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Forum Discussion

_Mo__2's avatar
_Mo__2
Icon for Nimbostratus rankNimbostratus
Sep 26, 2018

IMAP(s) with SSL Offloading with Client Certificate Authentication

Hi,   I would like to know if it is possible to put in place a VS on the port 993 + SSL Client Profile with Require enable to force the email client to provide a client certificate.   When the ...
LTM
security
youssef1's avatar
youssef1
Icon for Cumulonimbus rankCumulonimbus
Sep 26, 2018

Hi,

As you know IMAP is an application layer Internet Protocol using the underlying transport layer protocols to establish host-to-host communication services for applications. This allows the use of a remote mail server. The well-known port address for IMAP is 143.

So in fact IMAPS (IMAP over SSL) allows IMAP traffic travel over a secure socket to a secure port, typically TCP port 993.

Internet IMAP port 993 SSL <> F5 Load balancer + Cert auth <> Exchange port 143

But I think that the problem will come from App client (messaging app) that can't negociate auth using a cert.

it's like the exchange client using OutlookAnywhere. cert auth was not possible in spite of the ssl / tls...

the best way is to test but I do not believe in this type of deployment

hope it's clear. regards,