4389 Courses in Cardiff delivered Live Online

Duration 4 Days 24 CPD hours This course is intended for Collaboration Communications Systems Engineers are responsible for planning, deploying, configuring, maintaining, and troubleshooting Microsoft Teams Phone, meetings, and personal and shared space devices, including Microsoft Teams Rooms and Surface Hub. Collaboration Communications Systems Engineers have a fundamental understanding ofÿnetworking, telecommunications, audio/visual and meeting room technologies, identity and access management. They are proficient in managing and monitoring Teams Phone, meetings, and certified devices using the Microsoft Teams admin center, PowerShell, the Microsoft Teams Rooms Pro Portal, and the Call Quality Dashboard. They deploy and configure Microsoft Teams Phone with PSTN connectivity through Microsoft Calling Plans, Operator Connect, Teams Phone Mobile, and Direct Routing. Collaboration Communications Systems Engineers work with Teams Administrators, Microsoft Identity and Access Administrators, and Microsoft 365ÿAdministrators. In addition, they may work with owners of other workloads, including facilitiesÿmanagers, network engineers, security engineers, device manufacturers, telephony providers, and Microsoft Certified solutions providers. This training course is designed to give participants the knowledge and skills to become a Collaboration Communications Systems Engineer. Participants should understand the fundamentals of networking, telecommunications, audio/visual and meeting room technologies, identity and access management, and Microsoft Teams. They will gain hands-on experience configuring and deploying Microsoft Teams Phone, meetings and certified devices including Microsoft Teams Rooms and Surface Hub. The course will also cover how to manage and monitor Teams Phone, meetings, and certified devices using the Microsoft Teams admin center, PowerShell, the Microsoft Teams Rooms Pro Portal, and the Call Quality Dashboard. In addition, the course will cover configuring and deploying Microsoft Teams Phone with PSTN connectivity through Microsoft Calling Plans, Operator Connect, Teams Phone Mobile, and Direct Routing. Prerequisites Microsoft 365 and Microsoft Teams Networking, telecommunications, and audio/visual basics Identity and access management basics 1 - Introduction to Teams meetings and calling Overview of Teams meetings and events Overview of Teams Phone Overview of auto attendants and call queues Overview of Teams devices 2 - Plan for Teams Phone Plan to deploy Teams Phone Plan for Teams Phone PSTN connectivity Determine license requirements Plan for Teams Phone devices Plan and design Teams Phone features Plan for voicemail 3 - Plan for Microsoft Teams Rooms and Surface Hub Determine license requirements for Microsoft Teams Rooms and shared devices Understand differences between Microsoft Teams Rooms on Android and Windows Understand Microsoft Teams Rooms on Surface Hub 2S Understand and plan Teams Room accessories, components, and peripherals Understand Teams Rooms management options 4 - Plan and optimize network performance for Teams media Understand Teams network requirements Design network for media optimization Design and implement QoS 5 - Configure and deploy Teams Phone Configure emergency calling for Teams Calling Plans Manage and configure Microsoft PSTN numbers Configure Operator Connect and Teams Phone Mobile Configure Teams Phone policies Create and manage Teams policies Configure Audio Conferencing 6 - Configure and deploy Teams Phone with Direct Routing Design Direct Routing call flows Implement SIP trunking with Direct Routing Configure Emergency Calling for Direct Routing Extend Teams Direct Routing infrastructure Deploy and maintain a survivable branch appliance 7 - Extend Teams Phone with additional services Understand how Teams interacts with additional services Configure compliance recording in Teams Configure and integrate a certified contact center in Teams Design and deploy voice bots in Teams 8 - Manage meetings and events experiences Explore meetings and events in Microsoft Teams Configure meeting settings Create and manage meeting policies Configure audio conferencing Create and manage meeting templates and template policies Create and manage meetings customization policies Configure live events settings Create and manage live events policies Examine live events across Microsoft 365 9 - Guided project - Create and assign Teams policies to meet business requirements in Microsoft Teams Prepare 10 - Configure and manage voice users Enable users for Teams Phone Enable users for Direct Routing with Teams Phone Enable additional calling features for Teams Phone Enable users for Teams Phone Mobile 11 - Configure auto attendants and call queues Design call flows for auto attendants and call queues Configure auto attendants and call queues Deploy a channel-based call queue Configure resource accounts Configure Microsoft 365 groups for voicemail Interpret call queue conference modes Interpret call queue routing methods Configure holidays for auto attendants and call queues Configure custom music on hold 12 - Configure, deploy, and manage Teams devices Manage Microsoft Teams Phones Manage Microsoft Teams Room Systems Microsoft Teams Rooms management options Manage Surface Hub 2S devices Configure Microsoft Teams SIP gateway Manage Microsoft Teams displays Remote provisioning and sign in for Teams Phones Update Microsoft Teams devices remotely Manage Microsoft Teams device tags 13 - Guided project - Prepare meeting room experiences Prepare 14 - Monitor and troubleshoot Teams collaboration communications systems Diagnose and troubleshoot phone number assignment Diagnose and troubleshoot Teams client issues Diagnose and troubleshoot call failure and call quality issues Report on and troubleshoot Teams calls with Call Quality Dashboard Diagnose and troubleshoot Direct Routing issues Troubleshoot and monitor Teams devices Troubleshoot Teams meetings and calling Troubleshoot Teams Rooms devices

This programme helps communicators to prepare for and deliver an effective speech. Here, you learn to motivate people by speaking to them in terms of the benefits they will receive by taking action. Each instructional segment is followed by participant speeches that put the newly-learned skills into action. We cover public speaking fear and how to move forward despite it, as well as increasing enthusiasm. This builds speaker confidence. By organising information clearly for the audience, participants grow in their conviction and are perceived more as experts. Delegates will be able to: Work through fear of public speaking; Build confidence and enthusiasm by creating meaningful, memorable speeches; Develop greater abilities for thinking and speaking with less preparation; Minimise self-defeating speech and behavior; and Present ideas to, and inspire the audience. Online Format—Introduction to Public Speaking is a 4-hour interactive virtual class. Register for this class and you will be sent ONLINE login instructions prior to the class date. Working with Dr. Atkins of Improving Communications has been a very positive experience. Everything about the program is exemplary! Managers have made it a point to tell me how pleased they are with the improvements made in the communications skills of the participants. The Professional Development Workshop is an extremely effective program. The participants are looking forward to follow-up sessions with Dr. Atkins and we recommend his programs. Heather Ragone, Training ManagerNetwork General

Duration 5 Days 30 CPD hours This course is intended for This course is intended for IT Professionals who are already experienced in general Windows Server, Windows client, Azure, and Microsoft 365 administration, and who want to learn more about using Windows PowerShell for administration. No prior experience with any version of PowerShell or any scripting language is assumed. This course is also suitable for IT Professionals already experienced in server administration, including Microsoft Exchange Server, Microsoft SharePoint Server, and Microsoft SQL Server. This course provides students with the fundamental knowledge and skills to use PowerShell for administering and automating administration of Windows servers. This course provides students the skills to identify and build the command they require to perform a specific task. In addition, students learn how to build scripts to accomplish advanced tasks such as automating repetitive tasks and generating reports. This course provides prerequisite skills supporting a broad range of Microsoft products, including Windows Server, Windows Client, Microsoft Azure, and Microsoft 365. In keeping with that goal, this course will not focus on any one of those products, although Windows Server, which is the common platform for all of those products, will serve as the example for the techniques this course teaches. Prerequisites Before attending this course, students must have: -Experience with Windows networking technologies and implementation. - Experience with Windows Server administration, maintenance, and troubleshooting. 1 - Review Windows PowerShell Learn about Windows PowerShell Get familiar with Windows PowerShell applications Identify factors to install and use Windows PowerShell Configure the Windows PowerShell console Configure the Windows PowerShell Integrated Scripting Environment (ISE) Use Visual Studio Code with PowerShell 2 - Understand the command syntax in Windows PowerShell Discover the structure of PowerShell cmdlets Discover the parameters for using PowerShell cmdlets Review the tab completion feature in PowerShell Display the About files content in PowerShell 3 - Find commands and Get-Help in Windows PowerShell Define modules in PowerShell Find cmdlets in PowerShell Use command aliases in PowerShell Use Show-Command and Get-Help in PowerShell Interpret the help file contents and update the local help content in PowerShell 4 - Manage Active Directory Domain Services using PowerShell cmdlets Manage user accounts in PowerShell Manage groups and group memberships in PowerShell Manage computer accounts in PowerShell Manage organizational units and Active Directory objects in PowerShell 5 - Manage network service settings for Windows devices using PowerShell cmdlets Manage IP addresses in PowerShell Manage IP routing in PowerShell Manage DNS clients in PowerShell Manage Windows Firewall settings in PowerShell 6 - Manage Windows Server settings using PowerShell cmdlets Automate management tasks using the Group Policy management cmdlets Manage server roles and services using PowerShell cmdlets Manage Hyper-V Virtual Machines using PowerShell cmdlets Manage Internet Information Services using PowerShell cmdlets 7 - Manage settings for a local Windows machine using PowerShell cmdlets Manage Windows 10 using PowerShell Manage permissions with PowerShell 8 - Understand the Windows PowerShell pipeline Review Windows PowerShell pipeline and its output Discover object members in PowerShell Control the formatting of pipeline output 9 - Select, sort, and measure objects using the pipeline Sort and group objects by property in the pipeline Measure objects in the pipeline Select a set of objects in the pipeline Select object properties in the pipeline Create and format calculated properties in the pipeline 10 - Filter objects out of the pipeline Learn about the comparison operators in PowerShell Review basic filter syntax in the pipeline Review advanced filter syntax in the pipeline Optimize the filter performance in the pipeline 11 - Enumerate objects in the pipeline Learn about enumerations in the pipeline Review basic syntax to enumerate objects in the pipeline Review advanced syntax to enumerate objects in the pipeline 12 - Send and pass data as output from the pipeline Write pipeline data to a file Convert pipeline objects to other forms of data representation in PowerShell Control additional output options in PowerShell 13 - Pass pipeline objects Pipeline parameter binding Identify ByValue parameters Pass data by using ByValue Pass data by using ByPropertyName Identify ByPropertyName parameters Use manual parameters to override the pipeline Use parenthetical commands Expand property values 14 - Connect with data stores using PowerShell providers Define Windows PowerShell providers Review the built-in providers in PowerShell Access provider help in PowerShell 15 - Use PowerShell drives in PowerShell Explain PowerShell drives in PowerShell Use PowerShell drive cmdlets in PowerShell Manage the file system in PowerShell Manage the registry in PowerShell Work with certificates in PowerShell Work with other PowerShell drives in PowerShell 16 - Review CIM and WMI Review architecture of CIM and WMI Review repositories in CIM and WMI Locate online class documentation by using CIM and WMI cmdlets 17 - Query configuration information by using CIM and WMI List local repository namespaces and classes by using CIM and WMI Query instances by using commands and WMI Query Language Connect to remote computers by using CIM and WMI cmdlets Query repository classes from remote computers by using CIMSession objects 18 - Query and manipulate repository objects by using CIM and WMI methods Discover methods of repository objects by using CIM and WMI Locate class methods and documentation by using CIM and WMI Invoke methods of repository objects by using CIM and WMI 19 - Manage variables in Windows PowerShell scripts Define variables in Windows PowerShell scripts Create variable names in Windows PowerShell scripts Assign values and types to variables in Windows PowerShell scripts Identify the methods and properties of variables in Windows PowerShell scripts Use string variables and methods in Windows PowerShell scripts Use date variables and methods in Windows PowerShell scripts 20 - Work with arrays and hash tables in Windows PowerShell scripts Define an array in Windows PowerShell scripts Work with array lists in Windows PowerShell scripts Define hash tables in Windows PowerShell Scripts Work with hash tables in Windows PowerShell scripts 21 - Create and run scripts by using Windows PowerShell Review Windows PowerShell scripts Modify scripts in the PowerShell Gallery Create scripts using Windows PowerShell Review the PowerShellGet module in Windows PowerShell Run scripts and set the execution policy in Windows PowerShell Review Windows PowerShell and AppLocker Sign the scripts digitally in Windows PowerShell 22 - Work with scripting constructs in Windows PowerShell Review and use the ForEach loop in Windows PowerShell scripts Review and use the If construct in Windows PowerShell scripts Review and use the Switch construct in Windows PowerShell scripts Review the For construct in Windows PowerShell scripts Review other loop constructs in Windows PowerShell scripts Review Break and Continue in Windows PowerShell scripts 23 - Import data in different formats for use in scripts by using Windows PowerShell cmdlets Use the Get-Content command in Windows PowerShell scripts Use the Import-Csv cmdlet in Windows PowerShell scripts Use the Import-Clixml cmdlet in Windows PowerShell scripts Use the ConvertFrom-Json cmdlet in Windows PowerShell scripts 24 - Use methods to accept user inputs in Windows PowerShell scripts Identify values that might change in Windows PowerShell scripts Use the Read-Host cmdlet in Windows PowerShell scripts Use the Get-Credential cmdlet in Windows PowerShell scripts Use the Out-GridView cmdlet in Windows PowerShell scripts Pass parameters to a Windows PowerShell script 25 - Troubleshoot scripts and handle errors in Windows PowerShell Interpret error messages generated for Windows PowerShell commands Add output to Windows PowerShell scripts Use breakpoints in Windows PowerShell scripts Interpret error actions for Windows PowerShell commands 26 - Use functions and modules in Windows PowerShell scripts Review functions in Windows PowerShell scripts Use variable scope in Windows PowerShell scripts Create modules in Windows PowerShell scripts Use the dot sourcing feature in Windows PowerShell 27 - Manage single and multiple computers by using Windows PowerShell remoting Review the remoting feature of Windows PowerShell Compare remoting with remote connectivity Review the remoting security feature of Windows PowerShell Enable remoting by using Windows PowerShell Use one-to-one remoting by using Windows PowerShell Use one-to-many remoting by using Windows PowerShell Compare remoting output with local output 28 - Use advanced Windows PowerShell remoting techniques Review common remoting techniques of Windows PowerShell Send parameters to remote computers in Windows PowerShell Set access protection to variables, aliases, and functions by using the scope modifier Enable multi-hop remoting in Windows PowerShell 29 - Manage persistent connections to remote computers by using Windows PowerShell sessions Review persistent connections in Windows PowerShell Create and manage persistent PSSessions by using Windows PowerShell Disconnect PSSessions by using Windows PowerShell Review the feature of implicit remoting in Windows PowerShell 30 - Review Azure PowerShell module Review Azure PowerShell Review the benefits of the Azure PowerShell module Install the Azure PowerShell module Migrate Azure PowerShell from AzureRM to Azure Review Microsoft Azure Active Directory module for Windows PowerShell and Azure Active Directory PowerShell for Graph modules 31 - Review the features and tools for Azure Cloud Shell Review the characteristics of Azure Cloud Shell Review the features and tools of Azure Cloud Shell Configure and experiment with Azure Cloud Shell 32 - Manage Azure resources with Windows PowerShell Create a new Azure virtual machine by using Windows PowerShell commands Manage Azure virtual machines by using Windows PowerShell commands Manage Azure related storage by using Azure PowerShell Manage Azure subscriptions by using Azure PowerShell 33 - Manage users, groups, and licenses in Microsoft Entra ID by using Windows PowerShell Review benefits to manage Microsoft 365 services by using Windows PowerShell Connect to the Microsoft 365 tenant by using Windows PowerShell Manage users in Microsoft 365 by using Windows PowerShell Manage groups in Microsoft 365 by using Windows PowerShell Manage roles in Microsoft 365 by using Windows PowerShell Manage licenses in Microsoft 365 by using Windows PowerShell 34 - Manage Exchange Online by using Windows PowerShell Connect to Exchange Online by using Windows PowerShell Manage mailboxes in Exchange Online by using Windows PowerShell Manage resources in Exchange Online by using Windows PowerShell Manage admin roles in Exchange Online by using Windows PowerShell 35 - Manage SharePoint Online by using Windows PowerShell Install and connect to SharePoint Online Management Shell by using Windows PowerShell Manage SharePoint Online users and groups by using Windows PowerShell Manage SharePoint sites by using Windows PowerShell Manage SharePoint Online external user sharing by using Windows PowerShell 36 - Manage Microsoft Teams by using Windows PowerShell Review Microsoft Teams PowerShell module Install the Microsoft Teams PowerShell module Manage teams with Microsoft Teams PowerShell module 37 - Create and manage background jobs using Windows PowerShell Define the types of background jobs in Windows PowerShell Start remote jobs and CIM/WMI jobs in Windows PowerShell Monitor jobs in Windows PowerShell Retrieve results for running jobs in Windows PowerShell 38 - Create and manage scheduled jobs using Windows PowerShell Create and run Windows PowerShell scripts as scheduled tasks Define scheduled jobs in Windows PowerShell Create job option and job trigger objects in Windows PowerShell Create and register a scheduled job in Windows PowerShell Retrieve the results from a scheduled job in Windows PowerShell

Telecomms training course description A comprehensive tour of the telecommunications technologies and terminology currently in use, and under development. What will you learn List and describe components of the PSTN. Explain how calls are made over the PSTN Compare analog and digital transmission methods. Describe the technologies within the transport plane. Recognise the benefits of extra features available in today's telephone networks. Telecomms training course details Who will benefit: Anyone new to the Telecommunications industry. Prerequisites: None. Duration 2 days Telecomms training course contents Telephone network architecture Handsets, local loop, distribution points, Local exchanges, main telephone switches, PBXs. Making a call - some basics Telephone call components, how a telephone call works, accessing the local exchange, loop disconnect, DTMF, standards, E.164, PSTN routing, Intelligent Networks, Special Rate Services. Analogue vs Digital Voice characteristics, PSTN bandwidth, analogue signalling, Digital encoding, PCM and the 64k, ADPCM and other voice compression methods. PBXs PABX, Call processing, networking PBXs, PBX facilities, bandwidth, blocking probability and Erlangs, Erlang models, using Erlang tables. Transmission methods Two wire transmission, 64k circuits, Nx64, E1, 2 wire to 4 wire conversion, echo, echo suppression, echo cancellers, twisted pair, coax, fibre optic, power lines, satellite systems, microwave. Signalling Analogue signalling, loop start, earth calling, E&M, AC15. Digital signalling -CAS, robbed bits and E1 slot 16 signalling. Digital signalling CCS, Q.931, SS7, Q.SIG, DPNSS, DASS2. Transport planes PDH, PDH issues, SDH, SDH architecture, SDH standards, SDH bit rates, SDH mulitplexors, DWDM. Networks Circuit Switched Networks, TDM, Packet Switched Networks, Frame Relay, Message Switching, Circuit Switching, STDM, Cell Switching, ATM, ATM cells, ATM traffic parameters, ATM QoS, MPLS. Other network access Modems, modulation, speeds, ISDN, BRI, PRI, xDSL, SDSL, ADSL. Other Services Centrex, VPNs, FeatureNet, CTI, Call Processing Systems, Voice Mail, Automated Attendant Systems, Interactive Voice Response, Call Management Systems, Call Conferencing, Star Services. Mobile communications 3 types of wireless telephone, mobile generations, base stations, cells, GSM, GPRS, 3G, UMTS, WCDMA, 4G, LTE. VoIP overview What is VoIP, VoIP benefits, What is IP? The IP header, Packetising voice, VoIP addressing, H.323, SIP, RTP. Bandwidth requirements.

In this course, students will learn general strategies for planning, designing, developing, implementing, and maintaining an IoT system through various case studies and by assembling and configuring an IoT device to work in a sensor network.

The NCSP® ISO 27001 Specialist accredited (APMG International), certified (NCSC/GCHQ-UK), and recognized (DHS-CISA-USA) certification course teaches Digital Business, Operational Stakeholders, Auditors, and Risk Practitioners a Fast-Track approach to adopting and adapting the ISO 27001 controls in the context of a NIST Cybersecurity Framework program.This course looks at the impact of adapting a principled approach to an enterprise risk management framework to better support cybersecurity decisions within the context of the selected informative reference. It guides participants on the best approach to adapt, implement, and operate (AIO) a comprehensive cybersecurity program that integrates into existing organizational capabilities and incorporates the selected Informative Reference. NCSP® ISO 27001 Specialist introduces the integration of typical enterprise capabilities with cybersecurity from the perspective of the selected cybersecurity informative reference. The overall approach places these activities into systems thinking context by introducing the Service Value Management System composed of three aspects, governance, assurance, and the Z-X Model. With this in place, the course presents the approach to adapt, implement, operate, and improve the organizational cybersecurity posture that builds on the application of the FastTrack™ presented in the NCSP Practitioner. The NIST Cybersecurity Professional (NCSP®) program is the industry's first accredited certification training program that teaches organizations how to build a Digital Value Management Overlay System capable of leveraging the NIST Cybersecurity Framework to deliver the secure, digital business outcomes expected by executives, government regulators, and legal advisors.

Jamf 400, Jamf training course

Jamf Training, Jamf 300 course,

Duration 3 Days 18 CPD hours This course is intended for Senior Consultants (both functional and technical) that aspire to be Solution Architects, or current Solution Architects that are new to the role. The Solution Architect is responsible for the successful design, implementation, deployment and adoption of an overall solution. The Solution Architect ensures that the solution meets the customer?s needs now and in the future. In this course, students will learn about decisions a Solution Architect makes during an implementation, covering security, integrations, Power Apps architecture, Power Automate architecture, and more. This course is designed to give you an introduction to the Solution Architect role. Becoming a Solution Architect/Getting to know your customer Define a Solution Architect Role of a Solution Architect on projects Project Methodology Getting to know your customer Group exercise - Getting to know your customer Conceptualizing the design from requirements How to lead the requirement collection effort Using fit gap analysis Pillars of good architecture Blueprinting the solution architecture Group exercise - Design from requirements Project governance and working as a team Solution Architect's role in project governance Techniques for keeping a project on track Scenarios that could cause a project to fail Group exercise - Project governance and working as a team Power Platform Architecture Key Power Platform architecture components Understand how platform design and limits influence solution architectures Updates and feature releases Understand how to communicate how the platform meets customer needs Data Modeling Data model influences Data model strategy Data types Data relationships Group exercise - Data modeling Analytics and artificial intelligence Planning and evaluating requirements Operational reporting Power BI Enterprise BI Pre-built insights and custom AI Power Apps Architecture Discuss options for apps and how to choose where to start Discuss app composition options Using components as part of your app architecture Considerations for including Portals as an app in your architecture Group exercise - Power Apps Architecture topics Application Lifecycle Management (ALM) Microsoft vision and Solution Architect's role in ALM Environment strategies Defning a solution structure for your deliverable Power Automate Architecture Discuss options for automation and custom logic Review considerations for using triggers and common actions Explore using Business Process Flows (BPF) to guide users through business processes Group Exercise - Evaluate scenarios for Power Automate usage Security Modeling Solution Architect's role in security modeling Discovery and learning your client's environment Controlling access to environments and resources Controlling access to CDS Data Group Exercise - Security Modeling Integration Solution Architects role in Integrations What is an integration and why do we need it Platform features that enable integration CDS Event Publishing Scenarios for group discussion Dynamics 365 Applications Architecture Solution Architect's role when deploying Dynamics 365 apps Architecture Considerations for primary apps Group Exercise - App specific working groups evaluate requirements Power Virtual Agents architecture Introduction Chatbot options Chatbot concepts Best practices Integrate chatbots Power Virtual Agents in Microsoft Teams Robotic Process Automation Introduction Power Automate Desktop Recording and editing tasks Running desktop flows Process advisor Testing and Go Live Solution Architect's role with testing and go live Planning for testing Planning for go live

OpenSSL for engineers training course description A hands on course covering OpenSSL. The course focusses on the use of OpenSSL from the command line as opposed to using its extensive libraries. Certificate authorities are configured along with key generation, HTTPS and a SSL VPN. What will you learn Describe OpenSSL. Use OpenSSL. Describe and implement: Explain how the various technologies involved in an OpenSSL work. OpenSSL for engineers training course details Who will benefit: Network personnel. Prerequisites: IP security foundation for engineers Duration 2 days OpenSSL for engineers training course contents What is OpenSSL? What is SSL? SSL versions, TLS, TLS negotiation, TLS authentication, What is OpenSSL, Command line tool, SSL library. OpenSSH, OpenVPN. Hands on TLS packet analysis. Getting started with OpenSSL Downloading, source code, packages, installing, versions, configuration, openssl command. Cipher suite selection. Hands on Encrypting a file with openssl. Public and private keys Algorithms, creating keys, public keys, private keys, encrypting the private key. Hands on Encrypting a file with keys. Digital signatures Creating signatures, checking validity of signatures, Self signing SSL certificates. Viewing certificates. Certificate files. Converting between formats. Hands on Securing a web server with HTTPS. Simple PKI with OpenSSL Root CA, signing CA, configuration files, Certificate signing requests. Email certificates, TLS server certificates. Hands on Implementing a simple PKI with OpenSSL.