We have installed serveral VoIP solutions and we use IP Telephony in house as well. Our implementations use the following gateways: VG200, DT24+ and 3640's with both T1/PRI and FX cards.
There have not been any voice quality concerns. Just remember when implementing VoIP or IP Telephony, if your LAN or WAN is in bad shape quality calls may be an issue. That is why you use QoS and size WAN links, assuming you are doing toll bypass, correctly.
We have done several IP Telephony solutions and the PSTN gateways are the least of the quality issues. Most often it is WAN links that are not setup correctly or over subscribed. If the LAN calls are good, the PSTN calls will be good. You might have to tweek the db settings sometimes but more often than not you won't.
Here at Cisco we are using Cisco CallManager & IP Phones almost exclusively, and it works wonderfully. The connection to the PSTN is the easiest and by far the LEAST troublesome connection you'll need to worry about.
Where QoS comes into play most is when you are passing voice traffic over a WAN link for toll bypass or inter-office calling. We use this for our all our remote sales offices. Whenever the same WAN link is passing both voice and data QoS is paramount.
The short answer is that you don't.... That isn't entirely true while at
the same time it kind of is, but for the most part you don't configure
the softkeys. You enable or disable them via TCL. Here is the long
answer. Be sure to read the whole thing or e...
Topology: IP Phone > Switches > Microsoft NPS setup to forward 802.1x
proxy to > ISE 2.1 patch 3 Authentication: EAP-TLS using Cisco MIC SANs
Phone Models 802.1X support? 802.1x flavor Addtl Comment EAP-MD5 EAP-TLS
Cisco 3905 Y Y N Cisco 6911 Y Y N Cisco ...
This document describe how DST changes and how time changes are
implemented in DST. Daylight Saving Time (DST) is the practice of
setting the clocks forward 1 hour from standard time during the summer
months, and back again in the fall, in order to make b...