Re: OT: PPP PAP/CHAP One-way autehtication

To understand this command, you need to think of dial-up scenario
where you have "dialing" and "dialed" side. I.e. one is initiating the
session, while other accepts it. In sync. ppp like the one we have
with back-to-back serial lines, we don't have that clear
distinction... even though it can be configured. If you are asked to
do something along those lines, you need to ensure which end will
behave like what.

The best way to understand "ppp authentication X" is to read it is
"please, authenticate to me using X".

--
Marko Milivojevic - CCIE #18427
Senior Technical Instructor - IPexpert
YES! We include 400 hours of REAL rack
time with our Blended Learning Solution!
Mailto: markom_at_ipexpert.com
Telephone: +1.810.326.1444
Fax: +1.810.454.0130
Web: http://www.ipexpert.com/
On Wed, May 5, 2010 at 16:23, Syed Khalid Ali
<khalid_khursheed_at_hotmail.com> wrote:
> Marko,
> Thank you for the quick example. I am confused with the command "ppp
> authentication callin" as indicated by the doc at cisco website. Can you
> elaborate this command? The doc says that it is required on client side!
> Below is the snippet:
> TheB callinB option says the router that theB ppp authentication pap
> callinB command is configured on will only authenticate the other side during
> an incoming call. For an outgoing call, it will not authenticate the other
> side. This means the router initiating the call does not require a request
> for authentication (AUTH-REQ) from the other side
> thanks
> Khalid
>
>> From: jastorino_at_ipexpert.com
>> Date: Wed, 5 May 2010 11:49:22 -0400
>> Subject: Re: OT: PPP PAP/CHAP One-way autehtication
>> To: markom_at_ipexpert.com
>> CC: khalid_khursheed_at_hotmail.com; ccielab_at_groupstudy.com
>>
>> Yes as Marko has shown the side with "ppp authentication pap/chap/eap"
>> is initiating the authentication (authenticating the other side).
>> When a router (in this example R2) receives the authentication request
>> it responds per the configuration. In this case, R2 responds with the
>> username of R2 and the password of ipexpert. Notice R2 does not need
>> "ppp authentication ..." for this to work as it is 1-way
>>
>>
>>
>> On Wed, May 5, 2010 at 10:15 AM, Marko Milivojevic <markom_at_ipexpert.com>
>> wrote:
>> > On Wed, May 5, 2010 at 10:08, Syed Khalid Ali
>> > <khalid_khursheed_at_hotmail.com> wrote:
>> >> Group:
>> >> Can any one explain PPP 1-way authentication. I read the document:
>> >>
>> >> http://www.cisco.com/en/US/tech/tk713/tk507/technologies_tech_note09186a00800
>> >> 93c6f.shtml#ppp_authand tried the same example on GNS3 with two router
>> >> connected with back to back serial. But it is not working.
>> >
>> > When something "is not working", it is always a good idea to post your
>> > configurations, so we can show you what you probably did wrong... :-)
>> > Here's a quick example of R2 authenticating to R5, but not the other
>> > way round.
>> >
>> > ! R2:
>> > hostname R2
>> > !
>> > interface Serial0/2/0
>> > ip address 25.25.25.2 255.255.255.0
>> > encapsulation ppp
>> > ppp pap sent-username R2 password ipexpert
>> > no shutdown
>> > !
>> >
>> > ! R5:
>> > hostname R5
>> > username R2 password ipexpert
>> > !
>> > interface Serial0/2/0
>> > ip address 25.25.25.5 255.255.255.0
>> > encapsulation ppp
>> > ppp authentication pap
>> > no shutdown
>> > !
>> >
>> > --
>> > Marko Milivojevic - CCIE #18427
>> > Senior Technical Instructor - IPexpert
>> >
>> > YES! We include 400 hours of REAL rack
>> > time with our Blended Learning Solution!
>> >
>> > Mailto: markom_at_ipexpert.com
>> > Telephone: +1.810.326.1444
>> > Fax: +1.810.454.0130
>> > Web: http://www.ipexpert.com/
>> >
>> >
>> > Blogs and organic groups at http://www.ccie.net
>> >
>> > _______________________________________________________________________
>> > Subscription information may be found at:
>> > http://www.groupstudy.com/list/CCIELab.html
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>>
>>
>>
>> --
>> Regards,
>>
>>
>>
>> Joe Astorino - CCIE #24347
>> Sr. Technical Instructor - IPexpert
>> Mailto: jastorino_at_ipexpert.com
>> Telephone: +1.810.326.1444
>> Live Assistance, Please visit: www.ipexpert.com/chat
>> eFax: +1.810.454.0130
>>
>> IPexpert is a premier provider of Self-Study Workbooks, Video on
>> Demand, Audio Tools, Online Hardware Rental and Classroom Training for
>> the Cisco CCIE (R&S, Voice, Security & Service Provider)
>> certification(s) with training locations throughout the United States,
>> Europe, South Asia and Australia. Be sure to visit our online
>> communities at www.ipexpert.com/communities and our public website at
>> www.ipexpert.com
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
>> _______________________________________________________________________
>> Subscription information may be found at:
>> http://www.groupstudy.com/list/CCIELab.html
>>
>>
>>
>>
>>
>>
>>
>
> ________________________________
> Hotmail: Powerful Free email with security by Microsoft. Get it now.
Blogs and organic groups at http://www.ccie.net