IF you have multiple VLANs at your site - or tunnels that go somewhere other than SIG - the MX can provide protection related to those flows that never hit SIG. You need tunnels to SIG (or some other central breakout) because of the apparent need to use a common source IP. I would certainly be pushing your SaaS providers as to why they still insist on this though, TBH. But - by funnelling everything through SIG, you also get a more common approach to security, all managed in one place and applied 'near you' (your Cisco DC, wherever you are). Cloud security such as SIG also offers greater scalability than a small appliance - particularly useful for intensive processes, such as TLS decryption. You might also want to progress on from SIG to Cisco Secure Connect, which is effectively SIG in the Meraki Dashboard, but with added capability for centralised secure remote access also using that common policy - no need to choose any particular MX to point AnyConnect client at...
... View more