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New Member

why the dialer map command need to provide the remote host name?

In DDR config,the dialer map command such as:

dialer map ip name central 2222222

the name central refers to remote host name.According to the command reference,the name is used for authentication. But in authentication such as pap authentication and chap authentication ,the dialing router just need to provide it's own host name and password, and the dialed router receive the authentication information and looks for it''s database such as commands:

username aa password bb for authentication.

the dialing router doesn't need to know the remote host name for authentication.

So why the dialer map command needs to know the remote side name for authentication?

New Member

Re: why the dialer map command need to provide the remote host n


Maybe this will explain better?

The hostname of the router is used to identify the router to another router when sending Challenge Handshake Authentication Protocol (CHAP) messages.

The username command is required when used to specify the CHAP secret message to use when challenged by another router. The two routers that need to talk must share the same password.

The dialer map is used to distinguish between different remote sites, which can be connected at various times. A map is required for each site and each protocol used. The remote name is the hostname of the other router.

Dialer maps provide the network-layer-to-link-layer mapping required by the router to successfully encapsulate, or send packets out, an interface.

The name is essential for identifying calling routers, through the use of CHAP. CHAP also provides some security, but is included in this basic configuration mainly because it allows identification of calling routers. In the general case, CHAP is required for identification of the calling router because calling number delivery is not always possible.

Key Configuration Parameters

hostname [name]

username [name] password [secret]

dialer map [protocol] name [remote-name] [broadcast] speed 56 [phone-number]

ip route ´network´ [mask] {address | interface} [distance]

I hope this will do??

Greetz, Martin Dekker

New Member

Re: why the dialer map command need to provide the remote host n

Thanks a lot.

But if only use pap for authentication,do i still need to specify the remote router name in dialer map command?


Re: why the dialer map command need to provide the remote host n

Dialer maps are (mostly) required for dialout reasons; in that case, you should have the name in the map. For dialin, dynamic maps are built using the name that the remote used for authentication. This is irrespective of CHAP or PAP.

Names are required on dialer maps so that we have an association between who is connected,

what their IP address is, and what interface they are connected to. Names are not required for authentication reasons, that is handled separately. Also, during IPCP negotiations we use the name (versus the phone number) to figure out which map to use and therefore which address to enforce upon the remote we are dialing to.

New Member

Re: why the dialer map command need to provide the remote host n

In your opinion,dialer map names are not required for authentication reasons,

so if i don't config the name ,i can still dialin by another router or dialout to another router without problem,so why do i need the dialer map names? Sorry,i should say that i still could not understand what you mean.


Re: why the dialer map command need to provide the remote host n

There are two issues: dialing and communicating. A dialer map without a name will still be able to dial, but you may have problems communicating. A dialer map with the name allows us to correspond an address with the name (useful when negotiating IPCP), and to know who we are currently connected to. It has less to do with authentication and more to do with internal administration on who we are connected to. In the end, adding a name to a map should not be a burden, anyway.