Would like to do a longer post on what I have learned about IP telephony, but in the meantime just fixed a problem setting a new phone (Polycom SP335) up at the office and have to say I continue to be impressed by our phone system provider, OnSIP. Never have to wait long to speak to a real person, no ridiculous prompts to navigate, and very capable and patient technical support. I was having a problem getting this phone registered with our provider, they were able to look at what was going on remotely, identified the router as the likely culprit, and steered me to a setting that needed to be changed, in WAN Setup, NAT Filtering, I had to check the Disable SIP ALG and the radio button for Open (instead of Secured). I might have figured that out eventually, but thanks to OnSIP I didn’t have to!