A Retrospective on Future Anti-Spam Standards Internet Society of China Beijing – September, 2004 Dave Crocker Brandenburg InternetWorking < Internet Society of China Beijing – September, 2004 Dave Crocker Brandenburg InternetWorking <
2 2 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 Retrospective on the Future Spam is complex, confusing and emotional Imagine that time has passed What changes will be important? Will it still be easy to reach everyone? Will it be cumbersome, with fragmented communities? Spam Legitimate business will behave acceptably (mostly) Rogue (criminal) spammers will be worse than today Spam is complex, confusing and emotional Imagine that time has passed What changes will be important? Will it still be easy to reach everyone? Will it be cumbersome, with fragmented communities? Spam Legitimate business will behave acceptably (mostly) Rogue (criminal) spammers will be worse than today
3 3 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 Security Functions TermFunction Identification Who does this purport to be? Authentication Is it really them? Authorization What are they allowed to do? Accreditation What do I think of the agency giving them that permission?
4 4 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 What Will Be Standard? Accountability (Author & Operator) Authentication Authorization Reputation Filtering Format of rules Accountability (Author & Operator) Authentication Authorization Reputation Filtering Format of rules Reporting & monitoring Immediate problems Aggregate statistics Enforcement (Contracts and laws are standards) Terminology Acceptable behavior
5 5 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember Path(s) Today! MUA MSAMTA MDA MUA MTA Peer MTA MTA MDA MUA Mail Agents MUA = User MSA = Submission MTA= Transfer MDA= Delivery
6 6 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 SPF and Sender-ID: Author Path Registration oMUAMSA MTA 1 MTA 4 MDArMUA MTA 3 MTA 2 Peer MTA Assigns Sender & MailFrom Did MSA authorize MTA 1 to send this message ? Did MSA authorize MTA 2 to send this message ? Did MSA authorize MTA 3 to send this message ? 1.Authority and Accreditation of MSA and MSA domain administrators 2.MSA must pre- register and trust each MTA in path
7 7 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 My Personal Favorites Validate content DomainKeys Public key signature of the message Validate operator CSV Operator validates MTA [Validate MailFrom] [BATV] Validate content DomainKeys Public key signature of the message Validate operator CSV Operator validates MTA [Validate MailFrom] [BATV] Reputation CSA & DNA (CSV) Reporting No candidates, yet Enforcement We are still learning
8 8 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 Client SMTP Validation: Assess Peer MTA MUAMSAMTA MTAMDAMUA MTA MTA Peer MTA Does a domain's operator authorize this MTA to be sending ? Do independent accreditation services consider that domain's policies and practices sufficient for controlling abuse?
9 9 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 CSV Functions TermFunctions Identification Client SMTP HELO domain name Authentication Domain name lists IP Address Authorization Name is authorized to be MTA Accreditation Name may point to accreditors Accreditors may list domains
10 D. Crocker, Brandenburg InternetWorkingISOC China – Beijing,Saeptember 2004 How to Choose the Future Look at each choice Who must adopt it? When? How much effort is need to administer it? How much does it change ? Look at each choice Who must adopt it? When? How much effort is need to administer it? How much does it change ? Xie Xie