Restrict access to a single client device

[Marc Patermann]

Ram schrieb (01.02.2013 10:01 Uhr):
> On 02/01/2013 01:20 AM, Dale J Chatham wrote:
>> You use SMTP authentication through postfix or sendmail.  Google [ mail
>> authentication relay   ] and you should find lots of howtos.
>>
>> I'm setting it up to use a sasldb to authenticate external users in
>> order to keep them apart from UNIX users.  Be very certain that you use
>> STARTTLS or some form of authentication for email.  Also, if you're
>> allowing internet access to e-mail, you'll want to use imaps or https.
> The idea is that end users configure their email  on Desktop, Laptop , 
> Phone , tablet, Ipad ... ( The list is getting longer every day )
> So copies of the mail are floating everywhere.
> 
> This raises a security concern
> 
> I cant block access totally from outside.
> Employees should be allowed access from outside office , but only from 
> the designated Laptop.
> One way would be to ask everyone to VPN to the office for mails , Is 
> there anyway else.
TLS client authentication with certificates?

Marc