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As noted above, SIP ALG is just one piece of the larger whole that is your home network. If disabling SIP ALG does not help resolve problems with your NocTel handset set up at home, a strong next step to resolution is to contact your Internet Service Provider and inquire if they allow the common ports used for VoIP or have possibly had any changes to allowing VoIP traffic. (List of ports used by NocTel - Polycom-based)

Small and Medium Business Combo Modems

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