurrency (meetings\/calls, large townhalls).<\/li>\n\n\n\n<li>Whether external federation\/partner access is permitted (DMZ\/Internet) or must remain completely internal.<\/li>\n\n\n\n<li>Specific retention periods (e.g. years) and whether &#8220;full-text eDiscovery&#8221; is required on the server side.<\/li>\n\n\n\n<li>Whether PSTN\/SIP dial-in\/dial-out is required (Teams telephony replacement) &#8211; only indirectly mentioned.<\/li>\n\n\n\n<li>MDM specifications (e.g. app config, certificates, device authorizations) and whether mobile devices may have Internet access.<\/li>\n\n\n\n<li>Required security certifications at vendor level vs. bank&#8217;s own certification of operations (SOC2\/ISO artifacts from vendors are only a building block for self-hosted and do not replace bank controls; therefore only listed as due diligence input in the blog).  <\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>The requirement &#8220;completely without cloud connectivity&#8221; effectively excludes Microsoft Teams because Microsoft Teams is designed as a SaaS\/cloud service and does not provide an on-premises version. This shifts the problem from &#8220;which tool is similar?&#8221; to &#8220;which system can be operated technically, organizationally and regulatory in such a way that no third-party cloud services (incl. push gateways, telemetry\/registration, marketplace access, update dependencies) are necessary in productive operation&#8221;. <\/p>\n","protected":false},"author":15,"featured_media":5591,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-7420","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-nicht-kategorisiert"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Teams alternative without cloud connectivity for on-prem hosting - ONLU AG<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/onlu.ch\/en\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Teams alternative without cloud connectivity for on-prem hosting - ONLU AG\" \/>\n<meta property=\"og:description\" content=\"The requirement &quot;completely without cloud connectivity&quot; effectively excludes Microsoft Teams because Microsoft Teams is designed as a SaaS\/cloud service and does not provide an on-premises version. This shifts the problem from &quot;which tool is similar?&quot; to &quot;which system can be operated technically, organizationally and regulatory in such a way that no third-party cloud services (incl. push gateways, telemetry\/registration, marketplace access, update dependencies) are necessary in productive operation&quot;.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/onlu.ch\/en\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\/\" \/>\n<meta property=\"og:site_name\" content=\"ONLU AG\" \/>\n<meta property=\"article:published_time\" content=\"2026-02-26T10:54:44+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-05-05T13:25:19+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/onlu.ch\/wp-content\/uploads\/2022\/01\/ONLUBanner.png\" \/>\n\t<meta property=\"og:image:width\" content=\"1024\" \/>\n\t<meta property=\"og:image:height\" content=\"683\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"Alen Bisanovic\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Alen Bisanovic\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"16 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/onlu.ch\\\/en\\\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/onlu.ch\\\/en\\\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\\\/\"},\"author\":{\"name\":\"Alen Bisanovic\",\"@id\":\"https:\\\/\\\/onlu.ch\\\/en\\\/#\\\/schema\\\/person\\\/cb9c650ad4476c0d13e99fcb2bfa809d\"},\"headline\":\"Teams alternative without cloud connectivity for on-prem hosting\",\"datePublished\":\"2026-02-26T10:54:44+00:00\",\"dateModified\":\"2026-05-05T13:25:19+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/onlu.ch\\\/en\\\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\\\/\"},\"wordCount\":3228,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/onlu.ch\\\/en\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/onlu.ch\\\/en\\\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/onlu.ch\\\/wp-content\\\/uploads\\\/2022\\\/01\\\/ONLUBanner.png\",\"articleSection\":[\"Nicht kategorisiert\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/onlu.ch\\\/en\\\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/onlu.ch\\\/en\\\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\\\/\",\"url\":\"https:\\\/\\\/onlu.ch\\\/en\\\/teams-alternative-without-cloud-connectivity-for-on-prem-hosting\\\/\",\"name\":\"Teams alternative without cloud connectivity for on-prem hosting - 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