mitel interconection doubt

[Sejoita]

Hi all!
Im new on a mitel´s world.
i adquired 2 mitels cx2 and interconnect 2 aastra bp with trunk sip with the Mitels and the mitel with aastra with bri trunks in my lan and we can call between aastras withouth problems.
i want connect now the 2 mitels with the sip trunk in the public network.I readed that sip trunks have problems with the nat tables and redirections of the packets.Its really true?
Could be possible with a 2 sip gateway?
what would be the recomended model for interconect 2 mitels in public network(internet)?

thnx all.

 

[slapin]

here is the problem. Actual voice path will be different then your signaling path. You need to have IP transport for both. If you know exactly how it is traveling in your particular network and can deliver it from one device to another, then sky is the limit.

 

[Sejoita]

with vpnrouters on internet works.
could work withoth vpn?