The Edgemarc is the router you want. I have a 4500T4 and it works great with both my MGCP and SIP clients. Edgemarc is an ALG (Application Layer Gateway) which allows for premise based nat traversal. It is also a traffic shaper, it has knowledge of the VoIP devices registered on the LAN and can dynamically shape traffic by faking out TCP ACKs to allow Bandwidth for your VoIP devices. The only other option I know of for "reserving" bandwidth is to employ a rate-limit policy on an enterprise class router that uses source/destination to rate limit traffic.
The Edgemarc is the router you want. I have a 4500T4 and it works great with both my MGCP and SIP clients. Edgemarc is an ALG (Application Layer Gateway) which allows for premise based nat traversal. It is also a traffic shaper, it has knowledge of the VoIP devices registered on the LAN and can dynamically shape traffic by faking out TCP ACKs to allow Bandwidth for your VoIP devices. The only other option I know of for "reserving" bandwidth is to employ a rate-limit policy on an enterprise class router that uses source/destination to rate limit traffic.