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New Member

Cisco ADSL with no Authentication


I am setting up a Cisco 857 for adsl that does not require authentication according to the ISP. I have got a connection on the ATM0 interface but am not getting a PPP connection?! I have not configured any type of authentication on the dialer interface.

When i run 'debug ppp authentication' I receive

vi2 ppp Authorization required

vi2 ppp no remote authentication for call-outs

Can anyone help?

Many Thanks


Re: Cisco ADSL with no Authentication


typically, for provider connections, the authentication statement would look like this:

ppp authentication pap chap callin

which means that the ISP authenticates you, but not vice versa, could it be that this is what your ISP was referring to ?



New Member

Re: Cisco ADSL with no Authentication

Here is my config:

interface ATM0/1/0

description Connection to ADSL 6.0/768k

bandwidth inherit

no ip address

no atm ilmi-keepalive


dsl operating-mode auto

clock rate aal5 8000000

no clns route-cache

bridge-group 1

hold-queue 224 in

pvc 0/35

encapsulation aal5snap



interface BVI1

ip address x.x.x.x

ip access-group fwingress in

ip nat outside

ip inspect inspect out

ip virtual-reassembly

crypto map vpn-map

New Member

Re: Cisco ADSL with no Authentication

A provider here in holland uses the line number for the authentication, but it uses PPPoA for the transport. You can use the following config (check with your ISP that it indeed uses PPPoA):

interrface ATM0/1

no ip address

no atm ilmi-keepalive

dsl equipment-type cpe

dsl linerate auto

pvc 0/35

encapsulation aal5mux ppp dialer

dialer pool-member 1



interface Dialer0

ip address negotiated

encapsulation ppp

dialer pool 1

dialer-group 1

ppp authentication pap callin

ppp pap sent-username dummyuser password 0 dummypass


This technique is also used for GPRS connections, where there is no authentication, but clients must enter a username and password. The LCP will then (upon establishment of the line) not negotiate PAP authentication as the server is not requesting for it.

Hope this helps


New Member

Re: Cisco ADSL with no Authentication

Thank You all very much. After contacting the ISP myself, (never trust the end user),I got the correct parameters and voila! The second post is similar to my end result. Again, thank you very much...Booda2usa