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CAS mailflow

rjbarlow

Hello all,
when an e-mail reaches a CAS, the CAS lookups in AD searching for the internal recipient, I read that somewhere and I take it for sure so.
But, AFTER, the CAS delivers the e-mail directly to the destination Mailbox Server or prior delivers it to an Hub?
For what I remember to have understood ther's a direct connection CAS to MB, but I think, for example, transport rules do not affect that message, unless the server is an HUB+CAS.
Help clarifying please.

rj

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Comments

HeroPsycho

All email flows through a hub transport server, even if you were to email yourself. There's no exceptions. This allows message policies to be applied to all messages.

rjbarlow

HeroPsycho wrote: »

All email flows through a hub transport server, even if you were to email yourself. There's no exceptions. This allows message policies to be applied to all messages.

Hi HeroPsycho,
thanks much for the explanation, it is that communication (CAS -> HUB) RPC/encrypted as I could expect or by other protocol? I cannot find anything speaking about it, that is very strange seeing the crucial topic.

royal

CAS doesn't talk to HUB. HUB talks to other roles such as UM (when UM wants to submit a voicemail using SMTP to a mailbox), Mailbox (when the HUB Store Driver pulls data from Mailbox), other HUBs (when it needs to route to other sites), or Edge Servers (when HUB needs to send mail outbound and vice versa).

This is what you're looking for to see what path's are encrypted and how:
Data Path Security Reference: Exchange 2007 Help