The document presents the nospamproxy® protection system as a modern anti-spam solution that focuses on email rejection rather than sorting, minimizing the impact of spam on productivity and storage. It highlights the high percentage of spam in email traffic, the negative effects of spam on business processes, and the customizable, self-learning features of the nospamproxy system which ensure legal compliance. Additionally, it offers integrated options for email encryption and large file exchanges, making it a scalable and resource-efficient solution for organizations.

1. Modern Anti-Spam with NoSpamProxy Protection
Rejection – No Sorting
Thomas Stensitzki

2. Introduction
Thomas Stensitzki
Principal Enterprise Consultant
Granikos GmbH & Co. KG
MCSM Messaging, MCM: Exchange 2010
MCSE, MCSA, MCITP, MCTS, MCSA, MCSA:M, MCP
E-Mail: thomas.stensitzki@granikos.eu
Web: http://www.granikos.eu
Blog: http://blog.granikos.eu

3. Spam in numbers
~88% of received messages are spam
~4% of received messages have malicious content
Postini: Only 12% of received emails are legitimate (Feb 2013)
Microsoft: 94% spam, 600 million emails a week
Trend Micro: Spam ratio varies by country
http://bit.ly/GlobalSpamMap

4. Spam ratio per country (Jan 2014 – Feb 2015)
> 80%
50% - 80%
20% - 50%
< 20%
Source: TrendMicro

5. Damage and cost
Loss in end-user productivity
Restrained mobile access to company resources
Loss of communication
Loss of network bandwidth
Waste of storage
- Mailbox databases
- Archive storage (expensive)
Example for loss of productivity:
30 spams per day = 5 minutes x 220 working days per year
2 working days per year and employee
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6. Rejection
No interruption of end-user routine
False positives easy to handle
Self learning connections and domain
trusts
No waste of mailbox database storage
No waste of archive storage
RFC compliant rejection (NDR)
Reduced administrative intervention
Sorting (classic approach)
Interuption of end-user working routine
Manual action by end-user required
Waste of mailbox database storage
Waste of archive storage
Risk of large number of unhandled spam
messages
Comparison
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7. Rejection
Delivered Blocked
Sound email OK
Spam nuisance OK
Sorting (classic approach)
Delivered Blocked
Sound email OK danger
Spam nuisance OK
Comparison
Scanning – Assessment – Rejection
Sound senders are sent a NDR
Spammers are unable to deliver
Risk of false positives is defused
- Sound senders can react on NDR
Receiving – Assessment – Processing
- Deletion, Quarantine, Marking
Depending on product
False Positives
- Danger of important information being lost without
sender and recipient knowing about it

8. Solution
NoSpamProxy® Protection – Mail Gateway
Rejection instead of sorting
- The alternative approach to spam protection
Sound emails are identified
- Self learning mechanism to identify desired connections and handling domain trusts
Customizable to business needs
- Detailed rule set of filters and actions for incoming and outgoing messages
Scalable Anti-Spam Solution
CYREN Premium Anti-Virus integrated in product
Component of Net at Work Mail Gateway

9. Legal considerations
Applicable in Germany: § 206 StGB:
„It is a criminal offence to suppress an entrusted communication“
Once an email has been received, its deletion or filtering by a third party is an
offence
- That is the primary reason why even spam must be archived
NoSpamProxy does not accept spam nor does it suppress any communication
entrusted to it
- A regular NDR is being generated
BSI*: Analogy between Spam and unsolicited advertising
*BSI: Federal Office for Information Security

10. User Interface
Multi-Role server with default rule set

11. Sound email
Concentrating on negative spam characteristics leads to false positives
Unique Level of Trust technology
Bonus points for desired email connections (sender – recipient)
System learns dynamically about desired connections
Easy authorization of external senders
- Simple send an email to the external sender to authorize incoming messages
Enables applying more stringent spam filtering rules
- Various filters and actions are available

12. In a nutshell
Acts as a SMTP proxy
Spam is identified while message is in transmission
- Connection can be aborted with a 5xx error status to the sending MTA
Installed as the first SMTP endpoint from the internet
- Next hop can be an Edge server role or an internal Hub server role
Company NetworkNoSpamProxy Protection
Multi-Role
Exchange
Server

13. Topology example 1
Internet facing servers
not domain joined
Internal server domain
joined
One gateway server
possible, but no
redundancy
1 Gateway Role
1 Intranet Role
AD
Exchange Server
Transport Role
Enterprise Network
NoSpamProxy
Intranet Role
NoSpamProxy Protection
Gateway Rolle
HTTPS

14. Topology example 2
AD
External
SMTP
servers
Exchange Server
Transport Role
Enterprise Network
NoSpamProxy
Gateway Role
Server1/2
NoSpamProxy
Intranet Role
SMTP
Web Service
Internet facing
servers not domain
joined
Internal server
domain joined
Redundant Email
Servers
N Gateway Role
1 Intranet Role

15. NoSpamProxy® Encryption (aka enQsig)
Centralized email signing and encryption at the gateway
Supports S/MIME and PGP
Centralized certificate store and cert provisioning
Qualified signatures applied to electronic invoices (INVOIC-Messages)
Password protected emails with PDF Mail
De-Mail connector and interface to Deutschland-Online Infrastruktur (DOI)
Interfaces to ECM- and other email systems

16. NoSpamProxy® Large File
Large files exchange via secure portal
Email client integration (Outlook)
Portal provided as SSL/TLS secure web server
Access password protected
No use of cloud storage

17. Summary
No loss of Information – sender is informed
No wasted working hours, no manual ploughing through quarantine
Self learning processes
Fully customizable set of rules
IT Resource saving (bandwidth, storage, maintenance)
Full legal compliance
Additional modules for email encryption and file exchange
- NoSpamProxy Encryption
- NoSpamProxy Large File

18. Questions
Email: info@granikos.eu
Web: http://www.granikos.eu
Blog: http://blog.granikos.eu
Twitter: @Granikos_DE