The main CommuniGate Pro subsystems include:

• Identity Management
• Multi-Domain architecture (field-proven for over 120,000 domains per system), with multihoming and shared-IP configurations.
• Account concept, including Mailbox Storage, File Storage, Account Settings, and Account Information databases.
• Groups, Forwarders, Aliases, and other Domain Objects.
• Meta-Directory with Local and Remote Units.
• LDAP access to Directory and Account databases.
• External Authentication mechanism for integration with 3rd party solutions.
• RADIUS services.
• Billing system with multiple per-Account Balances and reservations.

Storage Management

• Mailbox Storage with multiple Mailboxes, Shared access, ACLs.
• Mailbox formats - text files, file folders, other data containers.
• File Storage with public and private folders, virtual files.
• Groupware Information storage and processing using the iCalendar and vCard standards.

Mail Transfer

• Unified Message Queue processing.
• ESMTP and LMTP mail exchange services.
• Anti-Spam and other protection mechanisms.
• Plugin Interface for high performance virus, spam, and content filtering.
• Automated Mail Processing Rules.
• Mailing List manager with automatic bounce processing and a Web interface to list archives.
• Remote Account Polling using the POP3 protocol.
• External Program Delivery for custom applications.
• Automated Invitation processing for shared resource scheduling.

Real-Time Signaling

• Unified Signal processing.
• XIMSS protocol for Instant Messaging, Presence, audio and video communications.
• SIP protocol for Instant Messaging, Presence, audio and video communications, desktop sharing and real-time collaboration.
• XMPP protocol for Instant Messaging and Presence.
• SMPP protocol for Instant Messaging via SMS.
• NAT Traversal mechanisms (near-end and far-end) for XIMSS, SIP, RTP, and TCP-based media protocols.
• Registrar, forking Proxy, and Presence server functionality.
• Automated Signal Processing Rules.
• Event packages for presence, message-waiting, registration, dialogs, and other services.
• STUN server for client-side NAT Traversal solutions.
• Parlay X Interface.

Real-Time Application Environment

• Domain-specific application environments.
• Media Server component for call termination and conferencing with the built-in NAT traversal and encryption support.
• CG/PL language for quick and robust application design.
• Built-in operations for call control, bridging, and multi-party conferencing.
• Integrated Access to Message and File stores.

Data Access Services

• Multi-protocol, multi-client simultaneous access to all Account data.
• POP3 and IMAP4 mail client access.
• MAPI interface for Microsoft® Windows clients (Outlook and other MAPI-enabled applications).
• WebUser Interface to Mailbox, Groupware and File Stores, to Settings and Information databases, to the Signaling and Message Transfer facilities.
• Multi-lingual Skins for customizable HTML, WAP/WML, and I-Mode Interfaces.
• XIMSS interface providing access to Mailbox, Groupware and File Stores, to Settings and Information databases, to the Signaling and Message Transfer facilities.
• HTTP, WebDAV, FTP, and TFTP access to Account File Stores.
• AirSync interface to E-mail and Groupware data for Microsoft® Windows Mobile clients (server-based ActiveSync).
• CalDAV interface to Calendar and Tasks Mailboxes.
• Publish/Subscribe (WebCal/iCal) HTTP-based operations with Calendar and Tasks mailboxes.
• CardDAV interface to Contacts Mailboxes.
• ACAP access to the Account Information database.

Advanced Security

• SASL Secure Authentication methods.
• GSSAPI (including Kerberos V5) authentication, SSO (single sign-on), and security.
• Client Certificate-based Secure Authentication methods.
• Secure Mail (S/MIME) WebMail implementation (encryption/decryption, digital signing, signature verification).
• Automatic Encryption implementing secure information storage.
• SSL/TLS Secure Transfer for SMTP, SIP, IMAP, POP, HTTP, LDAP, ACAP, PWD and Administration sessions.
• Lawful Interception functionality.

Multi-tier Administration

• WebAdmin interface for administration, provisioning, and monitoring.
• CLI/API interface for administration, provisioning, and monitoring.
• SNMP Agent for remote monitoring.
• Triggers for proactive monitoring.
• Poppwd protocol for remote password modification.
• LDAP-based Provisioning (optional) for integration with legacy systems.
• BSD syslog Server to consolidate log records from third-party components.

Multi-Server Operation

• Distributed Domains for Distributed multiple single-Server configurations.
• Static Clusters for Multi-Server Account partitioning.
• Dynamic Clusters for advanced scalability without Account partitioning. Carrier-grade 99.999%-uptime, field-proven for more than 5,000,000 real active Accounts.
• Cluster of Clusters for extra-large sites (over 10,000,000 active Accounts).