One of the first things to make sure when an H.323 gateway will not work with Cisco Unified Communication Manager (CUCM) is the IP address configuration. This is a common mistake where engineers would configure the gateway in CUCM using its voice interface IP address and would have no problem calling out from IP phones to the PSTN, but would fail on the inbound calls. The reason is that the gateway was using a different IP address (than the one configured on the voice vlan) to contact CUCM and CUCM would reject the call setup packet. Read more
This is a short post about something I recently found out, it also continues questions I had from previous posts about 'when will Cisco support additional hardware', as it was asked at: http://www.networkworld.com/community/blog/first-look-call-manager-85#co... Read more
This is going to be an add-on post to a documented procedure, which can be found at: Read more
http://www.cisco.com/en/US/products/ps6120/products_configuration_example09186a00809f0d75.shtml
When I needed to configure the same functionality that is described in this tech note, I ran into a few issues and thought it may help others if I share my knowledge around that.
Cisco has two main options when it comes to vpn clients, IPSEC or anyconnect.
IPSEC has been there for a while, since the vpn3000 days, and to date, it is probably the most known and used vpn client among Cisco customers. At some point when 64bit OS started to be popular there was no IPSEC client option and it almost eliminated this option, since it did not have 64bit support. Then, the 64bit support was added and that made it a viable client for today's Windows 7 based OS. Here is an IPSEC client screen shot: Read more
Version 8.5 was announced and is orderable since December 2010, although the data sheet is not up yet, there are a few new features that can and should be mentioned about it. It is not the most exciting version that has been announced, the new features are more administrators then users facing.
Here is a list of the important ones (at least in my humble opinion): Read more
A year has passed and it is time for a short summary of this blog and the world it resides in.
Starting with the most popular posts of this year:
the most accessed one was:
First look into Call Manager 8.0, point taken and the one for version 8.5 is in the make.
Second place goes to: Read more
Configuring QoS is not a hard task for me, with all the time that I spent in front of it while studying for certs and or configuring network devices it is easy. Nevertheless, it is time consuming and requires many details that I prefer to not memorize if I do not have to.
Well, apparently there is a tool for that, which I got to know through this blog and wanted to share back. It is called LiveAction and is the product of a company called Action Packed Networks (http://www.actionpacked.com). Read more
A small diversion from my usual tech posting, but I thought this will be a helpful knowledge for other Cisco professionals. While searching the app store for something else, I stumbeled upon this app which was described as:
Cisco iPhone Application.
Uncover a new way to interact with Cisco.
The Cisco application for iPhone allows you to:
• Get the latest news and promotional offers. Read more
• Find events and Cisco partners in your area.
• Search for content.
• Play our latest videos or podcasts.
A recent product security announcement from Cisco and a blog post by Chris Jackson made me feel it may appear that SIP trunking is not secure enough as a PSTN (Public Switched Telephone Network) access method. Read more
So it took me some time but finally I got hold of a couple of 7962 and verified that the EMCC config worked. Indeed there was no need to support it in IP Communicator which is why it was not supported. Here are some screen shots, captured during the config process:
SIP trunk configuration settings (need to be on both clusters): Read more
Time to continue discussing my lab attempts with EMCC, which started about a month ago and is still 'work in progress' (mainly due to time constrains). Here is the link to my previous post on it: http://www.networkworld.com/community/node/60986 Read more
As one of the new features in CUCM 8.x, it seems like a good candidate to lab.
This will not be the first time this topic is mentioned on the Cisco subnet, readers are encouraged to look at Dennis Hartmann's post on the subject, still I think it's going to be beneficial to others if I share my lab notes.
To get going I got a hold of the latest Features and Services guide and started to read. It starts on page 269 and continue until page 324 (that's 55 pages). Read more
Call Manger 8.0 has been announced and will begin shipping in April 2010; here are some new features that I can see an immediate benefit in:
It can be virtualized on top of VMware ESXi 4.0 running on Cisco's UCS. Not every hypervisor, not every version of VMware and not on every hardware. The official reason is that it will be impossible to support all hardware or hypervisors, next thing you know someone will open a TAC case saying call quality is bad on his laptop running VMware workstation 5.5. In the future the field of supported hardware/software is expected to grow. Read more
If you ever tried to convert a Cisco IP phone from Skinny to SIP or vice versa, you probably experienced that uncertainty when the phone was rebooting and pulling something from the TFTP but then it stopped.
Usually it's making a progress and after a few minutes and additional load files the phone converts, the same happens when upgrading firmware due to call manager version upgrade or service packs. Sometimes it's not happening at all like you would expect and you are finding yourself starring at a device that keeps rebooting and rebooting and nothing seems to be progressing. Read more
It's this time of the year again, time to look back and analyze the events what shaped this year and years to come. Read more
Although the ISR G2 announcement from Cisco seems like more of the same, but faster and stronger, there are significant improvements related to voice and video that are worth mentioning. Here is a table that shows them:
When the ASA Botnet filter feature was announced I thought that it's an interesting concept and is definitely worth trying. One of the interesting concepts that this feature introduces is the ability to monitor your outbound traffic and to know if there are flows in it that should not be allowed. This is an option with dedicated devices but the firewall is usually focused on inbound traffic and not outbound. Botnets make it important to know what is going out as well. Read more
In the last Network World magazine, I came across an article called 'ROI doesn't always pan out with unified communications' and while reading through it, a few topics came up. To begin with, one must differentiate IP Telephony from UC, the vendors make it hard for us by naming everything the same, but some products are IPTEL, some are UC and some are Video conferencing. When trying to identify an ROI justification for a project, this is an important observation. Read more
How are you tracking the IOS status in your network? It isn't an easy task, even for veteran network engineers (as posted by others before here). With all the bugs, security issues and what not, one can easily get confused.
When I found myself in the situation of deciding if it's time to upgrade or not - and what are the potential issues (open bugs) I'm letting in if I don't upgrade - I decided to revert to an old friend and logged on to Cisco Works Lan Management Solutions. Read more
Getting your mobile phone to ring when your desk phone does is pretty easy, but before walking through it you should understand what makes this functionality work.
The common ground to all the phone numbers is a user account, we need a user account that is allowed to use mobility and is associated with the desk phone and the mobile phone, and this tells the system to link a desk phone to a mobile phone.
Avner Izhar is an experienced IT professional; he has 14 years of experience in the networking area, on multiple continents, and has filled positions in post sales, pre sales and training. He currently holds CCIE in Voice (#15999), CCSI (#31623), CCVP and others. He is also the author of two CCIE voice training related books: CCIE Voice Technology Workbook and CCIE Voice written study guide, both published under NLI. When he is not blogging for Network World, he work as a Consulting System Engineer for World Wide Technology.
Through this blog, Avner will share his personal experience and assist junior and senior engineers in their IT tasks.