About User Identity
User identity information can help you to identify the source of policy breaches, attacks, or network vulnerabilities, and trace them to specific users. For example, you could determine:
-
Who owns the host targeted by an intrusion event that has a Vulnerable (level 1: red) impact level.
-
Who initiated an internal attack or portscan.
-
Who is attempting unauthorized access to a specified host.
-
Who is consuming an unreasonable amount of bandwidth.
-
Who has not applied critical operating system updates.
-
Who is using instant messaging software or peer-to-peer file-sharing applications in violation of company policy.
-
Who is associated with each indication of compromise on your network.
Armed with this information, you can use other features of the system to mitigate risk, perform access control, and take action to protect others from disruption. These capabilities also significantly improve audit controls and enhance regulatory compliance.
After you configure user identity sources to gather user data, you can perform user awareness and user control.
For more information about identity sources, see About User Identity Sources.
Identity Terminology
This topic discusses common terminology for user identity and user control.
- User awareness
-
Identifying users on your network using identity sources (such as or TS Agent). User awareness enables you to identify users from both authoritative (such as Active Directory) and non-authoritative (application-based) sources. To use Active Directory as an identity source, you must configure a realm and directory. For more information, see About User Identity Sources.
- User control
-
Configuring an identity policy that you associate with an access control policy. (The identity policy is then referred to as an access control subpolicy.) The identity policy specifies the identity source and, optionally, users and groups belonging to that source.
By associating the identity policy with an access control policy, you determine whether to monitor, trust, block, or allow users or user activity in traffic on your network. For more information, see Access Control Policies.
- Authoritative identity sources
-
A trusted server validated the user login (for example, Active Directory). You can use the data obtained from authoritative logins to perform user awareness and user control. Authoritative user logins are obtained from passive and active authentications:
-
Passive authentications occur when a user authenticates through an external repository. ISE/ISE-PIC, the TS Agent, Microsoft Active Directory, and Microsoft Azure Active Directory are passive authentication user repositories supported by the system.
-
Active authentications occur when a user authenticates through preconfigured managed devices. Captive portal is another name for active authentication. Remote Access VPN is another authentication method supported by the system. Active authentication generally uses the same user repositories as passive authentication (the exceptions being ISE/ISE-PIC, and TS Agent, which are passive only).
-
- Non-authoritative identity sources
-
An unknown or untrusted server validated the user login. Traffic-based detection is the only non-authoritative identity source supported by the system. You can use the data obtained from non-authoritative logins to perform user awareness.
About User Identity Sources
The following table provides a brief overview of the user identity sources supported by the system. Each identity source provides a store of users for user awareness. These users can then be controlled with identity and access control policies.
|
User Identity Source |
Server Requirements |
Login Type |
Authentication Type |
User Control |
For more, see... |
|---|---|---|---|---|---|
|
Captive portal |
OpenLDAP Microsoft Active Directory |
Authoritative |
Active |
Yes |
|
|
ISE/ISE-PIC |
Microsoft Active Directory |
Authoritative |
Passive |
Yes |
|
|
Remote Access VPN |
OpenLDAP or Microsoft Active Directory |
Authoritative |
Active |
Yes |
|
|
RADIUS |
Authoritative |
Active |
No, awareness only |
||
|
TS Agent |
Microsoft Windows Terminal Server |
Authoritative |
Passive |
Yes |
|
|
Traffic-based detection (Configured in the network discovery policy.) |
— |
Non-authoritative |
— |
No, awareness only |
Consider the following when selecting identity sources to deploy:
-
You must use traffic-based detection for non-LDAP user logins.
-
You must use traffic-based detection or captive portal to record failed login or authentication activity. A failed login or authentication attempt does not add a new user to the list of users in the database.
-
The captive portal identity source requires a managed device with a routed interface. You cannot use an inline (also referred to as tap mode) interface with captive portal.
Data from those identity sources is stored in the management center's users database and the user activity database. You can configure management center-server user downloads to automatically and regularly download new user data to your databases.
After you configure identity rules using the desired identity source, you must associate each rule with an access control policy and deploy the policy to managed devices for the policy to have any effect. For more information about access control policies and deployment, see Associating Other Policies with Access Control.
For general information about user identity, see About User Identity.
Best Practices for User Identity
We recommend you review the following information before you set up identity policies.
-
Know user limits
-
Create one realm per AD domain
-
Health monitor
-
Use latest version of ISE/ISE-PIC, two types of remediation
-
User agent support drops in 6.7
-
Captive portal requires routed interface, several individual tasks
Active Directory, LDAP, and realms
The system supports either Active Directory or LDAP for user awareness and control. The association between an Active Directory or LDAP repository and the management center is referred to as a realm. You should create one realm per LDAP server or Active Directory domain. For details about which versions are supported, see Supported Servers for Realms.
The only user identity source supported by LDAP is captive portal. To use other identity sources (with the exception of ISE/ISE-PIC), you must use Active Directory.
For Active Directory only:
-
Create one directory per domain controller.
For details, see Create an LDAP Realm or an Active Directory Realm and Realm Directory
-
Users and groups in trust relationships between two domains are supported provided you add all Active Directory domains and domain controllers as realms and directories, respectively.
For more information, see Realms and Trusted Domains.
Health monitor
The management center health monitor provides valuable information about the status of various management center functions, including:
-
User/realm mismatches
-
Snort memory usage
-
ISE connection status
For more information about health modules, see Health Modules in the Cisco Secure Firewall Management Center Administration Guide.
To set up policies to monitor health modules, see Creating Health Policies in the Cisco Secure Firewall Management Center Administration Guide.
Device-specific user limits
Every physical or virtual management center device has limits to the number of users that can be downloaded. When the user limit is reached, the management center can run out of memory and can function unreliably as a result.
User limits are discussed in User Limits for Microsoft Active Directory.
If you use the ISE/ISE-PIC identity source, you can optionally limit the subnets the management center monitors to reduce memory usage using identity mapping filters as discussed in Create an Identity Policy.
Use the latest version of ISE/ISE-PIC
If you expect to use the ISE/ISE-PIC identity source, we strongly recommend you always use the latest version to make sure you get the latest features and bug fixes.
pxGrid 2.0 (which is used by version 2.6 patch 6 or later; or 2.7 patch 2 or later) also changes the remediation used by ISE/ISE-PIC from Endpoint Protection Service (EPS) to Adaptive Network Control (ANC). If you upgrade ISE/ISE-PIC, you must migrate your mediation policies from EPS to ANC.
More information about using ISE/ISE-PIC can be found in ISE/ISE-PIC Guidelines and Limitations.
To set up the ISE/ISE-PIC identity source, see How to Configure ISE/ISE-PIC for User Control.
Captive portal information
Captive portal is the only user identity source for which you can use either LDAP or Active Directory. In addition, your managed devices must be configured to use a routed interface.
Additional guidelines can be found in Captive Portal Guidelines and Limitations.
Setting up captive portal requires performing several independent tasks. For more information, see How to Configure the Captive Portal for User Control.
TS Agent information
The TS Agent user identity source is required to identify user sessions on a Windows Terminal Server. The TS Agent software must be installed on the Terminal Server machine as discussed in the Cisco Terminal Services (TS) Agent Guide. In addition, you must synchronize the time on your TS Agent server with the time on the management center.
TS Agent data is visible in the Users, User Activity, and Connection Event tables and can be used for user awareness and user control.
For more information, see TS Agent Guidelines.
Associate the identity policy with an access control policy
After you configure your realm, directory, and user identity source, you must set up identity rules in an identity policy. To make the policy effective, you must associate the identity policy with an access control policy.
For more information about creating an identity policy, see Create an Identity Policy.
For more information about creating identity rules, see Create an Identity Rule.
To associate an identity policy with an access control policy, see Associating Other Policies with Access Control.
Identity Deployments
When the system detects user data from a user login, from any identity source, the user from the login is checked against the list of users in the management center user database. If the login user matches an existing user, the data from the login is assigned to the user. Logins that do not match existing users cause a new user to be created, unless the login is in SMTP traffic. Non-matching logins in SMTP traffic are discarded.
The group to which the user belongs is associated with the user as soon as the user is seen by the management center.
The following diagram illustrates how the system collects and stores user data:
Sample identity deployments
The sample deployments discussed in this section are based on the system shown in the following figure.
In the preceding figure, CDO and one managed device are deployed to AWS and the other devices are located on premises. These devices can be either physical or virtual; they just need to be able to communicate with each other.
The two on-premises managed devices are intended to be used as a proxy sequence. You must add those devices to CDO as well.
A proxy sequence is one or more managed devices that can be used to communicate with an LDAP, Active Directory, or ISE/ISE-PIC server. It is necessary only if CDO cannot communicate with your Active Directory or ISE/ISE-PIC server. (For example, CDO might be in a public cloud but Active Directory or ISE/ISE-PIC might be in a private cloud.)
LDAP or Active Directory are needed only for TS Agent and captive portal, as the following paragraphs explain.
For more information about setting up a system like this, see How to Set Up an Identity Policy.
ISE/ISE-PIC identity source
When you deploy the ISE/ISE-PIC identity source, CDO contacts the proxy sequence if CDO cannot contact the ISE/ISE-PIC server directly. Users, groups, and subscriptions are sent from the ISE/ISE-PIC server to the managed device in AWS.
You can optionally have an LDAP server in an ISE/ISE-PIC deployment but because it's optional, it isn't shown in the following figure.
For more information about ISE/ISE-PIC, see The ISE/ISE-PIC Identity Source.
TS Agent identity source
The Terminal Services (TS) Agent software runs on a Microsoft Server and sends CDO user information based on the port range the users log in to the server with. TS Agent gets user identity information from LDAP or Active Directory and sends it to CDO.
For more information about the TS Agent identity source, see The Terminal Services (TS) Agent Identity Source.
Captive portal identity source
Captive portal is the only identity source that supports LDAP in addition to Active Directory. The captive portal identity source is triggered when a user tries to access network resources using the Managed device in AWS, using either an IP address or host name. Captive portal gets user information from LDAP or Active Directory using the proxy sequence and sends user information to CDO.
For more information about the captive portal identity source, see The Captive Portal Identity Source.
Traffic-based detection
Traffic-based detection is designed only to detect applications on the network and therefore has no need for a user repository like Active Directory or for a proxy sequence. For more information about it, see About Detection of Host, Application, and User Data.
How to Set Up an Identity Policy
This topic provides a high-level overview of setting up an identity policy using any available user identity source: TS Agent, ISE/ISE-PIC, captive portal, or Remote Access VPN.
Procedure
| Command or Action | Purpose | |||
|---|---|---|---|---|
|
Step 1 |
(Optional.) Create a realm and directory, one realm for every domain in the forest that contain users you want to use in user control. Also create one directory for every domain controller. Only users and groups that have corresponding management center realms and directories can be used in identity policies.. |
Creating a realm, realm directory is optional if any of the following are true:
The realm is a trusted user and group store, typically a Microsoft Active Directory repository. The management center downloads users and groups at intervals you specify. You can include or exclude users and groups from being downloaded. See Create an LDAP Realm or an Active Directory Realm and Realm Directory. For details about the options to create a realm, see Realm Fields. A directory is an Active Directory domain controller that organizes information about a computer network's users and network shares. An Active Directory controller provides Directory Services for the realm. Active Directory distributes user and group objects across multiple domain controllers, which are peers that propagate local changes between each other by the use of Directory Services. For more information, see the Active Directory technical specification glossary on MSDN. You can specify more than one directory for a realm, in which case each domain controller is queried in the order listed on the realm's Directory tab page to match user and group credentials for user control.
|
||
|
Step 2 |
Synchronize users and groups from the realm. |
To be able to control users and groups, you must synchronize them with the management center. You can synchronize them with users and groups whenever you want or you can configure the system to synchronize them at a specified interval. When you synchronize users and groups, you can specify exceptions; for example, you can exclude the Engineering group from all user control for that realm, or you can exclude the user joe.smith from user controls that apply to the Engineering group. See Synchronize Users and Groups |
||
|
Step 3 |
(Optional.) Create a realm sequence. |
|
||
|
Step 4 |
Create a method to retrieve user and group data (the identity source). |
Set up an identity source with its unique configuration to be able to control users and groups using data stored in the realm. Identity sources include TS Agent, captive portal, or Remote VPN. See one of the following: |
||
|
Step 5 |
Create an identity policy. |
An identity policy contains one or more identity rules, optionally organized in categories. See Create an Identity Policy.
|
||
|
Step 6 |
Create one or more identity rules. |
Identity rules enable you to specify a number of matching criteria, including the type of authentication, network zones, networks or geolocation, realms, realm sequences, and so on. See Create an Identity Rule. |
||
|
Step 7 |
Associate your identity policy with an access control policy. |
An access control policy filters and optionally inspects traffic. An identity policy must be associated with an access control policy to have any effect. See Associating Other Policies with Access Control. |
||
|
Step 8 |
Deploy the access control policy to at least one managed device. |
To use your policy to control user activity, the policy must be deployed to the managed devices to which clients connect. See Deploy Configuration Changes. |
||
|
Step 9 |
Monitor user activity. |
View a list of active sessions collected by user identity sources or a list of user information collected by user identity sources. See Using Workflows in the Cisco Secure Firewall Management Center Administration Guide . An identity policy is not required if all of the following are true:
|
The User Activity Database
The user activity database on the Secure Firewall Management Center contains records of user activity on your network detected or reported by all of your configured identity sources. The system logs events in the following circumstances:
-
When it detects individual logins or logoffs.
-
When it detects a new user.
-
When a system administrator manually delete a user.
-
When the system detects a user that is not in the database, but cannot add the user because you have reached your user limit.
-
When you resolve an indication of compromise associated with a user, or enable or disable indication of compromise rules for a user.
 Note |
If the TS Agent monitors the same users as another passive authentication identity source (such as the ISE/ISE-PIC), the management center prioritizes the TS Agent data. If the TS Agent and another passive source report identical activity from the same IP address, only the TS Agent data is logged to the management center. |
You can view user activity detected by the system using the Secure Firewall Management Center. (.)
The Users Database
The users database on the Secure Firewall Management Center contains a record for each user detected or reported by all of your configured identity sources. You can use data obtained from an authoritative source for user control.
See About User Identity Sources for more information about the supported non-authoritative and authoritative identity sources.
The total number of users the Secure Firewall Management Center can store depends on the Secure Firewall Management Center model, as described in User Limits for Microsoft Active Directory. After the user limit is reached, the system prioritizes previously-undetected user data based on its identity source, as follows:
-
If the new user is from a non-authoritative identity source, the system does not add the user to the database. To allow new users to be added, you must delete users manually or with a database purge.
-
If the new user is from an authoritative identity source, the system deletes the non-authoritative user who has remained inactive for the longest period and adds the new user to the database.
If an identity source is configured to exclude specific user names, user activity data for those user names are not reported to the Secure Firewall Management Center. These excluded user names remain in the database, but are not associated with IP addresses. For more information about the type of data stored by the system, see User Data in the Cisco Secure Firewall Management Center Administration Guide.
If you have management center high availability configured and the primary fails, no logins reported by a captive portal, ISE/ISE-PIC, TS Agent, or Remote Access VPN device can be identified during failover downtime, even if the users were previously seen and downloaded to the management center. The unidentified users are logged as Unknown users on the management center. After the downtime, the Unknown users are reidentified and processed according to the rules in your identity policy.
Note |
If the TS Agent monitors the same users as another passive authentication identity source (ISE/ISE-PIC), the management center prioritizes the TS Agent data. If the TS Agent and another passive source report identical activity from the same IP address, only the TS Agent data is logged to the management center. |
When the system detects a new user session, the user session data remains in the users database until one of the following occurs:
-
A user on the management center manually deletes the user session.
-
An identity source reports the logoff of that user session.
-
A realm ends the user session as specified by the realm's User Session Timeout: Authenticated Users, User Session Timeout: Failed Authentication Users, or User Session Timeout: Guest Users setting.
Feedback