SIP and RTP are a pain. Long "fixed" but still a pain. ftp still refuses to die and is a pain in active mode. There are others.
Only yesterday I had to wheel out Wireshark to prove to a telephony services provider that their bod had forgotten to update a PBX with its changed WAN address.
Only yesterday I had to wheel out Wireshark to prove to a telephony services provider that their bod had forgotten to update a PBX with its changed WAN address.