ISDN is just a large subject on both your Cisco CCNA and BCRAN CCNP tests. While several ISDN topics seem simple, its the details that make the difference in the exam room and working together with ISDN in production networks. Configuring and troubleshooting multilink PPP is just one of the skills youll have to pass both of these demanding exams.

With BRI, we’ve got two B-channels to hold information, and both of them have a 64-kbps capacity. You may think it’d be a good idea to own both channels functioning before one reaches capacity, and it’s a good idea Problem is, it’s not really a default behavior of ISDN. Until the first one reaches capacity the 2nd b-channel will not start to carry traffic.

With Multilink PPP (MLP), a bandwidth capacity may be set that may enable the 2nd b-channel to carry knowledge before capacity is reached by the first channel. The arrangement for MLP is simple, but often misconfigured. We’ll use our close friend IOS Help verify the measurement this command uses.

Enabling MLP is just a three-step process:

Permit PPP on the link

Enable MLP with the control ppp multilink

Determine the limit of which the second b-channel should start holding information with the dialer load-threshold command.

Let us say you wanted the second b-channel if the first channel reaches 75% of volume to start out carrying knowledge. It would sound right that the command to do this would be dialer load-threshold 75… However it is not.

R1( config )#int bri0

R1( config-if )#ppp multilink

R1( config-if )#dialer load-threshold??

Load tolerance to position still another call

The dialer load-threshold value is dependant on 255, not 100. To have this order carry the make at a certain percentage, multiply that percentage in decimal format by 255. Below, I multiplied 255 by.75 (75%) to reach at 191.

R1( config-if )#dialer load-threshold 191??

Both Threshold choice centered on max of outbound and inbound traffic

inbound Threshold decision predicated on inbound traffic only

outbound Threshold decision centered on outbound traffic just

R1( config-if )#dialer load-threshold 191 both

As shown by IOS Aid in the above mentioned arrangement, dialer load-threshold has extra options as well. You are able to configure the interface to take into account only incoming, outgoing, or all traffic when calculating when to create the next station up.

Establishing Multilink PPP is merely one of the skills youll need certainly to make your CCNA and pass the CCNP BCRAN assessment. Dont ignore ISDN on Ciscos certification tests! construction loading platforms