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New Member


pap & chap is the built-in security feature of PPP

in PACKET mode or CIRCUIT mode?????


Re: PAP and CHAP

First of all, PAP or CHAP is not built in - ie, it's not on by default, it's not required. Authentication

using PAP or CHAP occurs after LCP has been negotiated, so I guess you would refer to this

as PACKET mode.

New Member

Re: PAP and CHAP

why do you answer me like that???

please don't guess ..

and in fact PAP and CHAP are built-in security feature.

you can find it in CID of ciscopress if you don't beleive me that it's built-in security feature.

New Member

Re: PAP and CHAP


I think that Mark didn't mean to be rude. In fact he is right, because you can have PPP and not have authentication. Usually you use authentication when you use PPP on dial on demand scenarios, but PPP encapsulation can work without it. Of course, if the other side demands authentication you have to use it.

Regarding the CID book... no comments.



New Member

Re: PAP and CHAP

Sorry about my question.

...In fact,you know, I passed CID and get CCDP.

I've got a question like this.

I just want to know that it was true or not.

built-in, packet mode or

buitl-in, circuit mode.


I can find the answers from some theories,but not every question.

Thanks in advanced and appreciate for who give me the answer.


...... Keep smile...


Re: PAP and CHAP

Please describe your definition of "built-in" (don't know if you need a smiley face to show that I'm not intending to be rude). PPP authentication is disabled by default:

New Member

Re: PAP and CHAP

"built-in" means ->

not "option" and not "exclude" feature of PPP.


Just like Intel Pentium 4 has a built-in 512k L2 cache.

Intel 486 has an exclude 64k L2 cache...


like this....all right???


some words, I know exactly.

but some technical or general words are difficult to


if i'm wrong ,please fix it ...

and Thanks in advanced.


Re: PAP and CHAP

Authentication is an option to PPP; this is not per cisco, but per the spec. See the introduction of RFC 1994.

In fact, note that authentication is a separate RFC from the PPP RFC, 1661.

So I guess authentication is not built-in.