Parallel manner – all telephones ring concurrently after one phone solutions, the rest of the phones can easily area new phone calls he GXP1600 number of IP phones are developed especially for compact organization https://maeiivz428591.isblog.net/the-grandstream-dubai-grandstream-grandstream-africa-grandstream-phones-ip-pbx-ip-phone-gsm-gateway-diaries-46452822