Spam Filtering

ProSight Email Guard from Progent uses the services and infrastructure of leading data security companies to provide centralized management and comprehensive protection for all your inbound and outbound email. The hybrid architecture of ProSight Email Guard combines a Cloud Protection Layer with an on-premises security gateway appliance to deliver world-class defense against spam, viruses, spoofing, phishing, spyware, Denial of Service (DoS) attacks, Directory Harvest Attacks (DHAs), and other email-borne threats.

ProSight Email Guard's Cloud Protection Layer acts as a first line of defense and keeps the vast majority of threats from reaching your security perimeter. This reduces your vulnerability to external attacks and conserves system resources. Email Guard's on-premises security gateway provides a deeper layer of inspection for inbound email. For outbound email, the local security gateway offers anti-virus and anti-spam filtering, policy-based Data Loss Prevention (DLP), Data Leakage Protection, Content Filtering and outbound email encryption. The local email security gateway can also manage your Exchange Server deployment to monitor and protect internal email traffic that never reaches your security gateway.

ProSight Email Guard works with any email platform and offers enhanced features for Exchange Server.

The architecture of the ProSight Email Guard solution includes four main components that stand between the Internet and the email server at your data center:

• Update Center
• Cloud Protection Layer
• Email Guard Security Gateway Appliance
• Message Center

Update Center
The Update Center is a technology center staffed 24x7x365 by security experts who gather emails, URLs, binaries and other data collected from thousands of collection points worldwide, aggregate and analyze this information, and develop defenses, rules and signatures to update ProSight Email Guard's defense mechanism in order to provide zero-hour protection against the latest email-borne threats. Advanced filtering techniques and heuristic rules analysis used by the Update Center include reputation analysis, intent analysis, and predictive sender profiling. The result is a spam and virus filtering solution that blocks a very high percentage of threats yet delivers a very low number of false positives.

Cloud Protection Layer
The Cloud Protection Layer, which is kept current by the Update Center, provides spam and virus prefiltering using advanced technologies that include anti-fraud intelligence and blocking polymorphic viruses that can change their signatures to escape detection. Made up of multiple hardened datacenters worldwide, the Cloud Protection Layer has the capacity to handle Denial of Service attacks as well as email surges that occur during specific periods of the day. Because this cloud-based service stands between the Internet and the Email Guard security gateway, the majority of malicious email can be eliminated before it reaches your security perimeter. To help with disaster recovery and email continuity, the Cloud Protection Layer offers spooling. If your on-premises data center is disrupted, the spooling feature can store all inbound email in the cloud for up to 96 hours or direct it to an alternate destination while you repair the problem.

ProSight Email Guard Security Gateway Hardware Appliance
The ProSight Email Guard Security Gateway is a physical rack-mountable appliance that provides comprehensive protection for inbound, outbound and internal email. The gateway is automatically updated in real time by the Update Center without requiring management intervention. One of the gateway's deep inspection features is a multi-pass OCR engine that protects against image spam, where text is embedded within a graphic in order to hide content from spam filters. Another feature for filtering inbound email is link protection, which automatically evaluates and rewrites fraudulent URLs contained in a message. A plug-in agent for Microsoft Exchange Server offers virus protection for internal email traffic that does not access the gateway, for example emails from Outlook Web Access.

The ProSight Email Guard Security Gateway offers Data Loss Prevention (DLP) by allowing administrators to enforce content policies for outbound email in order to keep sensitive corporate information from being inadvertently leaked. The gateway can also be configured to block invalid bounce messages, which are outbound non-delivery reports to forged email addresses. In addition, the gateway offers a variety of encryption features for outbound email and supports inbound and outbound rate control. The Email Guard Security Gateway is available in several models to match your capacity requirements and security needs and can be clustered for higher performance and availability.

Message Center
The Message Center is a cloud-based service for encrypting outbound email. Emails that match policy are sent securely from the Email Guard Security Gateway to the Message Center. At the Message Center, the sender's email is encrypted using Advanced Encryption Service with a 256-bit cipher (AES-256) and stored for retrieval. The Message Centers sends the recipient a notification that includes a link to visit in order to retrieve the message. The link requires a web browser using HTTPS. The recipient selects a password and the Message Center delivers the encrypted message.

The recipient only needs to establish a password for the first encrypted email received from the message center. Any replies are also sent via the Message Center to maintain security. Encryption key management is handled automatically by the Message Center, and the keys used to encrypt the data are stored in separate areas to provide physical security. Email traffic between the Email Guard Security Gateway and the Message Center and between the Message Center and the recipient are encrypted via SMTP over TLS.

In addition to policy-based encryption, Email Guard also provides an add-in for Microsoft Exchange Server that allows users to specify encryption from within Outlook.

Management Features
The ProSight Email Guard security gateway is integrated with a web-based management portal that provides a simple, centralized interface for viewing and managing all devices, services, policies and configurations. The cloud management tool offers global, domain-level, and individual user policy control. User-level policy management includes block lists, allow lists, quarantining, scoring thresholds, tagging and Bayesian analysis. At the domain level, you can manage policy for inbound and outbound quarantines, outbound encryption, plus block and allow lists based on IP address or sender/recipient email address or domain. Other management features include reports, graphs, statistics; recipient validation via LDAP; support for multiple domains; and delegated domain administration and help desk role.

Download the ProSight Email Guard Datasheet
To view the ProSight Email Guard datasheet, click: ProSight Email Guard Cloud-managed Services Datasheet (94 Kb PDF file).

Other Managed Services Available from Progent
In addition to ProSight Email Guard, Progent offers other affordably-priced ProSight managed service packages that address key components of your information system such as security, backup/recovery, virtual server hosting, IT documentation management, and network infrastructure management. By partnering with leading technology innovators, Progent can offer small and mid-size businesses the benefits of the same advanced technology used by global enterprises. Managed services available from Progent include:

• ProSight Active Security Monitoring: Endpoint Protection and Ransomware Defense
  Progent's ProSight Active Security Monitoring (ASM) is an endpoint protection (EPP) service that utilizes next generation behavior-based analysis technology to guard physical and virtual endpoints against modern malware assaults such as ransomware and file-less exploits, which easily get by traditional signature-matching AV products. ProSight Active Security Monitoring safeguards on-premises and cloud-based resources and offers a unified platform to automate the entire threat progression including filtering, detection, mitigation, remediation, and forensics. Top features include one-click rollback using Windows Volume Shadow Copy Service and automatic system-wide immunization against new attacks. Read more about Progent's ProSight Active Security Monitoring (ASM) next-generation endpoint protection and ransomware recovery.

• ProSight Enhanced Security Protection: Physical and Virtual Endpoint Security and Microsoft Exchange Filtering
  ProSight Enhanced Security Protection services deliver affordable multi-layer security for physical servers and virtual machines, desktops, mobile devices, and Exchange email. ProSight ESP uses adaptive security and advanced heuristics for continuously monitoring and responding to security assaults from all vectors. ProSight ESP provides two-way firewall protection, intrusion alarms, device control, and web filtering through cutting-edge tools packaged within a single agent managed from a unified console. Progent's data protection and virtualization consultants can help your business to design and configure a ProSight ESP environment that meets your organization's specific requirements and that allows you prove compliance with legal and industry data protection regulations. Progent will assist you specify and configure policies that ProSight ESP will manage, and Progent will monitor your network and react to alarms that require urgent attention. Progent can also assist your company to install and test a backup and restore solution like ProSight Data Protection Services (DPS) so you can get back in business rapidly from a potentially disastrous security attack like ransomware. Learn more about Progent's ProSight Enhanced Security Protection unified endpoint protection and Microsoft Exchange email filtering.

• ProSight Data Protection Services: Managed Backup and Disaster Recovery
  ProSight Data Protection Services from Progent provide small and mid-sized organizations a low cost and fully managed service for reliable backup/disaster recovery. Available at a low monthly cost, ProSight Data Protection Services automates and monitors your backup processes and allows fast recovery of critical files, applications and virtual machines that have become unavailable or corrupted as a result of hardware breakdowns, software glitches, natural disasters, human error, or malware attacks such as ransomware. ProSight DPS can help you protect, retrieve and restore files, folders, apps, system images, as well as Microsoft Hyper-V and VMware virtual machine images. Critical data can be backed up on the cloud, to an on-promises device, or mirrored to both. Progent's cloud backup consultants can provide advanced expertise to set up ProSight DPS to be compliant with government and industry regulatory requirements such as HIPAA, FIRPA, and PCI and, when necessary, can assist you to recover your critical data. Find out more about ProSight Data Protection Services Managed Cloud Backup and Recovery.

• ProSight WAN Watch: Network Infrastructure Management
  ProSight WAN Watch is a network infrastructure management service that makes it simple and inexpensive for small and mid-sized businesses to diagram, monitor, enhance and troubleshoot their connectivity hardware such as routers and switches, firewalls, and wireless controllers as well as servers, printers, client computers and other networked devices. Incorporating state-of-the-art RMM technology, WAN Watch ensures that network maps are always current, copies and displays the configuration information of almost all devices on your network, tracks performance, and sends notices when potential issues are detected. By automating complex management and troubleshooting processes, WAN Watch can cut hours off common chores such as network mapping, expanding your network, finding devices that require critical software patches, or resolving performance issues. Learn more details about ProSight WAN Watch infrastructure management consulting.

• ProSight LAN Watch: Server and Desktop Monitoring and Management
  ProSight LAN Watch is Progent’s server and desktop remote monitoring service that uses state-of-the-art remote monitoring and management (RMM) technology to keep your network operating at peak levels by tracking the health of vital assets that power your business network. When ProSight LAN Watch uncovers a problem, an alert is sent automatically to your designated IT management staff and your assigned Progent consultant so all potential issues can be addressed before they can disrupt productivity. Learn more details about ProSight LAN Watch server and desktop remote monitoring services.

• ProSight Virtual Hosting: Hosted Virtual Machines at Progent's Tier III Data Center
  With Progent's ProSight Virtual Hosting service, a small or mid-size business can have its key servers and applications hosted in a protected Tier III data center on a fast virtual host set up and managed by Progent's IT support professionals. Under the ProSight Virtual Hosting service model, the client owns the data, the operating system software, and the applications. Since the environment is virtualized, it can be moved easily to an alternate hosting environment without requiring a lengthy and difficult reinstallation procedure. With ProSight Virtual Hosting, your business is not tied one hosting provider. Learn more about ProSight Virtual Hosting services.

• ProSight IT Asset Management: Network Documentation Management
  Progent's ProSight IT Asset Management service is an IT infrastructure documentation management service that allows you to create, update, retrieve and protect information about your IT infrastructure, procedures, applications, and services. You can instantly locate passwords or IP addresses and be alerted about upcoming expirations of SSLs ,domains or warranties. By cleaning up and organizing your network documentation, you can save up to 50% of time thrown away looking for critical information about your IT network. ProSight IT Asset Management features a common location for holding and collaborating on all documents required for managing your business network like recommended procedures and How-To's. ProSight IT Asset Management also supports a high level of automation for gathering and relating IT data. Whether you’re planning enhancements, doing regular maintenance, or reacting to an emergency, ProSight IT Asset Management delivers the knowledge you need the instant you need it. Find out more about Progent's ProSight IT Asset Management service.

ProSight Network Audits
Progent's ProSight Network Audits offer a fast and low-cost alternative for small and mid-size organizations to get an unbiased assessment of the overall health of their information system. Powered by a selection of the top remote monitoring and management (RMM) platforms in the industry, and supervised by Progent's certified group of information technology professionals, ProSight Network Audits help you see how closely the deployment of your core infrastructure devices adhere to best practices. The Basic and Advanced options for ProSight Network Audit services are available at a budget-friendly, one-time cost and deliver instant ROI like a more manageable Active Directory system. Both also come with one year of cutting-edge remote network monitoring and management (RMM). Advantages can include easier network management, improved compliance with information security requirements, more efficient utilization of network resources, faster problem resolution, more reliable backup and restore, and increased uptime. Read more information about ProSight Network Audits IT infrastructure assessment.

Progent's ProSight Ransomware Preparedness Report
Progent's ProSight Ransomware Preparedness Report is an affordable service based on a brief phone discussion with a Progent information assurance consultant. The interview is designed to evaluate your organization's ability to block ransomware or recover quickly after an assault by a ransomware variant such as Ryuk, WannaCry, MongoLock, or Locky. Progent will work with you personally to collect information about your existing antivirus tools and backup/recovery system, and Progent will then produce a custom Basic Security and Best Practices Report describing how you can apply industry best practices to build a cost-effective security and backup/recovery system that reduces your exposure to ransomware and aligns with your company's needs. For additional information, see Progent's ProSight Ransomware Preparedness Report Service.

Contact Progent for More Information about ProSight Email Guard Security Gateway Services
If you are interested in using Progent's ProSight Email Guard security gateway or need help with any aspect of email infrastructure or security, call 800-993-9400 or visit Contact Progent.

Glossary of Terms Related to Spam Filtering Technology

AES-256
The Advanced Encryption Standard (AES) is a cyber security specification adopted by the National Institute of Standards and Technology (NIST). AES-256 offers the highest level of encryption available within the AES family.

Allow List
Also called a whitelist, contains email addresses or domain names that are exempted from being blocked by a spam filter.

Anti-fraud Intelligence
Linguistic analysis to protect against fraudulent emails, which can take the form of spear phishing, spoofing, fee frauds or bogus offers of help.

Bayesian Analysis
A linguistic algorithm that develops profiles of the words and phrases used in legitimate email collected from specific users or organizations and determines whether new email from these sources fit their linguistic profile. Emails that are out of character have a higher likelihood of being spam.

Block List
Also called a blacklist, contains email addresses or domain names that are to be blocked by a spam filter.

Content Filtering
Most commonly refers to the ability to block or whitelist websites based on category, reputation, use of encryption, specified URL or other characteristics. In the context of ProSight Email Guard, content filtering refers to the ability to block, allow or quarantine an email message based on the results of scanning specified components of the message including subject, headers, body, attachments, sender, and recipient. (See Content Policies.)

Content Policies
Content policies allow administrators to define email filtering based on any combination of subject, headers, body, attachments, sender, or recipient. For example, specified keywords, categories or character sets can be automatically detected and blocked. Based on content policy, administrators can configure their email security gateway to block, allow or quarantine inbound or outbound email and to encrypt outbound email. Careful management of content policies can keep an organization from being blacklisted as a source of spam and other malware.

Data Leakage Protection
Often used as an alternative to data loss prevention (DLP), but can imply that compromised data retains its availability to authorized users and keeps its integrity. (See Data Loss Prevention.)

Data Loss Prevention (DLP)
Data loss prevention (DLP) for email entails scanning the content of email messages and attachments and blocking the transmission of sensitive information. DLP allows administrators to establish and enforce policies that block or encrypt outbound email that could carry inappropriate information. DLP features included in ProSight Email Guard can also help organizations avoid reputation loss and stay in compliance with industry security standards and government regulations such as HIPAA and Sarbanes-Oxley.

Delegated Administration
With ProSight Email Guard, control of domain-level settings can be assigned to the Domain Admin role, which has the most permissions, the Helpdesk role, with fewer permissions, or the Governance, Risk Management and Compliance (GRC) Account role, which has a specific role with limited permissions. The User role allows users to view and manage their own account and their quarantine inbox and related settings. Delegation significantly reduces the burden of email administration by safely offloading certain management responsibilities.

Denial of Service (DoS) Attack
An attack designed to bring down a network by flooding it with useless traffic. DDOS (Distributed Denial of Service) is an attack by multiple systems, often compromised by a Trojan, on a single system.

Directory Harvest Attack (DHA)
Scripted attempts designed to steal directory information from unprotected email servers. Spammers send messages with a generic address to your SMTP mail server. For example, spammers will try sending 'ed@acme.com,' 'sue@acme.com' or other names until the server recognizes a name and accepts a message. Spammers combine dictionaries of common names and tabulate which addresses work and which do not. The technique can yield an overwhelming number of delivery requests, consuming server processing power. Spammers then sell the compiled list of valid email addresses to other spammers, resulting in spam for new and unused accounts. False Positive
A valid email incorrectly identified as spam. Without any tuning, ProSight Email Guard has a false positive rate of 0.01 percent, one of the lowest in the industry.

Hardened Datacenter
Highly secure, fault-tolerant facilities housing IT equipment connected to telecommunications networks. The facilities accommodate web servers, email servers, switches, routers, mass storage and other critical equipment and feature redundancy, backup power, and physical security. Cloud-based infrastructure can combine multiple hardened datacenters in separate geographic regions for high availability and disaster recovery.

Heuristic Rules Analysis
A branch of artificial intelligence whereby expert systems use programs that are self-learning and improve with experience. With spam filtering, the more messages processed the better the results.

HTTPS
The use of Secure Socket Layer (SSL) or Transport Layer Security (TLS) under standard HTTP layering to provide secure web access through encryption.

Image Spam
Image spam, which at one point represented around one third of all Internet traffic, is a technique that hides text, typically a URL, by embedding it within an image. ProSight Email Guard uses an Optical Character Reader (OCR) engine to detect this threat. The Update Center also maintains Internet traps known as "honeypots" to build blacklists of image spam senders.

Intent Analysis
Multi-level analysis that recursively follows web links, email addresses and phone numbers embedded in email messages to determine whether they are associated with legitimate entities. Intent analysis also analyzes domain attributes to profile email campaigns.

Key Management
Email encryption requires the sender and recipient to exchange their encryption keys before sending or receiving protected emails. Key management is complex and includes the creation, distribution, safe storage, exchange and use of encryption keys. ProSight Email Guard's cloud-based solution for email encryption stores keys centrally and manages them automatically without burdening administrators or users.

LDAP
The Lightweight Directory Access Protocol (LDAP) is an open, industry-standard application protocol for accessing and maintaining distributed directory information services over an IP network. ProSight Email Guard's Exchange Accelerator/LDAP Verification feature uses the LDAP support built into Microsoft Exchange to protect against dictionary attacks, which attempt to break into a system by trying every word in a hacker's "dictionary" of possible passwords.

Link Protection
ProSight Email Guard's Link Protection, when activated, automatically rewrites any URL embedded within an inbound email and directs it to a safe URL before delivering the email. If the recipient clicks on the embedded URL, ProSight Email Guard evaluates the link for validity and reputation. If the domain appears to be valid, the user is directed to that website. If the URL is suspicious, the user is directed to a warning page which shows the actual link and explains why the URL was blocked.

OCR Engine
Embedding text in images is an established technique used by spammers to avoid detection by the text processing mechanisms in anti-spam engines. An optical character recognition (OCR) engine allows a spam filter to analyze the text rendered inside an image. Before submitting images to the OCR engine, ProSight Email Guard uses a variety of image processing technologies to normalize images whose text has been obfuscated with speckling, shading or color manipulation. The Update Center also uses advanced image processing algorithms to create fingerprints that can be used to block messages containing image spam.

Phishing
A scam that usually involves a fraudulent email purporting to come from a legitimate sender such as a bank and that either contains links to a spoofed website or else tries to talk the recipient into disclosing private information such as a password or social security number. ProSight Email Guard detects Phishing scams by using a specialized Bayesian database. Attacks that include information that suggests familiarity or friendship with the recipient are known as Spear Phishing and account for about 91% of email attacks.

Polymorphic Viruses
A virus that self encrypts by changing its signature to avoid detection by simple virus scanners. ProSight Email Guard relies on a supercomputing grid that uses a partial checksum approach to identify the unchanged signature portions of a virus body.

Predictive Sender Profiling
Identifying suspicious behaviors from sources who currently have clean reputations, for example newly infected bots on otherwise legitimate computers.

Quarantining
A quarantined email can be sent to an individual quarantine inbox assigned to the recipient or to a global quarantine mailbox designated by the administrator. Individuals can have quarantine accounts on the ProSight Email Guard security gateway, which takes the load off the email server, or on their regular mailbox. In this case, ProSight Email Guard alters the subject text of quarantined messages to show that the message could be spam.

Rate Control
The ability to pace inbound or outbound email from a single IP address or email address based on pre-configured frequency thresholds. Delivery of messages from sources that exceed the threshold is delayed in order to stabilize system performance.

Reputation Analysis
The use of databases that include the IP of addresses for known spammers, safe email senders, and web addresses known to be associated with spam. Email from IP addresses with poor reputations or whose content includes web addresses with poor reputations can be identified and handled according to spam policies.

Scoring Thresholds
After an email passes through the ProSight Email Guard security gateway it is given a score ranging from 1 to 10 representing the likelihood that the message is spam. The administrator can use scoring thresholds to automate how messages are managed by choosing to allow, tag, quarantine or block emails depending on their score.

Security Perimeter
The outermost edge, such as a firewall or security gateway, over which the enterprise has control over an email message before the message is received from or passed to the Internet.

Signatures
Also called a fingerprint, a series of bytes within a virus that uniquely identifies it and that can be searched for by anti-virus filters.

Spam
Unsolicited and unwanted email usually sent in bulk as part of marketing campaigns but sometimes sent with malicious intent.

Spoofing
A phishing technique whereby an attacker uses an IP address that appears to come from a trusted host. One of the most notorious examples is the exploit from service@aol.com. Spoofing attacks often include links to a fraudulent, or spoofed, web site that impersonates a familiar web site.

Spooling
A disaster recovery feature whereby incoming email is stored temporarily in the cloud or redirected in the event that your on-premises data center is disrupted. ProSight Email Guard's Cloud Protection Layer can store all your inbound email for up to four days or direct it to an alternative destination if your email server becomes unavailable. Meanwhile, Progent can provide expert online or onsite support to bring your local system back into service quickly.

Spyware
Software that collects and possibly shares information about a person without specified consent. Common forms of spyware include cookies, adware and Trojans. The collected information is typically used for marketing, but can also be used more maliciously. Major corporations (e.g., Facebook) use spyware routinely and legally. ProSight Email Guard includes technology that provides real-time protection from malicious spyware attacks.

SMTP
Short for Simple Mail Transfer Protocol, a protocol for sending email messages between servers. SMTP email servers are a common target of Directory Harvest Attacks.

Tagging
A technique for helping users to identify filtered email that meets some criteria for being spam. Tagged emails are delivered with a customized label appended to the subject field, e.g., [BULK]. This allows users to make their own determination about how to deal with them.

TLS
The Transport Layer Security (TLS) encryption protocol allows secure communication over the Internet. The ProSight Email Guard security gateway supports SMTP over TLS to encrypt email traffic between sites over the Internet.

Viruses
Computer code that can replicate itself. Viruses are commonly spread via email and allow an attacker to steal or destroy data or take control of an infected system. Types of viruses include Trojans and worms.

Zero-hour Protection
The ability to develop and distribute defenses against newly discovered spam and viruses within minutes rather than days. The hybrid infrastructure of ProSight Email Guard is designed to provide this capability.

Also See:

• ProSight Email Guard Overview
• Frequently Asked Questions about ProSight Email Guard
• ProSight Email Guard Datasheet