[asterisk-users] cisco phones getting SIP 401 unauthorized

[Jerry Geis]

I have a handful of cisco phones that has been working.
Today they started showing X's. looking at sip debug I see the 401 
unauthorized.

SIP/2.0 401 Unauthorized
Via: SIP/2.0/UDP IP:52110;branch=z9hG4bK29694d4a;received=IP
From: <sip:304 at IP;user=phone>
To: <sip:304 at IP;user=phone>;tag=as3155786a
Call-ID: 000ff7c0-3fd70002-23a6b16f-6c9237da at 192.168.3.99
CSeq: 101 REGISTER
User-Agent: Asterisk PBX
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY
WWW-Authenticate: Digest algorithm=MD5, realm="asterisk", nonce="03362846"


Any idea what happened? Or how to get pasted the 401?

Jerry