April 2008 Archives

I believe Penn State's VoIP users will be really keen on CM6's built-in presence and busy-lamp speed-dial features. These two go hand-in-hand and are one of those "it's about time!" sort of things. Busy-lamp speed-dials allow a user to set up normal speed-dial keys that display, using graphical icons and the color of the button (if using a capable phone), whether that number is on-hook (available) or off-hook (busy). It's a speed-dial with status information. This is a far better way of monitoring line availability than setting up shared line appearances just for that functionality, which we do today. Another cool trick, enabled by the presence feature: you can see those available/busy icons in the call lists, too. Now, when I look in my missed calls list and see that I missed a call from the boss, I can also see right there in the list if the boss's phone is busy and decide whether or not it's a good time to call back.

I disagree with the instructor's comment on Tuesday that SIP on endpoints "sucks." It's good that CM6 fully supports the SIP protocol for trunking and endpoints, and it gives administrators a lot more options including remote softphones on various platforms (Cisco's IP Communicator softphone is Windows-only). On the other hand, the SIP firmware for the Cisco IP phones is ridiculously bad, and I can see no reason you'd want to use Cisco IP phones with SIP firmware on Call Manager. The features just aren't there. The third-gen Cisco phones have better SIP firmware and could be used with a third-party PBX, but there are a number of less-expensive alternatives.

The three-day course that Doug and I are attending is on upgrading from CM 4 to 6 and becoming familiar with version 6, including understanding some of the new features and noting some of the changes in existing features.

• Communications Manager 6.x is stable (comparable to 4.1.3; contrast with 5.x). Statement based on qualititative data (customer discussion in users groups, at training classes).


• 6.x - lots of SIP support. SIP on local endpoints "sucks" (says the class instructor, who is not a Cisco employee) - not because of CM's support of it but because of limitations of SIP. SCCP is a high quality protocol for local endpoints. Use SIP for remote/soft clients.


• Operating system is Linux based on RedHat distro; database is IBM Informix.


• Appliance model restricts access to filesystem and database. My reaction is to want to fight against this but can see the benefits of closing this up. Access to database for CDR: no ODBC. Can push out the CDR records to an external server on a regular interval. (CSV)


• Realtime Monitoring Tool (RTMT) is improved and is now a primary way of accessing many data/statistics of CM.


• "Workspace Licensing" - the Standard offering contains most of the PSU per-user needs including IP phone, voice mail (Unity voice-mail-only), user control of devices, plus softphone (IP communicator) which we are becoming more interested in. IP contact center agents would still need to be licensed individually.

The actual upgrade process is mostly automated using provided upgrade tools. Some files need to be copied manually from the 4.x installation. Upgrading CM itself is not too bad. The devil is in the supporting applications, namely Unity and CRS (IP contact center and IVR). Unity 5 supports both CallManager 4.x and 6.x and so can be upgraded prior to CM. CRS 3.5.4 is not supported with CM 6.x. The upgrade path here would have to be CRS to version 4, then upgrade CallManager and CRS immediately afterward to the version that works with CM6. We felt bad for others in the class who had a large suite of Cisco IP telephony apps hooked into Call Manager.

Nothing may seem more ordinary and un-newsworthy than DHCP. But when DHCP is not functioning, it ends up being news and disrupting the entire network.

Recently, Nominum, provider of the software Penn State uses for DHCP, published a press release and case study proclaiming 100% DHCP uptime for four years at Penn State and describing our use of DHCP to support VoIP, wireless and other applications.

In large VoIP installations, DHCP, TFTP and possibly some other low-level network services are vital in the provisioning of endpoints. As of today, we have just over 12,600 phones relying on these services.

To my thousands of loyal RSS readers, (and by that I mean Chris K.) sorry for the republishing of all my entries today. I hope you enjoyed re-reading them. Actually, it's the result of upgrading from MovableType 3 to version 4 provided by ITS. Here are the two gotchas I encountered:

• The new default for blog entries uses hyphens instead of underscores to create the permalinks. If you care to keep your permalinks consistent when you upgrade your blog, you can set MT4 to use underscores. See this very short thread.


• My favorite browser, Opera, doesn't work well with the MT4 admin interface for editing templates. I would say that I fat-fingered something but the quirkiness I encountered makes me think instead that Opera didn't correctly interpret the javascript being used there. I fixed the problems with Firefox. Use Firefox if you're editing templates in MT4.

Coming up next week: Cisco training on upgrading from Call Manager 4.x to 6.1. I'll post some notes and thoughts related to Penn State's implementation if permitted.