Achilleas Katsaros

Transfer from the IT department to the OTE NT unit due to reorganization, with the current "as-is" job description.

• Lead the design, implementation, and support of IT & ICT solutions, ensuring operational procedures, change management, security management, and network monitoring services are consistently maintained
• Mentor and coach team members, fostering a culture of continuous learning and collaboration
• Perform network cost analysis, budgeting, and end-to-end project management
• Manage RFPs and network procurement processes, ensuring alignment with business needs
• Evaluate IT services delivered to OTE core operations and ICT customers, focusing on quality and continuous improvement
• Build and maintain strong relationships with internal and external stakeholders
• Design and deliver professional ICT solutions with a focus on Network Security and Business Continuity, providing expert advice on complex issues
• Plan, design, and implement IT infrastructure security projects in line with industry best practices and standards
• Actively participate in RFI/RFP processes to ensure optimal technology selection
• Responsible for the network operation of Data Centers in Greece and abroad, including Azure and Google networking services for OTE LZ
• Lead the support and manage the following Network/Security services/infra : Cisco ACI, Cisco Nexus, Cisco DNA, Cisco ISE, Cisco Firepower, Cisco Routers and Switches, Cisco WLC & Access Points, Checkpoint VSX Firewalls, Palo Alto Firewalls, Fortigate NGFW, FortiAnalyzer, F5 BIG-IP LTM Load Balancers, F5 DNS, Proxies Zscaler , SDWAN , Azure and GCP cloud networking services
• Provide Network/Security design solutions for OTE/ICT projects
• Conduct quarterly Networks Capacity Planning and report to upper management

• Managed a high-performing team of Network and Security Infrastructure Specialists
• Directed the IT Network Support team, ensuring the successful execution of all activities with high quality and efficiency
• Oversaw all operational processes, including configuration management, deployments, software upgrades, preventive maintenance, automation, and capacity management
• Managed the support and operation of enterprise-class firewalls, routers, switches, and IDS/IPS systems
• Defined and managed Vendor Service Level Agreements (SLAs) for critical infrastructure and services
• Developed team technical capabilities to adopt and handle new technologies, ensuring high service quality and continuous improvement

• Deployed, configured, and managed Cisco Routers and Switches,
• Deployed, configured, and managed Palo Alto, Checkpoint, and Cisco ASA Firewalls
• Implemented and maintained Load Balancers (ACE, Netscaler), WAF, and IPS solutions
• Troubleshot complex Network and Security issues
• Designed, implemented, and optimized the corporate network infrastructure to ensure performance, security, and scalability
• Created high-level and low-level network designs and implementation plans
• Ensured network infrastructure was up to date, addressing vulnerabilities, and recommending improvements
• Participated in IT projects for the implementation of new information systems in order to ensure the best network communication between them
• Evaluated technical proposals for the supply of network equipment and services in order to ensure that the technical requirements are met and the selection of the optimal solution
• Collaborated with teams of infrastructure, software development and systems operation on application issues in order to optimize the quality of IT services provided
• Designed and implemented Disaster Recovery Plans from a networking perspective
• Collaborated with vendors to resolve complex issues