Routing

When issue "show interfaces bri0" it shows "Up and Up (spoofing)". Why spoofing? Is that because the interface is not really up but it has dialer rules set to the interface and ready to be up? What if there is no dialer rule setup? Will it show as do...

Without using sub interface, we can avoid situation such as split horizon issues hampering routing updates on a frame relay network by using "no ip split-horizons". Will this kind of configuration fix the problem the same as using sub interfaces? Is ...

"In ISDN, each B channel has its own SPID which can have more than one assigned SPID" so, at lease one SPID is required? Or it is totally optional (not require at all)? Or it is always required, in ISDN, but it might be dynamically assigned by the pr...

Does one physical bri interface have many B channels inside? Is "bri0" interface referring to a physical cable? How is the ISDN interface/cable look like? Is it just like a regular serial interface? What about D-channel? Where is it? Is D-channel als...

"In PPP, the password configured on both routers must match" Is this statement correct? Or just match the other end hostname and password? Ex. RouterA has password of Cisco and RouterB has password of ABC. Can I configure RouterA to have "username Ro...

"LMI is the protocol used between a DCE and DTE to manage the connection. Signaling messages for SVCs, PVC Status messages, and keepalives are all LMI messages", what is SVCs mean?

Why can't we use HDLC encapsulation for ISDN? Is PPP the only encapsulation type that is valid for ISDN?

What is "no fair-queue" which is the result from "show run" command, under interface BRI0/0 mean?

What is "router2(config)# controller t1 0/0" -> "router2(config-controller)# framing esf" -> "router2(config-controller)# linecode b8zs" -> "router2(config-controller)# pri-group timeslots 1-24" ? Can someone explain what does each command mean? Wh...

"Output for the show interfaces command shows an entry for DLCI followed by a number. This information is no the DLCI number associated with the interface" so what is that number?

Can I use CHAP/PAP authentication over normal Ethernet standard? Or CHAP/PAP must be used with PPP only and I need to configure Ethernet over PPP first? Or Ethernet has better way of doing authentication and PPPoE is not useful at all?

Is CHAP use case sensitive user id (hostname) and password?

To setup PPP authentication, we use "router1 (config) # username router2 password cisco" which is set in a GLOBAL configuration. What if we have more than one destination? Just type more of this command and then it will try all of them in order? Or i...

Does PPP encapsulation type required clock rate? Or only HDLC will need clock? or clock will be required only if I use serial interface don?t care about encapsulation type used?

In Dialer Profile, What is "router1 (config-if) # dialer pool-member 1", "router1 (config-if) #interface dialer 1", "router1 (config-if) #dialer pool1", "router1 (config-if) # dialer remote-name router2"? Can someone explain what does each command me...