1
ECC certificates
Question asked by Nick Jansen - 11/25/2024 at 10:34 AM
Answered
Has anyone used an ECC certificate on their SmarterMail server for SMTP communication? Have you noticed any issues with other SMTP servers your server communicates with not understanding them? Will SmarterMail even let me use one? Can they even be used for SMTP at all? I've been using them on web servers for a long time, but I don't know how common ECC support is on other SMTP servers my SmarterMail server might communicate with. I'd feel comfortable using one for webmail, but I don't know about SMTP.

My current RSA certificate works fine, and there's not really a pressing reason to switch other than I'm about to renew it and have the choice. It's more of a curiosity at this point. The smaller key size used in ECC certificates is nice though. I have a small enough user base that I could probably test it for a while and see if me or my users end up not receiving messages they're expecting or if related errors appear in my logs.

3 Replies

Reply to Thread
1
k Replied
ecc cert works in our test sm server. (but very low traffic). can send/receive mail to/from internet.
1
Steve Norton Replied
Marked As Answer
I did use an ECC certificate for a while but found out that some sending mail servers (pphosted.com are an example) have hardened their cipher suites to match their own RSA certificate deployment and removed all suites that support ECC. The result is negotiation failure and email falling back to clear text, not great so I'm back on RSA for now.
0
Nick Jansen Replied
OK cool, thank you both for the details. Seems like it's probably safer to stick with RSA for now.

Reply to Thread