I believe that such comparison is very relative and cannot conclude the advantage of one solution over the other. Overall Quintum and Cisco products can serve absolutely the same purpose, depending on the budget and expectations. Below are several of my comments to some points from the document:
1. The number of simultaneous calls on Quintum are known because the call volume is limited by a software license. Cisco basically allows the administrator to sacrifice call volume for call quality by choosing different codecs. This is great!
2. I consider the ability of loading a different IOS on Cisco at any point of time another great advantage over any gateway vendor out there. Regarding version stability, just for the record, 12.1.(5) T8 has been rock-solid for years.
6. The debug output from Cisco is much more detailed, which I consider another great advantage.
8. When reading point 8, I came across the following question: if the E1/T1 span to the PBX side is down, how will the user from the PSTN side ever reach an extension on the PBX side “thus ensuring a transparently passage of the traffic between the PBX and the PSTN”? I believe that the previously mentioned “unique “relay bypass” functionality is actually widely implemented in the industry. For example, Cisco can be configured for route failover on span level depending on the return code from the ISDN (suppose the T1/E1 line is up and there is a protocol error of some type). However, if the D-channel of the span is down due to either a physical or signaling reason, then the gateway will not route the call out via that span at all. Another way to achieve failover either on IP or PSTN calls on Cisco is via back-to-back configuration on the spans. Furthermore, there are other solutions out there that provide even more intelligent route failover solutions for transparent call failover. What about channel failover?