ietf-asrg
[Top] [All Lists]

Re: [Asrg] Round one modifications to DNSBL BCP draft.

2008-04-01 10:58:48

On Mar 31, 2008, at 4:22 PM, Seth wrote:

Douglas Otis <dotis(_at_)mail-abuse(_dot_)org> wrote:
On Mar 31, 2008, at 11:44 AM, Seth wrote:
Douglas Otis <dotis(_at_)mail-abuse(_dot_)org> wrote:

Will information be added related to warnings regarding network  
provider associated address space about to be list?

I hope not.

Why do you keep assuming that only things that _have_ network  
providers can be listed?  Who is the "network provider" for a  
"Mailer-agent" header DNSBL?

Any IP address used by bad actors for sending UCEs or other types  
of abuse is being routed by a network provider.

Which network provider would you recommend notifying about an entry  
that says "X-Mailer: CloakedSender" is a spam indication?

Most black-hole/block lists are based upon the IP address where the  
octets are in reverse order.  The network provider can be noted by who  
advertised the address space.

See:
http://www.team-cymru.org

This technique depends upon ASNs observed in BGP announcements.  This  
information is often processed with a program like zebra, for example.

Some might be based upon domain names used in abuse, but a necessity  
to inform the owner of the domain is less, but could be done using  
abuse@<example.com>.

Determining the network provider helps establish their reputation,  
which should represent a significant factor in whether their  
advertised space can be trusted.  It will become apparent by a high  
percentage of their addresses abusing the network, the network provide  
does not have or enforce AUPs prohibiting abuse.  A draft about best  
practices should include a section on this topic.  This allows  
notifying the network provider to allow them to pass on timely  
information to owners of likely compromised systems.

If you want to notify the providers for the emitters of all the spam  
you get, feel free.  But you aren't going to get others to believe  
that doing so is a requirement on them.

Defining a function essential for creating a warning when a system  
becomes compromised, but may not normally be sending email is not  
required.  Not implementing this function could not be defined as a  
best practice either.

In addition, the network provider is in the unique position of  
being able to curtail the abuse immediately.

Tell me again, which provider can curtail the use of "X-Mailer:  
CloakedSender" immediately?

Only the network provider knows who owns the equipment, as they  
receive payment for the network access they provide.  Their response  
might be to notify these owners.  If the abuse represents criminal  
activity, such as distribution of malware, the network provider may  
also block access.  Either way, the owner of the system become aware  
of the issue.  Since much email abuse is being emitted from  
compromised systems, black-hole/block-list operators coordinating with  
network providers do play a critical role in abating this problem.   
While performing this function is not required, not performing this  
function can not be described as a best practice.

How can a BL operator establish relationships with millions of a  
network providers' customers, without expecting network providers  
to intercede?

How do you define "establish relationships"?  If I publish  
dnsbl.noprimes.org, have I established relationships with all users  
of prime-number IP addresses?

When the goal of the black-hole/black list is to enumerate addresses  
emitting abuse, then offering notification to the associated network  
provider dramatically changes the scope of what is being rated, form  
billions of users, to thousands of providers.  Rating providers and  
excluding the worst is often effective.

Only network provider can establish AUPs,

Anybody can establish an AUP for his own property.  Lots of web  
boards have AUPs without being network providers.

Access to the Internet is granted by network providers.  Their  
customers can run any number of services that should constrain their  
activities to comply with that of their network provider.

While few black-hole/block list operators are able to coordinate  
with network providers and thereby prevent abuse at the source,  
_no_ other approach is as effective or as robust.

So you claim; but so what?  Why should there be any obligation on  
anybody based on your claim (even if true) that something is the  
most effective or robust approach?

Ignoring the role of the network provider can not be seen as a best  
practice when rating IP address space.

A level of trust is required between the BL operator and the  
network provider to be both effective and to improve safely.

Since many network providers are quite untrustworthy, that alone is  
reason to avoid notifying those you don't know.

The level of detail within notifications would be where trust would be  
demonstrated.

Defining a BL mode of operation that asks the least of the network  
operator, also does the least in terms of curbing abuse.

Nobody else is obligated to act according to your beliefs about what  
is the most effective.

When asking about the BL being gamed, a fair amount of hand waving  
commenced.  Of course anyone can pretend to be doing something about  
email abuse.  Being effective requires at least which network provider  
is permitting the abuse.

Currently, few BLs rate domain names.

So?  This isn't a democracy with each BL having one vote.

This draft is attempting to establish guidelines, where currently the  
vast majority of BL operators pertain to IP addresses emitting email  
abuse.  Rather than ignoring these issues, separate sections could  
enumerate how these other types of lists can "best" server their  
function.

IP addresses resolved by the name or used by the name server may  
serve as a reference identifier.

Especially for those domains hosted on zombies with 60 second TTLs.

Be careful.  This may occur occasionally when using a provider's  
resolvers.

In many cases, only the network provider can be identified as  
being associated with the address space in question.

In many cases, nobody can be.

This is simply not true, or the packet could not be routed.

What is the address space for "X-Mailer: CloakedSender"?

The IP address used by the SMTP client, the IP address being queried,  
represents the provider.  See above.  This information must be  
included in this draft, or it is lacking essential inforamtion.

Will there be any recommendation regarding the notification of  
listings?

The listing is its own notification.

No. The goal is to stop the abuse at its source.

Whose goal?  Nobody else is required to act according to your goals.

A best practice should offer this as a goal, of course.

My goal is to identify prime numbers.

Why would you describe this as a black-hole/block list?

As such, prior notification of a listing given the network provider  
can then be directed to their customer.

Lots of things "can be".  The fact that something "can be" does not  
suffice to create obligations.

Network providers are the only entities able to assert governance.   
Rather than attempting to rate billions of individual users, rating a  
few thousand network providers dramatically reduces the scale of the  
the assessment.  BL operators efforts in notifying the network  
providers is not an obligation, but without such notification, BL  
operators will not be as effective in abating abuse.  Abating abuse  
should the goal of a best practice.

-Doug

_______________________________________________
Asrg mailing list
Asrg(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/asrg