GFI MailSecurity operating modes 

GFI MailSecurity can be operated in 2 modes: 

1.  Exchange 2000/2003 VS API mode 

2.  SMTP gateway mode 

Depending  on  your  network  set up,  and  your  objectives  in  deploying 

GFI MailSecurity, either  mode can be applicable. In some cases you 

might consider deploying GFI MailSecurity in both modes.  

GFI MailSecurity VS API Exchange 2000/2003 mode 

If  you  have  Microsoft  Exchange  2000  or  2003,  GFI  MailSecurity  can 

integrate with Exchange Server via the Microsoft Virus Scanning API 

(VS API). 

What is and why use VS API (Virus Scanning API)? 

Exchange  2000  &  2003  provides  a  new  virus  scan  API  that  is 

implemented  at  very  low level  in  the  Exchange  store.  This  allows  a 

virus  scanning  application  to  run  with  high  performance  and 

guarantees  that  the  message  will  be  scanned  before  any  client  can 

access a message or attachment. This low level access facilitates the 

elimination of viruses such as the Melissa virus. 

In  addition,  VS  API  reduces  scalability  issues  that  can  arise  when  a 

particular  server  has  a  large  number  of  users/mailboxes.  VS API s 

real time scan allows messages and attachments to be scanned once 

before delivery, rather than multiple times determined by the number 

of  mailboxes  the  message  is  delivered  to.  This  single instance 

scanning also helps prevent messages from being rescanned when a 

message  is  copied.    GFI  MailSecurity  VS  API  has  the  following 

features: 

  Native MIME/MAPI content scanning  

  Proactive scanning  

  Priority based queuing  

  Multithreaded queue processing  

  Per Messaging Database configuration options  

  Enhanced background scanning  

  Event logging  

  Virus scanning API specific Performance Monitor counters  

Why choose a product based on the VSAPI?  

Microsoft  strongly  encourages  the  development  and  adoption  of 

Exchange VS API based anti virus solutions 

  VS  API  is  secure  and  preserves  the  integrity  of  the  Information 

Store and its databases 

  The  Microsoft  Exchange  product  group  is  committed  to  providing 

enhancements to this API, bug fixes, documentation, and technical 

assistance to ISVs using VS API (as appropriate) 

Explaining GFI MailSecurity 

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