You will need to implement IPSec tunnels between your sites
With IPSec the communication and security are guaranteed, encrypted traffic site to site
Do you need to interconnect just voip packets ?
Do you have a Router/Firewall in these sites ? like Mikrotik, Fortigate, Cisco ...
With out doub, IPSec tunnels its your solution, i can implement it in your network
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More than 4 years working as a network specialist
Resolution of problems of any level
Designed and set up large networks in hotels, shopping centers, businesses, etc.
Management of IPSec VPN servers, routing & switching, hotspots, load balances, Firewalls, BGP, MPLs
Management and total control in manufacturers such as Mikrotik, Fortinet, Clavister, Ubiquiti, Ruckus, Mojo, CISCO, Sophos, HP, Netgear