[DOCS] Updating Elastic Security Overview topic (#101922)

* updating overview topic for Kibana

* formatting fixes

* small formatting tweaks

* small formatting tweaks

docs/siem/siem-ui.asciidoc

@@ -1,102 +1,160 @@
 [role="xpack"]
 [[siem-ui]]
-== Using Elastic Security
+== Elastic Security Overview
 
-Elastic Security is a highly interactive workspace designed for security
-analysts. It provides a clear overview of events and alerts from your
-environment, and you can use the interactive UI to drill down into areas of
-interest.
+Elastic Security combines SIEM threat detection features with endpoint
+prevention and response capabilities in one solution. These analytical and
+protection capabilities, leveraged by the speed and extensibility of
+Elasticsearch, enable analysts to defend their organization from threats before
+damage and loss occur.
 
-[float]
-[[hosts-ui]]
-=== Hosts
+Elastic Security provides the following security benefits and capabilities:
 
-The Hosts page provides key metrics regarding host-related security events, and
-data tables and histograms that let you interact with the Timeline Event Viewer.
-You can drill down for deeper insights, and drag and drop items of interest from
-the Hosts page to Timeline for further investigation.
+* A detection engine to identify attacks and system misconfigurations
+* A workspace for event triage and investigations
+* Interactive visualizations to investigate process relationships
+* Inbuilt case management with automated actions
+* Detection of signatureless attacks with prebuilt machine learning anomaly jobs
+and detection rules
 
-[role="screenshot"]
-image::siem/images/hosts-ui.png[]
-
-
-[float]
-[[network-ui]]
-=== Network
-
-The Network page displays key network activity metrics in an interactive map,
-and provides network event tables that enable interaction with Timeline.
-
-[role="screenshot"]
-image::siem/images/network-ui.png[]
-
-[float]
-[[detections-ui]]
-=== Detections (beta)
-
-The Detections feature automatically searches for threats and creates 
-alerts when they are detected. Detection rules define the conditions 
-for when alerts are created. Elastic Security comes with prebuilt rules that
-search for suspicious activity on your network and hosts. Additionally, you can
-create your own rules.
-
-See {security-guide}/detection-engine-overview.html[Detections] for information
-on managing detection rules and alerts.
-
-[role="screenshot"]
-image::siem/images/detections-ui.png[]
-
-[float]
-[[cases-ui]]
-=== Cases (beta)
-
-Cases are used to open and track security issues directly in Elastic Security. 
-Cases list the original reporter and all users who contribute to a case
-(`participants`). Case comments support Markdown syntax, and allow linking to
-saved Timelines. Additionally, you can send cases to external systems from
-within Elastic Security.
+[discrete]
+== Elastic Security components and workflow
 
-For information about opening, updating, and closing cases, see
-{security-guide}/cases-overview.html[Cases] in the Elastic Security Guide.
+The following diagram provides a comprehensive illustration of the Elastic Security workflow.
 
 [role="screenshot"]
-image::siem/images/cases-ui.png[]
-
-[float]
-[[timelines-ui]]
-=== Timeline
-
-Timeline is your workspace for threat hunting and alert investigations. 
-
-[role="screenshot"]
-image::siem/images/timeline-ui.png[Elastic Security Timeline]
-
-You can drag objects of interest into the Timeline Event Viewer to create
-exactly the query filter you need. You can drag items from table widgets within
-Hosts and Network pages, or even from within Timeline itself.
-
-A timeline is responsive and persists as you move through Elastic Security
-collecting data. 
-
-For detailed information about Timeline, see
-{security-guide}/timelines-ui.html[Investigating events in Timeline].
-
-[float]
-[[sample-workflow]]
-=== Sample workflow
-
-An analyst notices a suspicious user ID that warrants further investigation, and
-clicks a URL that links to Elastic Security. 
-
-The analyst uses the tables, histograms, and filtering and search capabilities in
-Elastic Security to get to the bottom of the alert. The analyst can drag items of
-interest to Timeline for further analysis.
-
-Within Timeline, the analyst can investigate further - drilling down,
-searching, and filtering - and add notes and pin items of interest. 
-
-The analyst can name the timeline, write summary notes, and share it with others
-if appropriate.
+image::../siem/images/workflow.png[Elastic Security workflow]
+
+Here's an overview of the flow and its components:
+
+* Data is shipped from your hosts to {es} via beat modules and the Elastic https://www.elastic.co/endpoint-security/[Endpoint Security agent integration]. This integration provides capabilities such as collecting events, detecting and preventing {security-guide}/detection-engine-overview.html#malware-prevention[malicious activity], and artifact delivery. The {fleet-guide}/fleet-overview.html[{fleet}] app is used to
+install and manage agents and integrations on your hosts.
++
+The Endpoint Security integration ships the following data sets:
++
+***  *Windows*: Process, network, file, DNS, registry, DLL and driver loads,
+malware security detections
+*** *Linux/macOS*: Process, network, file
++
+* https://www.elastic.co/integrations?solution=security[Beat modules]: {beats}
+are lightweight data shippers. Beat modules provide a way of collecting and
+parsing specific data sets from common sources, such as cloud and OS events,
+logs, and metrics. Common security-related modules are listed {security-guide}/ingest-data.html#enable-beat-modules[here].
+* The {security-app} in {kib} is used to manage the *Detection engine*,
+*Cases*, and *Timeline*, as well as administer hosts running Endpoint Security:
+** Detection engine: Automatically searches for suspicious host and network
+activity via the following:
+*** {security-guide}/detection-engine-overview.html#detection-engine-overview[Detection rules]: Periodically search the data
+({es} indices) sent from your hosts for suspicious events. When a suspicious
+event is discovered, a detection alert is generated. External systems, such as
+Slack and email, can be used to send notifications when alerts are generated.
+You can create your own rules and make use of our {security-guide}/prebuilt-rules.html[prebuilt ones].
+*** {security-guide}/detections-ui-exceptions.html[Exceptions]: Reduce noise and the number of
+false positives. Exceptions are associated with rules and prevent alerts when
+an exception's conditions are met. *Value lists* contain source event
+values that can be used as part of an exception's conditions. When
+Elastic {endpoint-sec} is installed on your hosts, you can add malware exceptions
+directly to the endpoint from the Security app.
+*** {security-guide}/machine-learning.html#included-jobs[{ml-cap} jobs]: Automatic anomaly detection of host and
+network events. Anomaly scores are provided per host and can be used with
+detection rules.
+** {security-guide}/timelines-ui.html[Timeline]: Workspace for investigating alerts and events.
+Timelines use queries and filters to drill down into events related to
+a specific incident. Timeline templates are attached to rules and use predefined
+queries when alerts are investigated. Timelines can be saved and shared with
+others, as well as attached to Cases.
+** {security-guide}/cases-overview.html[Cases]: An internal system for opening, tracking, and sharing
+security issues directly in the Security app. Cases can be integrated with
+external ticketing systems.
+** {security-guide}/admin-page-ov.html[Administration]: View and manage hosts running {endpoint-sec}.
+
+{security-guide}/ingest-data.html[Ingest data to Elastic Security] and {security-guide}/install-endpoint.html[Configure and install the Elastic Endpoint integration] describe how to ship security-related
+data to {es}.
+
+
+For more background information, see:
+
+* https://www.elastic.co/products/elasticsearch[{es}]: A real-time,
+distributed storage, search, and analytics engine. {es} excels at indexing
+streams of semi-structured data, such as logs or metrics.
+* https://www.elastic.co/products/kibana[{kib}]: An open-source analytics and
+visualization platform designed to work with {es}. You use {kib} to search,
+view, and interact with data stored in {es} indices. You can easily compile
+advanced data analysis and visualize your data in a variety of charts, tables,
+and maps.
+
+[discrete]
+=== Compatibility with cold tier nodes
+
+Cold tier is a {ref}/data-tiers.html[data tier] that holds time series data that is accessed only occasionally. In {stack} version >=7.11.0, {elastic-sec} supports cold tier data for the following {es} indices:
+
+* Index patterns specified in `securitySolution:defaultIndex`
+* Index patterns specified in the definitions of detection rules, except for indicator match rules
+* Index patterns specified in the data sources selector on various {security-app} pages
+
+{elastic-sec} does NOT support cold tier data for the following {es} indices:
+
+* Index patterns controlled by {elastic-sec}, including signals and list indices
+* Index patterns specified in indicator match rules
+
+Using cold tier data for unsupported indices may result in detection rule timeouts and overall performance degradation.
+
+[discrete]
+[[self-protection]]
+==== Elastic Endpoint self-protection
+
+Self-protection means that {elastic-endpoint} has guards against users and attackers that may try to interfere with its functionality. This protection feature is consistently enhanced to prevent attackers who may attempt to use newer, more sophisticated tactics to interfere with the {elastic-endpoint}. Self-protection is enabled by default when {elastic-endpoint} installs on supported platforms, listed below.
+
+Self-protection is enabled on the following 64-bit Windows versions:
+
+* Windows 8.1
+* Windows 10
+* Windows Server 2012 R2
+* Windows Server 2016
+* Windows Server 2019
+
+And on the following macOS versions:
+
+* macOS 10.15 (Catalina)
+* macOS 11 (Big Sur)
+
+NOTE: Other Windows and macOS variants (and all Linux distributions) do not have self-protection.
+
+For {stack} version >= 7.11.0, self-protection defines the following permissions:
+
+* Users -- even Administrator/root -- *cannot* delete {elastic-endpoint} files (located at `c:\Program Files\Elastic\Endpoint` on Windows, and `/Library/Elastic/Endpoint` on macOS).
+* Users *cannot* terminate the {elastic-endpoint} program or service.
+* Administrator/root users *can* read the endpoint's files. On Windows, the easiest way to read Endpoint files is to start an Administrator `cmd.exe` prompt. On macOS, an Administrator can use the `sudo` command.
+* Administrator/root users *can* stop the {elastic-agent}'s service. On Windows, run the `sc stop "Elastic Agent"` command. On macOS, run the `sudo launchctl stop elastic-agent` command.
+
+
+[discrete]
+[[siem-integration]]
+=== Integration with other Elastic products
+
+You can use {elastic-sec} with other Elastic products and features to help you
+identify and investigate suspicious activity:
+
+* https://www.elastic.co/products/stack/machine-learning[{ml-cap}]
+* https://www.elastic.co/products/stack/alerting[Alerting]
+* https://www.elastic.co/products/stack/canvas[Canvas]
+
+[discrete]
+[[data-sources]]
+=== APM transaction data sources
+
+By default, {elastic-sec} monitors {apm-app-ref}/apm-getting-started.html[APM]
+`apm-*-transaction*` indices. To add additional APM indices, update the
+index patterns in the `securitySolution:defaultIndex` setting ({kib} -> Stack Management -> Advanced Settings -> `securitySolution:defaultIndex`).
 
+[discrete]
+[[ecs-compliant-reqs]]
+=== ECS compliance data requirements
 
+The {ecs-ref}[Elastic Common Schema (ECS)] defines a common set of fields to be used for
+storing event data in Elasticsearch. ECS helps users normalize their event data
+to better analyze, visualize, and correlate the data represented in their
+events. {elastic-sec} supports events and indicator index data from any ECS-compliant data source.
 
+IMPORTANT: {elastic-sec} requires {ecs-ref}[ECS-compliant data]. If you use third-party data collectors to ship data to {es}, the data must be mapped to ECS.
+{security-guide}/siem-field-reference.html[Elastic Security ECS field reference] lists ECS fields used in {elastic-sec}.