I have a location with 10 HiperDSPs(T1), a 64MB HiperARC, a 16MB NMC and two 70s. We don't seem to have any problems running this way, but we don't do any extra routing or tunnels with the ARC. If you are wanting to utilize OSPF or anything I would suggest you put in a HiperARC with 128MB. But we have had success with the following code versions. HiperDSP 2.1.9 HiperARC 4.2.32 upgrade to 5.0.9 for TCS 4.0 NMC 7.1.8 I'm not sure about your speed question... SNMP access is much better if you upgrade to the NMC333 and the newest ARC but I'm not sure that alone makes it worth it. If you would only be upgrading to hiperARC128 and HiperNMC, it's unlikely you would see much improvement, but you would open your ability to upgrade to TCS 4.3 and with dual 130s up to TCS4.7 As far as call handling goes, I've not noticed a problem using the older Cardsets. With a non-HiperNMC you are limited to TCS 4.0, so keep that in mind when you think of V.92 :) -- Adam Barnhill Support Engineer, TotallyFabricated.com Information Technology Engineer, Poplar Bluff Internet, Inc. / Semo.net P.O. Box 190 | Poplar Bluff, MO 63902 | 573.686.9114, <http://www.semo.net/> Home of TotallyFabricated.com the creators of Total Scrutinizer