hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Kan Zhang <...@yahoo-inc.com>
Subject Re: Design for security in Hadoop
Date Wed, 25 Mar 2009 20:43:28 GMT

On 3/25/09 1:04 PM, "Kan Zhang" <kan@yahoo-inc.com> wrote:

> On 3/25/09 12:15 PM, "Amandeep Khurana" <amansk@gmail.com> wrote:
>> On Wed, Mar 25, 2009 at 2:49 AM, Doug Cutting <cutting@apache.org> wrote:
>>> Amandeep Khurana wrote:
>>>> 1. The Jira covers only authentication using Kerberos. I dont think
>>>> Kerberos
>>>> is the best way to do it since I feel the scalability is limited. All keys
>>>> have to be negotiated by the Kerberos server.
>>> The design in HADOOP-4343 seeks to minimize the number of key negotiations.
>>>  Do you think that's insufficient?  If so, please add a comment on that
>>> issue.
>> The NN doing key negotiations is fundamentally not feasible. Thats the
>> limitation of Kerberos and there's only a certain degree to which it can be
>> optimized. The design I proposed in the paper is a little different from
>> Kerberos, where the clients negotiate the keys. This frees up the NN from
>> the responsibility to do this task.
> You've lost me. What are you referring to when you say key negotiations? As
> far as I read from your paper, you didn't propose anything new for the
> authentication between NN and the user, simply mentioning it will be a
> Kerberos like protocol. If you are referring to those capabilities for
> accessing DN, those are issued by NN, right?
My bad. I read your doc again and I guess you are referring to the protocol
you proposed in the paper for the authentication to datanode using namenode
as a trusted third-party. But the namenode is certainly involved in the
issuing of the ticket, right? Whereas if you use Kerberos, that task can be
off-loaded to the Kerberos KDC.


View raw message