From: Mark Snow (msnow@ipexpert.com)
Date: Wed Jan 02 2008 - 15:32:23 ARST
Hey Frog,
As Avner accurately mentioned - it is very important to know both
methods - since you never know what requirements you may be given.
Traditional is a bit easier to use - and might be a better candidate
for using in the lab if not given any other requirements that force
you to use the Line/Device
However seeing that the line/device approach is much more powerful -
you should also know this concept well in case you need to use it.
Keep in mind that you have the CCM SRND on your candidate desktop in
the lab - so know it well.
If you only studied the Line/Device approach marginally, but had a
requirement to use it in the lab - you have it all available to you to
refresh from in the CCM SRND on pages 344-351.
An example of a requirement would be one like that described in the
CCM SRND:
"When using the Extension Mobility feature, the line/device approach
provides a natural way to implement the dialing restrictions of a
phone as a function of the logged-in status of the phone."
In other words - you keep your calling restrictions - but your CoR is
now applied so that when logged into a phone at a remote site (across
the wan) your call goes out your new local gateway - instead of across
the wan back to your 'home' site and out that gateway.
In real life this is very important mainly for Emergency Services
calls - where PSAPs aren't even remotely close to being connected to
each other - and and your ANI / ALI information would return the wrong
site address if not going out the proper gateway. Not to mention
significantly reducing wan bandwidth usage.
Do also bear in mind that there are caveats and considerations that
need to be taken into account and they are described in the SRND in
the pages given - namely that:
"When the Forward All calling search space is left as <None>, the
results are difficult to predict and depend on the Cisco CallManager
release. Therefore, Cisco recommends the following best practices when
configuring call-forward calling search spaces ... Always provision
the call-forward calling search spaces with a value other than <None>.
This practice avoids confusion and facilitates troubleshooting because
it enables the network administrator to know exactly which calling
search space is being used for forwarded calls."
AND
"Prior to Cisco CallManager Release 3.1, the concatenation was
performed in the reverse order, and the device's calling search space
came first, followed by the line's calling search space. This reverse
behavior is still adopted by CTI ports and CTI route groups. "
I suppose when Avner said that:
"Guess the vendors workbooks were written by folks who learned it
before there was a partition field under the line ;)"
... he was referring to CallManager 2.4 - before the 3.0 release.
While Vik and I both were working with CallManager back then before
Cisco had acquired Selsius Systems - I'm not sure how that is relevant
to the lab since they never tested any UCM version before 3.3.
*shrug*
We have mostly kept to this based on it's simplicity and getting folks
to understand the basics before moving onto more complicated scenarios.
Though come to any ILT bootcamp we have hold and see that we
vigorously rehearse both of them - Avner should remember this from the
class he took from me in Dallas before getting his IE.
Cheers and Happy 2008 Frog!
Mark Snow
CCIE #14073 (Voice, Security)
CCSI #31583
Senior Technical Instructor - IPexpert, Inc.
A Cisco Learning Partner - We Accept Learning Credits!
Telephone: +1.810.326.1444
Fax: +1.309.413.4097
Mailto: msnow@ipexpert.com
IPexpert - The Global Leader in Self-Study, Classroom-Based, Video On
Demand and Audio Certification Training Tools for the Cisco CCIE R&S
Lab, CCIE Security Lab, CCIE Service Provider Lab , CCIE Voice Lab and
CCIE Storage Lab Certifications.
On Jan 2, 2008, at 6:19 AM, Radioactive Frog wrote:
> Thanks Avner.
> i'll strict to one for exam purpose - traditional and will study
> line/device
> for real life scenario.
>
> frog
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Fri Feb 01 2008 - 10:37:57 ARST