Shohamshalom, You need to apply a Normalization Script on the SIP Trunk which will modify the SIP Header and change ANONYMOUS / NONE / NULL to a "Replacement Number" which will be routable by CUCM.  Please find the SIP Trunk Normalization Script details below. Name: Allow-Anonymous-Calls Description:ALLOW ANONYMOUS / NONE / NULL INBOUND CALLS - Change the SIP invite from sip:Anonymous to sip:0 so that calls match the inbound call filter list Conetent: M={} --change to trace.enable() to have trace output in SDI trace.disable()   function M.inbound_INVITE(msg)  --capture inbound INVITE messages    --set the string to replace the anonymous, unavailable or restricted strings in the INVITE message    replacementNumber = "sip\:0"    trace.format("Replacement Number: %s", replacementNumber)    --Set the header values to inspect for anonymous caller    local fields = { "From" , "Remote-Party-ID" , "P-Preferred-Identity", "P-Asserted-Identity" }    local numberOfFields = #fields    trace.format("Fields/Count: %s, %s, %s, %s, %s", fields[1], fields[2], fields[3], fields[4], numberOfFields)        --loop though the header fields to inspect and replace any instance of 'anonymous' with the specified replacement number    local x = 1    while  x <= numberOfFields do       --get the field from the header       local header = msg:getHeader(fields[x])       if header == nil       then          trace.format("Field %s not found", fields[x])       else          trace.format("Field %s: %s", fields[x], header)          --does the from contain anonymous          if string.find(string.lower(header), "sip\:anonymous")            then             trace.format("Found string anonymous in %s", fields[x])             trace.format("Header: %s %s", fields[x], string.lower(header))             --replace the word anonymous with the user defined replacement number            local newHeader = string.gsub(string.lower(header), "sip\:anonymous", replacementNumber)            trace.format("New %s Field: %s", fields[x], newHeader)            --modify the From field            msg:modifyHeader(fields[x], newHeader)              else if string.find(string.lower(header), "sip\:unavailable")          then             trace.format("Found string unavailable in %s", fields[x])             trace.format("Header: %s %s", fields[x], string.lower(header))             --replace the word unavailable with the user defined replacement numbe            local newHeader = string.gsub(string.lower(header), "sip\:unavailable", replacementNumber)            trace.format("New %s Field: %s", fields[x], newHeader)            --modify the From field            msg:modifyHeader(fields[x], newHeader)              else if string.find(string.lower(header), "sip\:restricted")          then             trace.format("Found string unavailable in %s", fields[x])             trace.format("Header: %s %s", fields[x], string.lower(header))             --replace the word unavailable with the user defined replacement number            local newHeader = string.gsub(string.lower(header), "sip\:restricted", replacementNumber)            trace.format("New %s Field: %s", fields[x], newHeader)            --modify the From field            msg:modifyHeader(fields[x], newHeader)                           else             trace.format("Field %s number valid.  No change made.", fields[x])           end           end           end         end     x = x+1    end end return M   Script Execution Error Recovery Action : Message Rollback Only System Resource Error Recovery Action:   Disable Script Memory Threshold: 50 LUA Instruction Threshold: 1500     Once creating the SIP Normalization Script in CUCM under Device > Device Settings > SIP Normalization Script, apply the script to the SIP Trunk after hours.  Ensure to Apply Config & Reset the SIP Trunk (NOTE: This will drop active calls).  I have tested this in multiple deployments and verified it works.   Regards,   Dalton Woolsey ... View more