This is because the Polycom doesn't support STUN, RPORT or any other nat traversal technology.  You have a couple of choices please review http://wiki.freeswitch.org/wiki/NAT_Traversal

Also review the NDLB-force-rport option for the sofia profile to assume rport.  CAUTION this breaks things like cisco phones.

/b

On Apr 8, 2009, at 9:02 PM, zhaoxxqq wrote:

hi,
I use FS server at public Address. I use polycom's IP550 at private address(192.168.0.120), Now there is a problem that the IP550 can not register to FS. But when I use account to eyebeam, the registering is OK. the attachment is my IP 550's config file, I think it must be NAT problem. Can anyone can help me solve it? 

Brian West
brian@freeswitch.org

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