SIP ALG Problems

[TK_Liew]

Please find the forum thread below. This is related to the ISP. Look like you are having the same problem.

Idiot ISP port blocking fix

After spending days trying to figure out why one of my PEPwave MAX-BR-1 units would always have one IP phone not able to register, I finally figured out that it is the ISP blocking or consuming traffic to port 1025 Situation: PEPwave running the PPOE, so public IP is on it. Behind the PEPwave are five Yealink IP phones. They are registering to a softswitch cluster on a public IP in our data center. We are not using VPN. Same setup at many other locations with no issues. Problem at this lo…