Avaya CMS External Call History Complete Implementation and Configuration Guide 2025

Avaya External Call History (ECH) stands as the pinnacle of contact center analytics, providing unprecedented visibility into customer interactions and operational performance. This comprehensive guide delivers expert insights into ECH implementation, configuration, and optimization strategies that transform contact center operations.

External Call History represents far more than traditional reporting—it's a strategic asset that enables organizations to capture every detail of customer interactions, analyze complex call patterns, and drive data-driven decision making. Unlike standard CMS reporting with its inherent limitations, Avaya External Call History provides granular, real-time data that serves as the foundation for advanced analytics and operational excellence.

Contact center managers and technical professionals implementing ECH gain access to detailed call-by-call analysis, comprehensive customer journey tracking, and sophisticated performance metrics that were previously impossible to achieve. This guide provides the technical depth and practical insights needed to maximize your ECH investment and achieve superior contact center performance.

What is Avaya External Call History?

Avaya External Call History (ECH), also known as External Call History Interface (ECHI), is an optional but transformative feature of the Avaya Call Management System that enables organizations to transfer comprehensive call record data from CMS to external systems for advanced storage, processing, and analysis. This powerful capability transcends the limitations of traditional CMS reporting by capturing every detail of every customer interaction in granular, unsummarized format.

Understanding External Call History Interface (ECHI)

The External Call History Interface represents a paradigm shift in contact center analytics. While standard CMS reporting provides summarized data with inherent storage and retention limitations, ECH captures raw, detailed information for every call segment, preserving complete interaction histories indefinitely based on external storage capacity.

This comprehensive data capture enables what contact center professionals often describe as the "holy grail" of reporting—complete visibility into customer journeys from initial contact through final resolution, regardless of call complexity involving transfers, conferences, or extended hold periods. The granular nature of ECH data supports sophisticated analytical applications that would be impossible with traditional reporting approaches.

Core Functionality and Technical Architecture

Avaya ECH operates by intercepting call processing events within the CMS environment and formatting them into structured data records that are transmitted to external systems using secure protocols such as SFTP. This real-time data capture begins the moment a call enters the CMS environment and continues throughout the entire customer interaction lifecycle.

The technical foundation of ECH centers around the concept of call segments, where each segment represents a distinct phase of customer interaction. Simple calls generate single segments, while complex interactions involving transfers, conferences, or routing through multiple skills create multiple segments linked by a common Call ID (CALLID). This architecture enables complete "cradle-to-grave" analysis of customer experiences regardless of interaction complexity.

ECH vs. Standard CMS Reporting: Critical Differences

Understanding the fundamental differences between External Call History data and standard CMS reporting is essential for appreciating the transformative value of ECH implementation. Standard CMS reporting operates within database constraints that limit data retention, granularity, and accessibility. CMS typically summarizes data over time and may archive or purge older records to maintain system performances.

In contrast, External Call History captures unsummarized, granular data for every call interaction, preserving complete details indefinitely subject only to external storage capacity. This approach enables historical trend analysis spanning years, detailed forensic investigation of specific customer interactions, and application of advanced analytics techniques requiring access to individual call records.

The data richness available through ECH data set substantially exceeds standard reporting capabilities. While CMS reports might indicate that an agent handled 50 calls with an average talk time of 3 minutes, ECH data reveals the complete story of each individual interaction, including timing details for every call phase, comprehensive routing information, and complete audit trails of customer journeys through contact center infrastructure.

Business Impact and Strategic Value

Organizations implementing Avaya ECH Interface typically discover analytical capabilities that extend far beyond their initial expectations. The granular nature of ECH data enables sophisticated analysis of customer behavior patterns, identification of operational inefficiencies invisible through traditional reporting, and development of predictive models for workforce planning and customer experience optimization.

The strategic value of External Call History becomes apparent when organizations apply modern analytics techniques to the comprehensive data sets. Machine learning algorithms can identify patterns in customer behavior, predict call volumes with greater accuracy, and automatically detect service quality issues before they impact customer satisfaction. These capabilities represent a significant competitive advantage in today's customer-centric business environment.

Technical Architecture and Components

The technical architecture of ECH interface comprises several interconnected components that work together to capture, process, and transmit call data from the CMS environment to external analytical systems. Understanding this architecture is crucial for successful implementation and ongoing optimization of ECH capabilities.

Core System Components and Data Flow

The ECH architecture centers around the CMS server, which serves as both the data source and initial processing point for call history information. Within the CMS environment, the External Call History package operates as an integrated module that interfaces directly with the call processing engine to capture real-time call events without impacting system performance.

The primary components include the data capture engine, which monitors call processing events and creates structured records of the call; the data formatting module, which converts raw call events into standardized ECH record formats; the transmission engine, which handles secure transfer of the records to external systems and the configuration management system, which controls ECH behavior and external system connectivity parameters.

The data processing pipeline begins when CMS receives the first call processing message, triggering ECH to create a new call record identified by a unique Call ID. As calls progress through various states—queuing, routing, answering, holding, transferring, or conferencing—ECH continuously updates call details with timing information, routing decisions, agent assignments, and other relevant metadata.

Network Architecture and Security Considerations

ECH implementations require careful network architecture design to ensure reliable data transmission while maintaining security and performance standards. The system typically operates using a push model, where the CMS server initiates connections to external systems to transmit call data using secure protocols.

Network connectivity between CMS and external systems must accommodate both routine data transmission and potential failure scenarios. ECH includes configurable buffering capabilities that store the records locally when external systems are temporarily unavailable. Buffer sizes are configurable per ACD and can accommodate thousands of calls, ensuring minimal data loss during extended outages.

Security considerations are paramount in ECH network design. The system supports SSH-based secure file transfer protocols (SFTP) to protect call data during transmission. Public key authentication eliminates password-based vulnerabilities, while proper firewall configurations and access controls limit ECH connectivity to authorized systems only.

High Availability and Redundancy

For mission-critical contact center operations, External Call History Interface high availability configurations reduce the potential for data loss during system failures or maintenance activities. In high availability environments, ECH can operate on either the primary or secondary CMS server, but not both simultaneously, preventing data duplication while ensuring continuous call history capture.

The high availability architecture includes considerations for external system redundancy. Organizations may implement multiple external systems receiving ECH data, providing backup capabilities and load distribution. However, this approach requires careful coordination to prevent data inconsistencies and ensure all systems receive complete, accurate copy of the call data.

Installation and Configuration Guide

Implementing External Call History Interface requires systematic planning and execution to ensure successful deployment and optimal performance. This comprehensive installation guide provides step-by-step instructions developed through extensive field experience with ECH implementations.

Pre-Installation Planning and Prerequisites

Before beginning ECH installation, organizations must complete critical planning activities and verify all prerequisites are met. The planning phase prevents common implementation pitfalls and ensures the ECH system meets organizational requirements from deployment day one.

The first prerequisite is verification that the CMS system is authorized for the ECH package. External Call History is an optional feature requiring specific licensing from Avaya. Organizations should verify authorization status using the `auth_display` command within the CMS administration interface. If ECH is not authorized, contact your Avaya representative to obtain necessary licensing before proceeding.

Infrastructure planning is equally critical. ECH requires a separate computer system for storage and processing of call records, as the CMS system cannot serve as the destination for ECH data. This external system must have adequate storage capacity, processing power, and network connectivity to handle expected data volumes while maintaining appropriate security measures including user authentication, access controls, and data encryption capabilities.

Step-by-Step Installation Process

The ECH installation process involves several distinct phases that must be completed successfully before proceeding to subsequent steps. Installation should be performed during maintenance windows when CMS can be safely taken offline, as the process requires CMS to be stopped.

Phase 1: System Preparation and Verification

Begin installation by ensuring the CMS software is stopped and the IDS (Integrated Data Server) software is running. This configuration is required for ECH installation to access necessary system components. Verify system state using the `cmssvc` command and select appropriate options to stop CMS if currently running.

Access the CMS administration interface using `cmssvc` and select the `auth_display` option to verify current system authorizations. The system displays all authorized features, and ECH should appear if proper licensing is in place. If ECH is not listed, resolve licensing issues before proceeding.

Phase 2: Package Installation and Configuration

Initiate ECH package installation by entering the `cmsadm` command and selecting the `pkg_install` option. The system displays a menu of available packages for installation. Select the External Call History option (typically option 2) to begin the installation process.

The installation process prompts for several configuration parameters defining ECH operation. The first prompt requests the full path of the program to transmit external call history files. Accept the default value `/cms/dc/chr/no_op.sh` unless custom transmission scripts have been developed. The second prompt requests the full path of the program to check external call history file transmission, again accepting the default value unless custom checking scripts are required.

Phase 3: Buffer Configuration and Initial State

The installation process prompts for buffer configuration for each administered ACD. Buffer size determines how many records are held locally if external systems cannot accept data. Buffer sizes range from 0 to 99,999 records per ACD. For high-volume contact centers, buffer sizes of 10,000 to 50,000 records per ACD provide adequate protection against temporary external system outages while avoiding excessive memory consumption.

The final installation prompt asks whether ECH should start in the on or off state. The default is off, which is recommended for initial installations. Starting ECH in the off state allows administrators to complete external system configuration and testing before beginning actual data transmission.

Post-Installation Configuration and Testing

Before beginning ECH installation, organizations must complete critical planning activities and verify all prerequisites are met. The planning phase prevents common implementation pitfalls and ensures the ECH system meets organizational requirements from deployment day one.

SSH Key Generation and Management

Avaya ECH Interface uses SSH-based authentication for secure data transmission. Generate an SSH key pair on the CMS server using `ssh-keygen -t rsa -f /cms/dc/chr/echi.key`. This creates both private and public keys in the specified directory.

The public key must be installed on external systems to enable authentication. Display public key content using `cat /cms/dc/chr/echi.key.pub` and copy the complete key string, including the "ssh-rsa" prefix. Add this public key to the authorized_keys file on external systems for the user account receiving ECH data.

Network Configuration and Connectivity Testing

Configure network connectivity by adding external system hostnames to the CMS hosts file. Edit `/etc/hosts` and add entries mapping external system IP addresses to hostnames used in ECH configuration. Test SSH connectivity from CMS server to external systems using `ssh -l username -i /cms/dc/chr/echi.key external-server.company.com`. This test should complete successfully without password prompts, confirming SSH key authentication is working properly.

Data Schema and Field Definitions

The ECHI data schema represents one of the most comprehensive call tracking systems available in the contact center industry. Understanding the complete data schema is essential for maximizing analytical value and developing effective reporting solutions.

Core Data Structure and Call Relationships

ECH data is organized around the call legs, where each segment represents a distinct phase of customer interaction with the contact center. Simple calls answered by agents and completed without transfer generate single segments. However, calls involving transfers, conferences, or other routing complexity generate multiple segments, all linked by a common Call ID (CALLID).

The relationship between different segments enables complete "cradle-to-grave" analysis of customer interactions regardless of complexity. When calls are transferred from one agent to another, ECH creates new segments for second agent interactions while maintaining connections to original segments through shared CALLIDs. This approach enables comprehensive customer journey analysis and contact center performance evaluation.

Temporal Data Fields and Timing Analysis

ECH captures extensive timing information enabling precise analysis of call flow and performance metrics. Temporal data fields provide granular insight into every phase of customer experience, from initial contact through final disposition.

Call Segment Timing

Fundamental timing fields include `segstart` and `segstop`, marking the beginning and end of each call segment. These timestamps are recorded in Unix epoch format (seconds since January 1, 1970) and are available in both local time and UTC variants to support global contact center operations.

The `duration` field captures total trunk holding time from call segment beginning until caller disconnection. This metric is crucial for understanding resource utilization and identifying efficiency improvement opportunities. For transferred calls, original trunks remain associated with all the segments until call completion, providing complete visibility into resource consumption.

Agent Activity and Performance Timing

ECH provides detailed timing information for agent activities, including `talktime`, measuring total talk time for answering agents in each segment. This field excludes hold time and other non-talk activities, providing accurate measures of actual agent-customer interaction time.

The `acwtime` field captures After Call Work time associated with each call segment. ACW time is critical for workforce planning and productivity analysis, representing time agents spend completing call-related tasks after customer disconnection. Understanding ACW patterns helps contact centers optimize agent schedules and identify training opportunities.

Agent and Resource Identification

ECH captures comprehensive information about agents, resources, and locations involved in each call segment. This information is essential for performance analysis, workforce management, and operational optimization.

Agent Identification and Performance Tracking

The `origlogid` field contains login IDs of agents originating calls, typically used for outbound calls or internal transfers. The `anslogid` field identifies agents answering calls in each segment. For calls involving supervisor observation or assistance, the `lastobserver` field captures login IDs of last agents who service-observed or bridged onto calls.

These agent identification fields enable detailed analysis of agent performance, including call handling patterns, transfer rates, and collaboration activities. Data can identify high-performing agents, training needs, and process improvement opportunities.

Call Routing and VDN Information

Modern contact centers rely on sophisticated call routing logic implemented through VDNs and vectors. ECH captures comprehensive information about call routing decisions and paths calls take through contact center infrastructure.

VDN and Vector Tracking

The `firstvdn` field identifies first VDNs associated with each call segment, while `dispvdn` captures VDNs associated with calls at disposition. This information enables analysis of call routing effectiveness and identification of routing patterns impacting customer experience.

Vector information is captured through `firstvector` and `dispivector` fields, identifying vectors associated with VDNs at different points in call lifecycles. Vector analysis reveals routing optimization opportunities and helps identify vectors causing delays or inefficiencies.

Advanced Use Cases and Applications

The comprehensive nature of Avaya ECH data enables advanced analytical applications that extend far beyond traditional contact center reporting. Organizations implementing ECH often discover transformative insights and capabilities that revolutionize their approach to customer experience management and operational optimization.

Customer Journey Analytics and Experience Optimization

One of the most powerful applications of ECH data is comprehensive customer journey analysis tracking individual customer interactions across multiple touchpoints and time periods. Unlike traditional reporting focusing on individual calls or agent performance, customer journey analytics uses ECH data to understand complete customer experiences and identify improvement opportunities.

Multi-Touch Customer Analysis

Avaya ECH enables organizations to track individual customers across multiple interactions by analyzing calling party information and call patterns. This capability reveals important insights about customer behavior, including repeat call patterns, escalation tendencies, and resolution effectiveness. Organizations can identify customers requiring multiple contacts to resolve issues and analyze root causes of these inefficiencies.

The granular timing information in ECH data enables precise analysis of customer patience and behavior patterns. By analyzing queue times, hold times, and abandonment patterns, organizations identify optimal balances between service levels and resource allocation. This analysis often reveals that small improvements in response times have disproportionate impacts on customer satisfaction and operational efficiency.

Artificial Intelligence and Machine Learning Applications

The rich, granular nature of ECH data makes it an ideal foundation for artificial intelligence and machine learning applications providing predictive insights and automated optimization capabilities.

Predictive Analytics for Workforce Management

ECH data provides historical foundations needed for sophisticated workforce management applications that predict call volumes, handle times, and staffing requirements with greater accuracy than traditional forecasting methods. Machine learning algorithms analyze historical ECH data to identify patterns and trends that human analysts might miss.

These predictive capabilities enable more accurate staffing decisions, better schedule optimization, and improved service level management. Organizations use ECH-based predictive models to anticipate busy periods, identify seasonal patterns, and optimize agent schedules to meet service level objectives while minimizing costs.

Conversational AI Integration

Organizations implementing conversational AI and chatbot technologies can use ECH data to understand how customers interact with automated systems and identify improvement opportunities. ECH data reveals patterns in customer behavior that inform AI training and optimization efforts.

Integration of ECH data with conversational AI platforms enables organizations to develop sophisticated routing algorithms considering customer history, interaction patterns, and predicted needs. This capability significantly improves first-call resolution rates and customer satisfaction.

Advanced Performance Analytics

ECH data enables sophisticated performance analysis that goes beyond traditional metrics to provide deeper insights into agent effectiveness, operational efficiency, and customer satisfaction drivers.

Agent Performance Optimization

Traditional agent performance metrics focus on basic measures such as call volume, handle time, and availability. Avaya ECH enables much more sophisticated analysis considering call complexity, customer satisfaction outcomes, and collaborative activities such as transfers and conferences.

ECH-based performance analysis identifies agents excelling at handling complex calls, those most effective at first-call resolution, and those demonstrating strong collaboration skills. This granular performance insight enables more targeted coaching and development efforts and helps organizations optimize agent assignments based on individual strengths and capabilities.

Security Considerations and Best Practices

Security is paramount in ECH implementations, as the system handles sensitive customer interaction data that may include personally identifiable information (PII), payment card data, and other confidential information. A comprehensive security strategy must address data protection throughout the entire ECH lifecycle.

Data Classification and Protection

The first step in developing an ECH security strategy is understanding the types of data being captured and their respective sensitivity levels. ECH data set typically includes customer phone numbers, agent identifications, call timing information, and potentially sensitive metadata about customer interactions.

Personal Information Protection

Customer phone numbers captured in ECH data constitute personally identifiable information requiring protection according to applicable privacy regulations such as GDPR, CCPA, and industry-specific requirements. Organizations must implement appropriate controls ensuring this information is accessed only by authorized personnel and used only for legitimate business purposes.

The `callingparty` and `dialednumber` fields in ECH data require particular attention, as they directly identify customers and their communication patterns. Organizations should consider implementing data masking or tokenization techniques for these fields when data is used for analytical purposes that don't require actual phone numbers.

Network Security and Data Transmission

ECH data transmission between CMS servers and external systems represents a critical security control point requiring robust protection mechanisms to prevent data interception or unauthorized access.

Encryption in Transit

All Avaya ECH data transmissions should use strong encryption protocols to protect data during network transmission. The recommended approach is SSH File Transfer Protocol (SFTP) with strong encryption algorithms and key lengths. Organizations should avoid unencrypted FTP or other protocols transmitting data in clear text.

SSH configuration should be hardened according to industry best practices, including disabling weak encryption algorithms, implementing strong key exchange mechanisms, and using appropriate cipher suites. Regular security assessments should verify SSH configurations remain secure and current with security standards.

Authentication and Access Management

Robust authentication and access management controls are essential for protecting ECH data and ensuring only authorized personnel can access sensitive information.

SSH Key Management

ECH implementations typically use SSH public key authentication for secure data transmission. Proper SSH key management is crucial for maintaining security and preventing unauthorized access. SSH keys should be generated using strong algorithms (RSA 2048-bit minimum, preferably RSA 4096-bit or ECDSA) and protected with appropriate file permissions.

SSH private keys should be stored securely on CMS servers with restricted file permissions (600 or 400) and accessible only to ECH service accounts. Public keys should be properly installed on external systems and associated with dedicated service accounts having minimal privileges necessary for ECH data reception.

Troubleshooting Common Issues

ECH implementations, while generally reliable, can encounter various technical challenges requiring systematic troubleshooting approaches. Understanding common issues and their resolution methods is essential for maintaining consistent ECH operation and ensuring data integrity.

Data Transmission Failures

Data transmission failures represent one of the most common categories of ECH issues, often manifesting as missing data files, incomplete transmissions, or connection errors between CMS and external systems.

SSH Connectivity Problems

SSH connectivity issues are frequently encountered during initial ECH setup and can occur during ongoing operations due to network changes, security updates, or system maintenance activities. The first step in diagnosing SSH connectivity problems is testing connections manually from CMS servers to external systems.

Use the command `ssh -l username -i /cms/dc/chr/echi.key external-server.company.com` to test SSH connectivity. If this command fails, issues may be related to network connectivity, SSH key authentication, or external system configuration. Check network connectivity using ping and telnet commands to verify external systems are reachable and SSH ports are accessible.

Performance and Capacity Issues

Performance issues can affect both ECH data generation and transmission, potentially leading to data loss or system instability.

CMS Performance Impact

While Avaya CMS External Call History is designed to operate with minimal impact on CMS performance, high-volume environments or improperly configured systems may experience performance degradation. Monitor CMS system resources during ECH operation to identify potential performance issues.

Key performance indicators to monitor include CPU utilization, memory usage, disk I/O, and network utilization. If ECH operation causes performance problems, consider adjusting ECH configuration parameters such as transmission frequency or buffer sizes to reduce system load.

Performance Optimization

Optimizing ECH performance is crucial for maintaining system stability while maximizing the value of captured data. Performance optimization involves balancing data completeness with system resource utilization and ensuring ECH operation doesn't adversely impact contact center operations.

System Resource Optimization

ECH performance optimization begins with proper system resource allocation and configuration. The CMS server must have adequate CPU, memory, and storage resources to handle ECH processing in addition to normal call management activities.

Monitor system resource utilization during peak call periods to identify potential bottlenecks. CPU utilization should remain below 80% during normal operations, with adequate headroom for peak periods. Memory utilization should be monitored to ensure ECH buffering doesn't cause memory pressure affecting call processing performance.

ROI and Business Benefits

The return on investment (ROI) for Avaya ECH implementations can be substantial when organizations effectively leverage comprehensive data capabilities for operational optimization and strategic decision-making.

Operational Efficiency Improvements

ECH data enables organizations to identify and eliminate operational inefficiencies that may not be apparent through traditional reporting methods. The granular visibility provided by ECH reveals opportunities for process optimization, resource reallocation, and performance improvement.

Typical efficiency improvements include reduced average handle times through better agent training and coaching, improved first-call resolution rates through enhanced routing and knowledge management, and optimized staffing levels through more accurate forecasting and scheduling.

Customer Experience Enhancement

The detailed customer journey insights provided by ECH data enable organizations to identify and address customer experience issues impacting satisfaction and loyalty. Organizations can use ECH data to understand customer behavior patterns, identify pain points in customer journeys, and optimize service delivery accordingly.

Customer experience improvements often result in increased customer satisfaction scores, reduced customer churn, and improved customer lifetime value. These benefits can significantly exceed the cost of ECH implementation and ongoing operation.

Conclusion

Avaya CMS External Call History Interface represents a transformative tool for organizations seeking to maximize the value of their contact center data investments. The comprehensive, granular data provided by ECH enables sophisticated analytical applications that can revolutionize contact center operations and customer experience management.

Successful ECH implementation requires careful planning, thorough understanding of technical requirements, and ongoing attention to security, performance, and data quality considerations. Organizations that invest in proper ECH implementation and leverage the data effectively can achieve significant returns through operational efficiency improvements, enhanced customer experience, and better strategic decision-making.

The future of contact center analytics will likely see continued evolution in analytical technologies, integration capabilities, and regulatory requirements. Organizations implementing Avaya ECH Interface today should design solutions with flexibility and scalability in mind to accommodate future developments and changing business requirements.

As contact centers continue to play increasingly important roles in customer experience and business success, the detailed insights provided by ECH will become even more valuable for organizations seeking to maintain competitive advantage and operational excellence.