App_Control

Application Control

This chapter describes how to configure and manage the Application Control feature in SonicOS. This chapter contains the following sections:

 
Application Control Overview
 
Licensing Application Control
 
App Rules
 
App Control Advanced
 
Match Objects
 
Action Objects
 
Address Objects
 
Service Objects
 
Email Address Objects
 
Verifying App Control Configuration
 
App Control Use Cases
 
Glossary

Application Control Overview

This section provides an introduction to the SonicOS Application Control feature. This section contains the following subsections:

 
What is Application Control?
 
Benefits of Application Control
 
How Does Application Control Work?

What is Application Control?

Application Control provides a solution for setting policy rules for application signatures. Application Control policies include global App Control policies, and App Rules policies that are more targeted. As a set of application-specific policies, Application Control gives you granular control over network traffic on the level of users, email addresses, schedules, and IP-subnets. The primary functionality of this application-layer access control feature is to regulate Web browsing, file transfer, email, and email attachments.

In SonicOS 5.8, the ability to control application layer traffic in SonicOS is significantly enhanced with the ability to view real-time application traffic flows, and new ways to access the application signature database and to create application layer rules. SonicOS 5.8 integrates application control with standard network control features for more powerful control over all network traffic.

About App Control Policies

SonicOS 5.8 introduces a new user interface for application control with the Firewall > App Control Advanced page. This screen provides a simple and direct way of configuring global application control rules, known as App Control policies. You can quickly enable blocking or logging for a whole category of applications, and can easily locate and do the same for an individual application or individual signature. Once enabled, the category, application, or signature is blocked or logged globally without the need to create an App Rules policy on the Firewall > App Rules page.

In SonicOS 5.8, all application detection and prevention configuration is available on the Firewall > App Control Advanced page.

About App Rules Policies

App Rules policies are more targeted because they combine a match object, action object, and possibly email address object into a policy. For flexibility, App Rules policies can access the same application controls for any of the categories, applications, or signatures available on the App Control Advanced page, giving you two methods of controlling applications in your network. The Firewall > Match Objects page provides a way to create Application List objects, Application Category List objects, and Application Signature List objects for use as match objects in an App Rules policy.

About Application Control Capabilities

Application Control’s data leakage prevention component provides the ability to scan files and documents for content and keywords. Using Application Control, you can restrict transfer of certain file names, file types, email attachments, attachment types, email with certain subjects, and email or attachments with certain keywords or byte patterns. You can deny internal or external network access based on various criteria.

Based on SonicWALL’s Reassembly Free Deep Packet Inspection technology, Application Control also features intelligent prevention functionality which allows you to create custom, policy-based actions. Examples of custom actions include the following:

 
Blocking entire applications based on their signatures
 
Blocking application features or sub-components
 
Bandwidth throttling for file types when using the HTTP or FTP protocols
 
Blocking an attachment
 
Sending a custom block page
 
Sending a custom email reply
 
Redirecting an HTTP request
 
Sending a custom FTP reply over an FTP control channel

While Application Control primarily provides application level access control, application layer bandwidth management and data leakage prevention, it also includes the ability to create custom application or protocol match signatures. You can create a custom App Rules policy that matches any protocol you wish, by matching a unique piece of the protocol. See “Custom Signature” .

Application Control provides excellent functionality for preventing the accidental transfer of proprietary documents. For example, when using the automatic address completion feature of Outlook Exchange, it is a common occurrence for a popular name to complete to the wrong address. See the following figure for an example.

Benefits of Application Control

The Application Control functionality provides the following benefits:

 
Application based configuration makes it easier to configure policies for application control.
 
The Application Control subscription service provides updated signatures as new attacks emerge.
 
The related Application Intelligence functionality, as seen in App Flow Monitor and the Real Time Visualization Monitor, is available upon registration as a 30-day free trial App Visualization license. This allows any registered SonicWALL appliance to clearly display information about application traffic in the network. The App Visualization and App Control licenses are also included with the SonicWALL Security Services license bundle. Note that the feature must be enabled in the SonicOS management interface to become active.
 
Administrators can configure policy settings for individual signatures without influencing other signatures of the same application.
 
Application Control configuration screens are moved to the Firewall menu in the SonicOS management interface, consolidating all Firewall and Application Control access rules and policies in the same area.

Application Control functionality can be compared to three main categories of products:

 
Standalone proxy appliances
 
Application proxies integrated into firewall VPN appliances
 
Standalone IPS appliances with custom signature support

Standalone proxy appliances are typically designed to provide granular access control for a specific protocol. SonicWALL Application Control provides granular, application level access control across multiple protocols, including HTTP, FTP, SMTP, and POP3. Because Application Control runs on your SonicWALL firewall, you can use it to control both inbound and outbound traffic, unlike a dedicated proxy appliance that is typically deployed in only one direction. Application Control provides better performance and scalability than a dedicated proxy appliance because it is based on SonicWALL’s proprietary Deep Packet Inspection technology.

Today’s integrated application proxies do not provide granular, application level access control, application layer bandwidth management, and digital rights management functionality. As with dedicated proxy appliances, SonicWALL Application Control provides much higher performance and far greater scalability than integrated application proxy solutions.

While some standalone IPS appliances provide protocol decoding support, none of these products supports granular, application level access control, application layer bandwidth management, and digital rights management functionality.

In comparing Application Control to SonicWALL Email Security, there are benefits to using either. Email Security only works with SMTP, but it has a very rich policy space. Application Control works with SMTP, POP3, HTTP, FTP and other protocols, is integrated into SonicOS on the firewall, and has higher performance than Email Security. However, Application Control does not offer all the policy options for SMTP that are provided by Email Security.

How Does Application Control Work?

Application Control utilizes SonicOS Deep Packet Inspection to scan application layer network traffic as it passes through the gateway and locate content that matches configured applications. When a match is found, these features perform the configured action. When you configure App Control policies, you create global rules that define whether to block or log the application, which users, groups, or IP address ranges to include or exclude, and a schedule for enforcement. Additionally, you can create App Rules policies that define the type of applications to scan, the direction, the content or keywords to match, optionally the user or domain to match, and the action to perform.

The following sections describe the main components of Application Control:

 
App Control Policies
 
App Rules Policies
 
Match Objects
 
Application List Objects
 
Action Objects
 
Email Address Objects

App Control Policies

The configuration method on the Firewall > App Control Advanced page allows granular control of specific categories, applications, or signatures. This includes granular logging control, granular inclusion and exclusion of users, groups, or IP address ranges, and schedule configuration. The settings here are global policies and independent from any custom App Rules policy. The Firewall > App Control Advanced page is shown below.

You can configure the following settings on this page:

 
Select a category, an application, or a signature.
 
Select blocking, logging, or both as the action.
 
Specify users, groups, or IP address ranges to include in or exclude from the action.
 
Set a schedule for enforcing the controls.

While these application control settings are independent from App Rules policies, you can also create application match objects for any of the categories, applications, or signatures available here or on the Firewall > Match Objects page, and use those match objects in an App Rules policy. This allows you to use the wide array of actions and other configuration settings available with Application Control. See the “Application List Objects” section for more information about this policy-based user interface for application control.

App Rules Policies

You can use Application Control to create custom App Rules policies to control specific aspects of traffic on your network. A policy is a set of match objects, properties, and specific prevention actions.When you create a policy, you first create a match object, then select and optionally customize an action, then reference these when you create the policy.

In the Firewall > App Rules page, you can access the Policy Settings screen, shown below for a Policy Type of SMTP Client. The screen changes depending on the Policy Type you select.

Some examples of policies include:

 
Block applications for activities such as gambling
 
Disable .exe and .vbs email attachments
 
Do not allow the Mozilla browser on outgoing HTTP connections
 
Do not allow outgoing email or MS Word attachments with the keywords “SonicWALL Confidential”, except from the CEO and CFO
 
Do not allow outgoing email that includes a graphic or watermark found in all confidential documents

When you create a policy, you select a policy type. Each policy type specifies the values or value types that are valid for the source, destination, match object type, and action fields in the policy. You can further define the policy to include or exclude specific users or groups, select a schedule, turn on logging, and specify the connection side as well as basic or advanced direction types. A basic direction type simply indicates inbound or outbound. An advanced direction type allows zone to zone direction configuration, such as from the LAN to the WAN.

The following table describes the characteristics of the available App Rules policy types.

 

Policy Type
Valid Source Service / Default
Valid Destination Service / Default
Valid Match Object Type

App Control Content

Policy using dynamic Application Control related objects for any application layer protocol

N/A

N/A

Application Category List, Application List, Application Signature List

Reset/Drop, Bypass DPI, Packet Monitor, Manage Bandwidth, No Action

N/A

CFS

Policy for content filtering

N/A

N/A

CFS Category List

CFS Block Page, Packet Monitor, Manage Bandwidth, No Action

N/A

Custom Policy

Policy using custom objects for any application layer protocol; can be used to create IPS-style custom signatures

Any / Any

Any / Any

Custom Object

Reset/Drop, Bypass DPI, Packet Monitor, Manage Bandwidth, No Action

Client Side, Server Side, Both

FTP Client

Any FTP command transferred over the FTP control channel

Any / Any

FTP Control / FTP Control

FTP Command, FTP Command + Value, Custom Object

Reset/Drop, Bypass DPI, Packet Monitor, No Action

Client Side

FTP Client File Upload Request

An attempt to upload a file over FTP (STOR command)

Any / Any

FTP Control / FTP Control

Filename, file extension

Reset/Drop, Bypass DPI, Packet Monitor, Manage Bandwidth, No Action

Client Side

FTP Client File Download Request

An attempt to download a file over FTP (RETR command)

Any / Any

FTP Control / FTP Control

Filename, file extension

Reset/Drop, Bypass DPI, Packet Monitor, Manage Bandwidth, No Action

Client Side

FTP Data Transfer Policy

Data transferred over the FTP Data channel

Any / Any

Any / Any

File Content Object

Reset/Drop, Bypass DPI, Packet Monitor, No Action

Both

HTTP Client

Policy which is applicable to Web browser traffic or any HTTP request that originates on the client

Any / Any

Any / HTTP (configurable)

HTTP Host, HTTP Cookie, HTTP Referrer, HTTP Request Custom Header, HTTP URI Content, HTTP User Agent, Web Browser, File Name, File Extension Custom Object

Reset/Drop, Bypass DPI, Packet Monitor*, Manage Bandwidth, No Action

 

*Packet Monitor action not supported for File Name or File Extension Custom Object

Client Side

HTTP Server

Response originated by an HTTP Server

Any / HTTP (configurable)

Any / Any

ActiveX Class ID, HTTP Set Cookie, HTTP Response Custom Header, Custom Object

Reset/Drop, Bypass DPI, Packet Monitor, Manage Bandwidth, No Action

Server Side

IPS Content

Policy using dynamic Intrusion Prevention related objects for any application layer protocol

N/A

N/A

IPS Signature Category List, IPS Signature List

Reset/Drop, Bypass DPI, Packet Monitor, Manage Bandwidth, No Action

N/A

POP3 Client

Policy to inspect traffic generated by a POP3 client; typically useful for a POP3 server admin

Any / Any

POP3 (Retrieve Email) / POP3 (Retrieve Email)

Custom Object

Reset/Drop, Bypass DPI, Packet Monitor, No Action

Client Side

POP3 Server

Policy to inspect email downloaded from a POP3 server to a POP3 client; used for email filtering

POP3 (Retrieve Email) / POP3 (Retrieve Email)

Any / Any

Email Body, Email CC, Email From, Email To, Email Subject, File Name, File Extension, MIME Custom Header

Reset/Drop, Disable attachment, Bypass DPI, no action

Server Side

SMTP Client

Policy applies to SMTP traffic that originates on the client

Any / Any

SMTP (Send Email)/ SMTP (Send Email)

Email Body, Email CC, Email From, Email To, Email Size, Email Subject, Custom Object, File Content, File Name, File Extension, MIME Custom Header,

Reset/Drop, Block SMTP E-Mail Without Reply, Bypass DPI, Packet Monitor, No Action

Client Side

Match Objects

Match objects represent the set of conditions which must be matched in order for actions to take place. This includes the object type, the match type (exact, partial, prefix, or suffix), the input representation (text or hexadecimal), and the actual content to match. Match objects were referred to as application objects in previous releases.

Hexadecimal input representation is used to match binary content such as executable files, while text input representation is used to match things like file or email content. You can also use hexadecimal input representation for binary content found in a graphic image. Text input representation could be used to match the same graphic if it contains a certain string in one of its properties fields.

The maximum size for a match object is 8192 (8K) bytes. Because Application Control matches data at wire speeds, match objects do not provide matching for regular expressions. You can use a proxy server for this functionality.

The File Content match object type provides a way to match a pattern within a compressed file. This type of match object can only be used with FTP Data Transfer or SMTP Client Policies.

The following table describes the supported match object types.

 

Negative Matching

ActiveX ClassID

Class ID of an Active-X component. For example, ClassID of Gator Active-X component is “c1fb8842-5281-45ce-a271-8fd5f117ba5f”

Exact

No

None

Application Category List

Allows specification of application categories, such as Multimedia., P2P, or Social Networking

N/A

No

None

Application List

Allows specification of individual applications within the application category that you select

N/A

No

None

Application Signature List

Allows specification of individual signatures for the application and category that you select

N/A

No

None

CFS Allow/ Forbidden List

Allows specification of allowed and forbidden domains for Content Filtering

Exact, Partial, Prefix, Suffix

No

None

CFS Category List

Allows selection of one or more Content Filtering categories

N/A

No

A list of 64 categories is provided to choose from

Custom Object

Allows specification of an IPS-style custom set of conditions.

Exact

No

There are 4 additional, optional parameters that can be set: offset (describes from what byte in packet payload we should start matching the pattern – starts with 1; helps minimize false positives in matching), depth (describes at what byte in the packet payload we should stop matching the pattern – starts with 1), minimum payload size and maximum payload size.

Email Body

Any content in the body of an email.

Partial

No

None

Email CC (MIME Header)

Any content in the CC MIME Header.

Exact, Partial, Prefix, Suffix

Yes

None

Email From (MIME Header)

Any content in the From MIME Header.

Exact, Partial, Prefix, Suffix

Yes

None

Email Size

Allows specification of the maximum email size that can be sent.

N/A

No

None

Email Subject (MIME Header)

Any content in the Subject MIME Header.

Exact, Partial, Prefix, Suffix

Yes

None

Email To (MIME Header)

Any content in the To MIME Header.

Exact, Partial, Prefix, Suffix

Yes

None

MIME Custom Header

Allows for creation of MIME custom headers.

Exact, Partial, Prefix, Suffix

Yes

A Custom header name needs to be specified.

File Content

Allows specification of a pattern to match in the content of a file. The pattern will be matched even if the file is compressed.

Partial

No

‘Disable attachment’ action should never be applied to this object.

Filename

In cases of email, this is an attachment name. In cases of HTTP, this is a filename of an uploaded attachment to the Web mail account. In cases of FTP, this is a filename of an uploaded or downloaded file.

Exact, Partial, Prefix, Suffix

Yes

None

Filename Extension

In cases of email, this is an attachment filename extension. In cases of HTTP, this is a filename extension of an uploaded attachment to the Web mail account. In cases of FTP, this is a filename extension of an uploaded or downloaded file.

Exact

Yes

None

FTP Command

Allows selection of specific FTP commands.

N/A

No

None

FTP Command + Value

Allows selection of specific FTP commands and their values.

Exact, Partial, Prefix, Suffix

Yes

None

HTTP Cookie Header

Allows specification of a Cookie sent by a browser.

Exact, Partial, Prefix, Suffix

Yes

None

HTTP Host Header

Content found inside of the HTTP Host header. Represents hostname of the destination server in the HTTP request, such as www.google.com .

Exact, Partial, Prefix, Suffix

Yes

None

HTTP Referrer Header

Allows specification of content of a Referrer header sent by a browser – this can be useful to control or keep stats of which Web sites redirected a user to customer’s Web site.

Exact, Partial, Prefix, Suffix

Yes

None

HTTP Request Custom Header

Allows creation of custom HTTP Request headers.

Exact, Partial, Prefix, Suffix

Yes

A Custom header name needs to be specified.

HTTP Response Custom Header

Allows creation of custom HTTP Response headers.

Exact, Partial, Prefix, Suffix

Yes

A Custom header name needs to be specified.

HTTP Set Cookie Header

Set-Cookie headers. Provides a way to disallow certain cookies to be set in a browser.

Exact, Partial, Prefix, Suffix

Yes

None

HTTP URI Content

Any content found inside of the URI in the HTTP request.

Exact, Partial, Prefix, Suffix

No

None

HTTP User-Agent Header

Any content inside of a User-Agent header. For example: User-Agent: Skype.

Exact, Partial, Prefix, Suffix

Yes

None

Web Browser

Allows selection of specific Web browsers (MSIE, Netscape, Firefox, Safari, Chrome).

N/A

Yes

None

IPS Signature Category List

Allows selection of one or more IPS signature groups. Each group contains multiple pre-defined IPS signatures.

N/A

No

None

IPS Signature List

Allows selection of one or more specific IPS signatures for enhanced granularity.

N/A

No

None

You can see the available types of match objects in a drop-down list in the Match Object Settings screen.

In the Match Object screen, you can add multiple entries to create a list of content elements to match. All content that you provide in a match object is case-insensitive for matching purposes. A hexadecimal representation is used to match binary content. You can use a hex editor or a network protocol analyzer like Wireshark to obtain hex format for binary files. For more information about these tools, see the following sections:

 
Wireshark
 
Hex Editor

You can use the Load From File button to import content from predefined text files that contain multiple entries for a match object to match. Each entry in the file must be on its own line. The Load From File feature allows you to easily move Application Control settings from one SonicWALL security appliance to another.

Multiple entries, either from a text file or entered manually, are displayed in the List area. List entries are matched using the logical OR, so if any item in the list is matched, the action for the policy is executed.

A match object can include a total of no more than 8000 characters. If each element within a match object contains approximately 30 characters, then you can enter about 260 elements. The maximum element size is 8000 bytes.

Negative Matching

Negative matching provides an alternate way to specify which content to block. You can enable negative matching in a match object when you want to block everything except a particular type of content. When you use the object in a policy, the policy will execute actions based on absence of the content specified in the match object. Multiple list entries in a negative matching object are matched using the logical AND, meaning that the policy action is executed only when all specified negative matching entries are matched.

Although all App Rules policies are DENY policies, you can simulate an ALLOW policy by using negative matching. For instance, you can allow email .txt attachments and block attachments of all other file types. Or you can allow a few types, and block all others.

Not all match object types can utilize negative matching. For those that can, you will see the Enable Negative Matching checkbox on the Match Object Settings screen.

 

Application List Objects

The Firewall > Match Objects page also contains the Add Application List Object button, which opens the Create Match Object screen. This screen provides two tabs:

 
Application – You can create an application filter object on this tab. This screen allows selection of the application category, threat level, type of technology, and attributes. After selections are made, the list of applications matching those criteria is displayed. The Application tab provides another way to create a match object of the Application List type.
 
Category – You can create a category filter object on this tab. A list of application categories and their descriptions are provided. The Category page offers another way to create a match object of the Application Category List type.

Application Filters

The Application tab provides a list of applications for selection. You can control which applications are displayed by selecting one or more application categories, threat levels, and technologies. You can also search for a keyword in all application names by typing it into the Search field near the top right of the display. For example, type in “bittorrent” into the Search field and click the Search icon to find multiple applications with “bittorrent” (not case-sensitive) in the name.

When the application list is reduced to a list that is focussed on your preferences, you can select the individual applications for your filter by clicking the Plus icon next to them, and then save your selections as an application filter object with a custom name or an automatically generated name. The image below shows the screen with all categories, threat levels, and technologies selected, but before any individual applications have been chosen.

As you select the applications for your filter, they appear in the Application Group field on the right. You can edit the list in this field by deleting individual items or by clicking the eraser to delete all items. The image below shows several applications in the Application Group field. The selected applications are also marked with a green checkmark icon in the application list on the left side.

When finished selecting the applications to include, you can type in a name for the object in the Match Object Name field (first, clear the Auto-generate match object name checkbox) and click the Save Application Match Object button. You will see the object name listed on the Firewall > Match Objects page with an object type of Application List . This object can then be selected when creating an App Rules policy.

Match Objects created using the Auto-generate match object name option display a tilde (~ ) as the first character of the object name.

Category Filters

The Category tab provides a list of application categories for selection. You can select any combination of categories and then save your selections as a category filter object with a custom name. The image below shows the screen with the description of the IM category displayed.

You can hover your mouse pointer over each category in the list to see a description of it. To create a custom category filter object, simply type in a name for the object in the Match Object Name field (first, clear the Auto-generate match object name checkbox), select one or more categories, and click the Save Category Match Object button. You will see the object name listed on the Firewall > Match Objects page with an object type of Application Category List . This object can then be selected when creating an App Rules policy.

Match Objects created using the Auto-generate match object name option display a tilde (~ ) as the first character of the object name.

Action Objects

Action Objects define how the App Rules policy reacts to matching events. You can choose a customizable action or select one of the predefined, default actions.

The predefined actions are:

 
Block SMTP Email Without Reply
 
BWM High
 
BWM Low
 
BWM Medium
 
Bypass DPI
 
CFS block page
 
No Action
 
Packet Monitor
 
Reset / Drop

The customizable actions are:

 
Block SMTP Email - Send Error Reply
 
Disable Email Attachment - Add Text
 
Email - Add Text
 
FTP Notification Reply
 
HTTP Block Page
 
HTTP Redirect
 
Bandwidth Management

See the table below for descriptions of these action types.

Note that only the customizable actions are available for editing in the Action Object Settings window, shown in the image below. The predefined actions cannot be edited or deleted. When you create a policy, the Policy Settings screen provides a way for you to select from the predefined actions along with any customized actions that you have defined.

The following table describes the available action types.

 

Predefined or Custom

Block SMTP Email Without Reply

Blocks SMTP email, but to the sender it looks like email was successfully sent.

Predefined

BWM High

Manages inbound and outbound bandwidth, guarantees a high level of bandwidth availability defined as 90% of total available bandwidth, allows high bandwidth usage up to a maximum of 90% of total available bandwidth1 ; sets a priority of zero2 , and enables bandwidth usage tracking. You can view these settings and the usage in the Action Properties tooltip by mousing over the BWM action of a policy on the Firewall > App Rules page.

Predefined

BWM Low

Manages inbound and outbound bandwidth, guarantees a low level of bandwidth availability defined as 20% of total available bandwidth, allows bandwidth usage up to a maximum of 20% of total available bandwidtha ; sets a priority of zerob , and enables bandwidth usage tracking. You can view these settings and the usage in the Action Properties tooltip by mousing over the BWM action of a policy on the Firewall > App Rules page.

Predefined

BWM Medium

Manages inbound and outbound bandwidth, guarantees a medium level of bandwidth availability defined as 50% of total available bandwidth, allows bandwidth usage up to a maximum of 50% of total available bandwidtha ; sets a priority of zerob , and enables bandwidth usage tracking. You can view these settings and the usage in the Action Properties tooltip by mousing over the BWM action of a policy on the Firewall > App Rules page.

Predefined

Bypass DPI

Bypasses Deep Packet Inspection components IPS, GAV, Anti-Spyware and Application Control. This action persists for the duration of the entire connection as soon as it is triggered. Special handling is applied to FTP control channels that are never bypassed for Application Control inspection. This action supports proper handling of the FTP data channel. Note that Bypass DPI does not stop filters that are enabled on the Firewall Settings > SSL Control page.

Predefined

CFS block page

Blocks access to the Web page and displays a pre- formatted ‘blocked content’ page.

Predefined

No Action

Policies can be specified without any action. This allows “log only” policy types.

Predefined

Packet Monitor

Use the SonicOS Packet Monitor capability to capture the inbound and outbound packets in the session, or if mirroring is configured, to copy the packets to another interface. The capture can be viewed and analyzed with Wireshark.

Predefined

Reset / Drop

For TCP, the connection will be reset. For UDP, the packet will be dropped.

Predefined

Block SMTP Email - Send Error Reply

Blocks SMTP email and notifies the sender with a customized error message.

Custom

Disable Email Attachment - Add Text

Disables attachment inside of an email and adds customized text.

Custom

Email - Add Text

Appends custom text at the end of the email.

Custom

FTP Notification Reply

Sends text back to the client over the FTP control channel without terminating the connection.

Custom

HTTP Block Page

Allows a custom HTTP block page configuration with a choice of colors.

Custom

HTTP Redirect

Provides HTTP Redirect functionality. For example, if someone would like to redirect people to the Google Web site, the customizable part will look like: http://www.google.com
If an HTTP Redirect is sent from Application Control to a browser that has a form open, the information in the form will be lost.

Custom

Bandwidth Management

Allows definition of bandwidth management constraints with same semantics as Access Rule BWM policy definition.

Custom


1

Total available bandwidth is defined by the values entered for Available Interface Egress/Ingress Bandwidth when configuring the WAN interface from the Network > Interfaces page. See “Configuring Application Layer Bandwidth Management” section for more information.

2

Application Layer Bandwidth Management

Application layer bandwidth management (BWM) allows you to create policies that regulate bandwidth consumption by specific file types within a protocol, while allowing other file types to use unlimited bandwidth. This enables you to distinguish between desirable and undesirable traffic within the same protocol. Application layer bandwidth management is supported for all Application matches, as well as custom App Rules policies using HTTP client, HTTP Server, Custom, and FTP file transfer types. For details about policy types, see App Rules Policies .

For example, as an administrator you might want to limit .mp3 and executable file downloads during work hours to no more than 1 Mbps. At the same time, you want to allow downloads of productive file types such as .doc or .pdf up to the maximum available bandwidth, or even give the highest possible priority to downloads of the productive content. As another example, you might want to limit bandwidth for a certain type of peer-to-peer (P2P) traffic, but allow other types of P2P to use unlimited bandwidth. Application layer bandwidth management allows you to create policies to do this.

Application layer bandwidth management functionality is supported with three predefined BWM actions (High, Medium, and Low) available when adding a policy from the Firewall > App Rules page, and a customizable Bandwidth Management type action, available when adding a new action from the Firewall > Action Objects screen.

When configuring a Bandwidth Management action, you can select either Per Action or Per Policy , as shown in the image below. Per Policy means that when you create a limit of 10 Mbps in an Action Object, and three different policies use the Action Object, then each policy can consume up to 10 Mbps of bandwidth. Per Action means that the three policies combined can only use 10 Mbps.

When using Per Action, multiple policies are subject to a single aggregate bandwidth management setting when they share the same action. For example, consider the following two App Rules policies:

 
One manages the bandwidth for downloading executable files
 
Another manages the bandwidth for P2P applications traffic

If these two policies share the same bandwidth management Action (500 Kbit/sec max bandwidth):

 
Using the Per Action aggregation method, the downloads of executable files and traffic from P2P applications combined cannot exceed 500 Kbit/sec.
 
Using the Per Policy bandwidth aggregation method, a bandwidth of 500 Kbit/sec is allowed for executable file downloads while concurrent P2P traffic is also allowed a bandwidth of 500 Kbit/sec.

The predefined BWM High, BWM Medium, and BWM Low actions are all Per Action. In releases previous to SonicOS 5.8, all Bandwidth Management actions were implicitly set to Per Policy, but now you have a choice.

Application layer bandwidth management configuration is handled in the same way as the Ethernet bandwidth management configuration associated with Firewall > Access Rules. However, with Application Control you can specify all content type, which you cannot do with access rules.

 
Note
Bandwidth management policies defined with Firewall > Access Rules always have priority over application layer bandwidth management policies. Thus, if an access rule bandwidth management policy is applied to a certain connection, then an application layer bandwidth management policy will never be applied to that connection.

Packet Monitoring

When the predefined Packet Monitor action is set for a policy, SonicOS will capture or mirror the traffic according to the settings you have configured on the System > Packet Monitor page. The default is to create a capture file, which you can view with Wireshark.

To customize the action, you can click Configure on the System > Packet Monitor page and select Enable Filter based on the firewall rule on the Monitor Filter tab. This works for both App Rules policies and for Firewall Access Rules, and allows you to specify configuration or filtering for what to capture or mirror. You can download the capture in different formats and look at it in a Web page, for example.

To set up mirroring, go to the Mirror tab and pick an interface to which to send the mirrored traffic in the Mirror filtered packets to Interface (NSA platforms only) field under Local Mirroring Settings. You can also configure one of the Remote settings. This allows you to mirror the application packets to another computer and store everything in the hard disk. For example, you could capture everyone’s MSN Instant Messenger traffic and read the conversations.

Email Address Objects

Application Control allows the creation of custom email address lists as email address objects. You can only use email address objects in an SMTP client policy configuration. Email address objects can represent either individual users or the entire domain. You can also create an email address object that represents a group by adding a list of individual addresses to the object. This provides a way to easily include or exclude a group of users when creating an SMTP client policy.

For example, you can create an email address object to represent the support group:

After you define the group in an email address object, you can create an SMTP client policy that includes or excludes the group.

In the screenshot below, the settings exclude the support group from a policy that prevents executable files from being attached to outgoing email. You can use the email address object in either the MAIL FROM or RCPT TO fields of the SMTP client policy. The MAIL FROM field refers to the sender of the email. The RCPT TO field refers to the intended recipient.

Although Application Control cannot extract group members directly from Outlook Exchange or similar applications, you can use the member lists in Outlook to create a text file that lists the group members. Then when you create an email address object for this group, you can use the Load From File button to import the list from your text file. Be sure that each email address is on a line by itself in the text file.

Licensing Application Control

Application Intelligence and Control has two components:

 
The Intelligence component is licensed as App Visualization , and provides identification and reporting of application traffic on the Dashboard > Real-Time Monitor and App Flow Monitor pages in SonicOS 5.8.
 
The Control component is licensed as App Control , and allows you to create and enforce custom App Control and App Rules policies for logging, blocking, and bandwidth management of application traffic handled by your network.

App Visualization and App Control are licensed together in a bundle with other security services including SonicWALL Gateway Anti-Virus (GAV), Anti-Spyware, and Intrusion Prevention Service (IPS).

 
Note
Upon registration on MySonicWALL, or when you load SonicOS 5.8 onto a registered SonicWALL device, supported SonicWALL appliances begin an automatic 30-day trial license for App Visualization and App Control, and application signatures are downloaded to the appliance.

A free 30-day trial is also available for the other security services in the bundle, but it is not automatically enabled as it is for App Visualization and App Control. You can start the additional free trials on the individual Security Services pages in SonicOS, or on MySonicWALL.

Once the App Visualization feature is manually enabled on the Log > Flow Reporting page (see the screenshot below), you can view real-time application traffic on the Dashboard > Real-Time Monitor page and application activity in other Dashboard pages for the identified/classified flows from the SonicWALL application signature database.

To begin using App Control, you must enable it on the Firewall > App Control Advanced page. See the screenshot below.

To create policies using App Rules (included with the App Control license), select Enable App Rules on the Firewall > App Rules page. See the screenshot below.

The SonicWALL Licensing server provides the App Visualization and App Control license keys to the SonicWALL device when you begin a 30-day trial (upon registration) or purchase a Security Services license bundle.

Licensing is available on www.mysonicwall.com on the Service Management - Associated Products page under GATEWAY SERVICES.

The Security Services license bundle includes licenses for the following subscription services:

 
App Visualization
 
App Control
 
Gateway Anti-Virus
 
Gateway Anti-Spyware
 
Intrusion Prevention Service

Application signature updates and signature updates for other Security Services are periodically downloaded to the SonicWALL appliance as long as these services are licensed.

 
Note
If you disable Visualization in the SonicOS management interface, application signature updates are discontinued until the feature is enabled again.

When High Availability is configured between two SonicWALL appliances, the appliances can share the Security Services license. To use this feature, you must register the SonicWALL appliances on MySonicWALL as Associated Products. Both appliances must be the same SonicWALL model.

 
Note
For a High Availability pair, even if you first register your appliances on MySonicWALL, you must individually register both the Primary and the Backup appliances from the SonicOS management interface while logged into the individual management IP address of each appliance. This allows the Backup unit to synchronize with the SonicWALL license server and share licenses with the associated Primary appliance. When Internet access is restricted, you can manually apply the shared licenses to both appliances.