pmg-intro.adoc

   1 Introduction
   2 ============
   3
   4 What is {pmg}?
   5 --------------
   6
   7 E-mail security begins at the gateway by controlling all incoming and
   8 outgoing e-mail messages. {pmg} addresses the full spectrum of
   9 unwanted e-mail traffic, focusing spam and virus detection. {pmg}
  10 provides a powerful and affordable server solution to eliminate spam,
  11 viruses and blocking undesirable content from your e-mail system. All
  12 products are self-installing and can be used without deep knowledge of
  13 Linux.
  14
  15 image::images/Proxmox_Mail_Gateway_Mailprocessing_final_1024.png[]
  16
  17 Features
  18 --------
  19
  20 Spam detection
  21 ~~~~~~~~~~~~~~
  22
  23 {pmg} uses a wide variety of local and network tests to identify spam
  24 mail. Here is a short list of used filtering methods:
  25
  26 Receiver Verification::
  27
  28 Many of the junk messages reaching your network are emails to
  29 non-existent users. {pmg} detects these emails on SMTP
  30 level, which means before they are transferred to your networks. This
  31 reduces the traffic to be analyzed for spam and viruses up to 90% and
  32 reduces the working load on your mail servers and scanners.
  33
  34 Sender policy framework (SPF)::
  35
  36 Sender Policy Framework (SPF) is an open standard for validating
  37 emails and to prevent sender IP address forgery. SPF allows the
  38 administrator of an Internet domain to specify which computers are
  39 authorized to send emails with a given domain by creating a specific
  40 SPF record in the Domain Name System (DNS).
  41
  42 DNS-based Blackhole List::
  43
  44 A DNS-based Blackhole List (DNSBL) is a means by which an Internet
  45 site may publish a list of IP addresses, in a format which can be
  46 easily queried by computer programs on the internet. The technology is
  47 built on top of the Domain Name System. DNSBLs are used to publish
  48 lists of addresses linked to spamming.
  49
  50 SMTP Whitelist::
  51
  52 Exclude senders from SMTP blocking. To prevent all SMTP checks
  53 (Greylisting, Receiver Verification, SPF and RBL) and accept all
  54 e-mails for the analysis in the filter rule system, you can add the
  55 following to this list: Domains (Sender/Receiver), Mail address
  56 (Sender/Receiver), Regular Expression (Sender/Receiver), IP address
  57 (Sender), IP network (Sender)
  58
  59 Bayesian Filter - Automatically trained statistical filters::
  60
  61 Some particular words have a higher probability of occurring in spam
  62 emails rather than in legitimate emails. By being trained to
  63 recognize those words, the Bayesian checks every email and adjusts the
  64 probabilities of it being a spam word or not in its database. This is
  65 done automatically.
  66
  67 Black- and Whitelists::
  68
  69 Black- and Whitelists are an access control mechanism to accept,
  70 block, or quarantine emails to recipients. This allows you to tune the
  71 rule-system by applying different objects like domains, email address,
  72 regular expression, IP Network, LDAP Group, and others.
  73
  74 Autolearning algorithm::
  75
  76 {pmg} gathers statistical information about spam
  77 emails. This information is used by an autolearning algorithm, so the
  78 system becomes smarter over time.
  79
  80 Spam Uri Realtime BlockList (SURBL)::
  81
  82 SURBLs are used to detect spam based on message body URIs (usually web
  83 sites). This makes them different from most other Real-time
  84 Blocklists, because SURBLs are not used to block spam senders. SURBLs
  85 allow you to block messages that have spam hosts which are mentioned
  86 in message bodies.
  87
  88 Greylisting::
  89
  90 Greylisting an email from a sender your system does not recognize,
  91 means, that it will be temporarily rejected. Since temporary failures
  92 are built into the RFC specifications for mail delivery, a legitimate
  93 server will try to resend the email later on. This is an effective
  94 method because spammers do not queue and reattempt mail delivery as is
  95 normal for a regular Mail Transport Agent.
  96 +
  97 Greylisting can reduce e-mail traffic up to 50%. A greylisted email
  98 never reaches your mail server and thus your mail server will not send
  99 useless "Non Delivery Reports" to spammers.
 100
 101 SMTP Protocol Tests::
 102
 103 {postfix} is able to do some sophisticated SMTP protocol tests (see
 104 `man postscreen`). Most spam is sent out by zombies (malware on
 105 compromised end-user computers), and those zombies often try to
 106 maximize the amount of mails delivered. In order to do that, many of
 107 them violates the SMTP protocol specification and can thus be detected
 108 by these tests.
 109
 110
 111 Virus detection
 112 ~~~~~~~~~~~~~~~
 113
 114 {pmg} integrates {clamav}, which is an open-source (GPL) antivirus
 115 engine designed for detecting Trojans, viruses, malware and other
 116 malicious threats.
 117
 118 It provides a high performance mutli-threaded scanning daemon, command
 119 line utilities for on demand file scanning, and an intelligent tool
 120 for automatic signature updates.
 121
 122
 123 Object-Oriented Rule System
 124 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 125
 126 The object-oriented rule system enables custom rules for your
 127 domains. It’s an easy but very powerful way to define filter rules by
 128 user, domains, time frame, content type and resulting action. {pmg}
 129 offers a lot of powerful objects to configure your own custom system.
 130
 131 WHO - objects::
 132
 133 Who is the sender or receiver of the e-mail?
 134
 135 WHAT - objects::
 136
 137 What is in the e-mail?
 138
 139 WHEN - objects::
 140
 141 When is the e-mail received by {pmg}?
 142
 143 ACTIONS - objects::
 144
 145 Defines the final actions.
 146
 147 Every rule has five categories FROM, TO, WHEN, WHAT and ACTION. Every
 148 of these categories can contain several objects and a direction (in,
 149 out or both).
 150
 151 Options range from simple spam and virus filter setups to
 152 sophisticated, highly customized configurations blocking certain types
 153 of e-mails and generating notifications.
 154
 155
 156 Spam Quarantine
 157 ~~~~~~~~~~~~~~~
 158
 159 Identified Spam mails can be stored to the user accessible Spam
 160 quarantine. Thus users can view and manage there Spam mails by
 161 themselves.
 162
 163
 164 Tracking and Logging
 165 ~~~~~~~~~~~~~~~~~~~~
 166
 167 The innovative Proxmox Message Tracking Center tracks and summarizes
 168 all available logs. With the web-based and user friendly management
 169 interface, the IT admins can easily overview and control all
 170 functions from a single screen.
 171
 172 The Message Tracking Center is very fast and powerful, tested on {pmg}
 173 sites processing over a million emails per day. All different log
 174 files from the last 7 days can be queried and the results are
 175 summarized by an intelligent algorithm.
 176
 177 - Arrival of the email
 178 - Proxmox filtering processing with results
 179 - Internal queue to your email server
 180 - Status of final delivery
 181
 182
 183 High Availability with Proxmox HA Cluster
 184 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 185
 186 To provide a 100% secure email system for your business, we developed
 187 Proxmox High Availability (HA) Cluster. The Proxmox HA Cluster uses a
 188 unique application level clustering scheme, which provides extremely
 189 good performance. Fast set-up within minutes and a simple, intuitive
 190 management keep resource needs low. After temporary failures, nodes
 191 automatically reintegrate without any operator interaction.
 192
 193 LDAP integration
 194 ~~~~~~~~~~~~~~~~
 195
 196 It is possible to query user and group data from LDAP servers. This
 197 may be used to build special filter rules, or just to provide
 198 authentication services for the Spam quarantine GUI.
 199
 200
 201 Fetchmail integration
 202 ~~~~~~~~~~~~~~~~~~~~~
 203
 204 {pmg} allows you to fetch mail from other IMAP or POP3 servers.
 205
 206
 207 Flexible User Management
 208 ~~~~~~~~~~~~~~~~~~~~~~~~
 209
 210 The administration interface uses a role based access control scheme,
 211 using the following roles:
 212
 213 Superuser::
 214
 215 This role is allowed to do everything (reserved for user 'root').
 216
 217 Administrator::
 218
 219 Full access to mail filter setup, but not allowed to change network setup.
 220
 221 Quarantine Manager::
 222
 223 Is able to view and manage the Spam Quarantine.
 224
 225 Auditor::
 226
 227 Has read-only access to the whole configuration, can access logs and
 228 view statistics.
 229
 230
 231 Your benefit with {pmg}
 232 -----------------------
 233
 234 * Open source software
 235 * No vendor lock-in
 236 * Linux kernel
 237 * Fast installation and easy-to-use
 238 * Web-based management interface
 239 * REST API
 240 * Huge active community
 241 * Low administration costs and simple deployment
 242
 243
 244 include::getting-help.adoc[]