Allowing remote agents (VPN) to make/receive external calls from PSTN

[synthesis]

Hello. I am working at an organization which receives calls from customers on the Public Switched Network (PSTN), which is routed to the Mitel 3300 ICP and answered by one of the available agents. There are remote agents at a branch of the organization which require to make/receive external calls via the 3300 ICP.

I am working on a plan to allow the remote agents using the Mitel 5312 IP phones to connect to the Mitel 3300 ICP via a VPN. The aim is for these remote agents to be able to receive external calls which are made by customers on the PSTN. These calls from the PSTN are routed to the 3300 ICP at the main site.

The topology is as follows:

remote agents <--> VPN <--> INTERNET <--> VPN <--> 3300 ICP <---> PSTN <--> caller (customer)
                                                                                                 |
                                                                                                 |
                                                                                                 v
                                                                                 local agents (main site)


With regards to bandwidth, QoS etc would this setup be feasible for a remote agent to make/receive calls from callers on the PSTN? (The main site and branch are located within the same city).

[acejavelin]

So basically you have a VPN from the remote site to the host site, assuming simple networking issues like VLAN are not an issue or at least taken into consideration with routing, this is actually quite common and normal... We see it over VPNs, MPLS circuits, T-1's, and other dedicated connections. Just remember to have sufficient bandwidth and quality of connection and your good to go. A PC/client based VPN will NOT work though, this needs to be a hardware based solution, router to router being the most common.


The whole problem with remote phone on the 3300 is NAT since the 3300 does not support it directly. A VPN doesn't use NAT for the traffic between nodes across the VPN tunnel, so the phones will work fine.

[x-man]

Would not teleworker be better or as least as good and the MBG takes care of security. And no need to maintain a VPN tunnel.

[acejavelin]

Would not teleworker be better or as least as good and the MBG takes care of security. And no need to maintain a VPN tunnel.

True... MiVoice Border Gateway is specifically designed for this application, it would easily handle this application quite well. I didn't suggest it because the OP asked about a VPN solution directly.

Security wise, I think if properly implemented neither solution is superior to the other.