You are the only person who has mentioned reverse DNS lookups.
However, it is true that you do in fact need to already know the identity of the sending MTA/MSA before you can do a "reverse DNS lookup". What does this have to do with the price of tea in China? And what value do you think a reverse DNS lookup adds to the identity information you already (obviously) have? -- The fact that there's a Highway to Hell but only a Stairway to Heaven says a lot about anticipated traffic volume. >-----Original Message----- >From: Michael Thomas [mailto:m...@fresheez.com] On Behalf Of Michael >Thomas >Sent: Monday, 8 July, 2019 19:12 >To: Keith Medcalf; nanog@nanog.org >Subject: Re: SHAKEN/STIR Robocall Summit - July 11 2019 at FCC > >Jon Callas, Eric Allman, the IETF security geek contingent and even >me >disagree with you. rfc 4871 disagrees with you. STD 76 disagrees with >you. Trillions of signed messages disagree with you. Steve Bellovin >probably disagrees with you too since you seem to be under the >illusion >that a reverse DNS lookup tells you anything useful. > >::eyeroll:: > >Mike > >On 7/8/19 6:06 PM, Keith Medcalf wrote: >> Wow! >> >> You must not know much about networking or programming if you do >not know how to ask the OS to tell you the address/port associated >with the "other end" of a TCP connection. Obviously you know who is >sending the message since they are in bidirectional communication >with you at the time you are receiving the message, and you need to >know where to send the "carry on James" prompts to get them to send >more data... >> >> Therefore you always know who submitted a message. >>
