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September 2011

VoIP Newbie

hi guys, i am new ( not so new !) to VoIP and now i am saddled with delievering communication between CUCM (MCS 7800), ver 6 and  Panasonic Kx TDA 100 with H.323.
Both devices are on different sites connected by a leased wan connection. CUCM has a 2811 as the main router, plus switches and 7911 phones, while the other site has the Panasonic PBX, 2960G switches and a 3560G L2/L3 switch.
I need help to make this project a success.

End of Life Announced for Cisco 7200 NPE-G1

Cisco this week has announced the end of sale and end of life dates for the 7200 Series NPE-G1 Network Processing Engine. This is an older routing engine that is definitely showing its age compared to newer platforms that are available.

The last day to buy the NPE-G1 is February 27, 2012. Last day for hardware support is February 28, 2017. The recommended upgrade path is the ASR1000 series.

Full details are available in the official announcement.

The end of Cisco's Service Provider Voice portfolio

I think one of the important things concerning Cisco has gone unnoticed in the previous weeks - and that is, basically, a complete shutdown of their voice portfolio for service providers.

1) PGW2200 - class 4 softswitch, used widely in Telecoms in Europe and the rest of the world

2) BTS10200 - class 4/5 softswitch, used widely by cable operators in the US

3) MGX8800 product line - a carrier grade voice gateways, used extensively in PSTN/VoIP deployments

Place of codec within RTP stream

Hi all! Ive been wondering a lot on the actual place of the voice codec during RTP communication. I know, when talking about SIP session, the codec information is exchanged within the SDP field in the session parameters negotiation. But i wanted to know exactly, during the actual communication, when RTP streams are flowing, where does the codec actually operate? is it the IP PBX who's in charge of it, or is it the phones themselves? If last option happens to be the case, why do whe require to buy licence for g729 codec to be able to use 8kbps on our line,while they phones already have embedded support for this codec? Im still working on improving my english, so i hope u guys we'll be able to understand my question. Thanks!

How to configure a Cisco router to be a frame relay switch

If you are studying for the TSHOOT exam, it is a good idea to familiarize yourself with the topology. I've been working on creating a lab that mocks the TSHOOT topology, and it has forced me to recall how to setup a Cisco router to act like a Frame Relay switch. 

Here is the topology that I've built. As you can see, it closely resembles the topology that Cisco has provided on their site. Since their doc doesn't provide specific DLCIs, I've used the most logical numbers I could think of.


The first step in configuring a Cisco router to act like a frame relay switch is to enable frame relay switching:

Cisco SG100-16 Unmanaged Switch

Need more Gigabit Ethernet? Don't need it to be a managed switch? This 16 port 10/100/1000 Cisco switch might be a quick and easy solution for you.


The Cisco SR2016T 16-Port Rackmount 10/100/1000 Gigabit Switch (A.K.A. SG100-16) is currently listing for below $200 USD and has several appealing features:

Suggest Network Tool

Need to know is there any tool available to check what and which data flowing in UNMANAGED SWITCH, we can easily check over MANAGED SWITCH. But I want to test where unmanaged switch are levied.

Cisco 1841 and IPV6

I have a cisco 1841  with IOS Ver. c1841-advsecurityk9-mz.124-25b.bin
does anybody know if it supports IPV6?
I typed in IPV6 unicast-routing and it does not work.
I just bought this from ebay

Serious issue on CCNP CBTnugget

Please, I will be most grateful if Jeremy or any can rescue me on his CCNP Route Video csco_642_902_06 & csc0_642_902_7. Thou, he really jumped some steps. I was following his video step, after my configuration, I could ping from HQ to both EAST and WEST but I couldn't ping EAST from WEST and vice versa. So, please, what's the hidden configuration there?
Please i will appreciate your reply.


How to configure an IPv4 GRE tunnel to carry IPv6 traffic

Continuing the review of the TSHOOT Topology, on the IPv6 network map there is a GRE tunnel that is configured between Router 3 and Router 4. This tunnel is in place to allow IPv6 traffic to traverse the IPv4 network. So, while reviewing the IPv6 tshoot topology, I decided to try out the tunnel configuration.

There are several ways to configure tunnels to allow IPv6 traffic to traverse IPv4 networks (and vice versa). This post will be focusing on a GRE tunnel configuration. If you want to review the other ways to create tunnels, i.e.  Automatic IPv4-Compatible IPv6 Tunnels, IPv6 Rapid Deployment Tunnels, and Automatic 6to4 Tunnels, I've included a link below to a great resource on Cisco's website that shows some great examples of other tunnels.

I threw together the following network diagram to provide a visual of what we are configuring: 


Automatic 6to4 Tunnels

While reading up on IPv6 tunnel configurations, I came across this way cool video on configuring 6to4 tunnels. Keith Barker definitely knows his stuff on this topic and makes it interesting and easy to follow. Check it out:

Mobile CCIE Labs

If you are planning on going for the CCIE R&S or Security and you live in a country where the lab is not administered, it can be a challenge to get to the testing center, let alone pass the exam! Cisco has had a program in place to combat this very issue for quite some time called the Mobile CCIE Lab. The program allows you to register to take the lab exam in your city or one closer to you than in a foreign country. The benefits here, of course, are potential savings in travel expenses and missing less work ( even though you might not be missing it).

For a complete schedule of where and when the lab will be available, or if you are interested in learning more about this program, check out the official Mobile CCIE Lab page at Cisco's website.

ICND1 Subnetting confusion

I was creating some of my own practice subnetting questions and I'm kind of confused here.  I might just be making a mistake, but when I follow the directions as lined out in video 19 i am coming up with some strange results.

For instance, lets say I'm subnetting a class c network and want to create 8 networks.
So I line out my network and host bits like so
128 - 64 - 32 - 16 - 8 - 4 - 2 - 1
0  -  0  -  0  -  0  -  [1  - 0  - 0  -  0]  -  four bit positions to make 8
so I represent these four bits in the binary and convert

11111111 11111111 11111111 11110000
256-240 = 16 for my increment, but this gives me 16 networks instead of the 8 that I need.  

Cisco Certified Technician (CCT)

The newest addition to Cisco's line of certifications is the CCT, or Cisco Certified Technician. Released in August of this year, the CCT certification has three different areas of focus:

Each certification focuses on the on-site maintenance and support of Cisco equipment in each specific area.

You might be wondering what is the difference between the CCT and the CCENT? Cisco explains that and several more questions in their FAQ, but for those not interested in reading through all of that, here's the basics...

How to configure multiple NTP time sources in Windows Server 2008 (R2)


Over the past few weeks, I noticed my computer's time was drifting several minutes behind. This actually caused me to be late to a couple different meetings because I kept working on my computer instead of leaving the house. Well, since it's a Saturday and I had some time to fix the problem once and for all, I wanted to share what I've learned since it took longer than I expected to configure NTP on a Windows Server.

It all began several months back when I setup a Windows 2008 R2 Server and thought "wouldn't it be cool if I set my desktop's clock to update from the server instead of a reliable external source?" So, I unwittingly redirected my desktop from its reliable to my server's ip address with the assumption the server was already getting it's time from a default external source. Hence the source of my lateness months later.

Fast forward to today. I figured it would be a quick 5 minute fix to remote into the server, find some sort of ntp settings tab in a properties window, then add my multiple servers. I should have known better than to assume Microsoft would have added such a logical GUI feature. 

After searching the Internet, reading through several Microsoft technet articles, and testing multiple configurations, here's what I've got...

where to DL Jeremy's .pdf's???

Looking to find out the new location to download the .pdf's Jeremy provides in his CBTNuggets videos. The location he gives in the videos is gone since CBTNuggets redid their website.
Is there a new URL?
Watching CCNA-Security 60-553 and looking for the VPN info/.pdf's

Thanks in advance

the best tool for ip management

For ip address management we use

Question for Jeremy

This is a non technical question but rather a mere curiosity. What nationality are you Jeremy? Or what roots do you have? Here in Romania, there are rumors that you are Romanian or your parents are because your family name is very common here, but rarely we hear it elsewhere.
So can you break the ice and tell us?
Also, I'd like to thank you for your terrific work. It is highly appreciated here.

Which Cisco Router

Hi Jeremy i am a CCNA i just want to know what Cisco router can i purchase to do load balancing for my two internet connections. I currently uses the Cisco RV042 but i don't know if it will be able to carry the load of about 70 users my two connections are 4M each.Also what commands i need to use.

vpn ASA to a Cisco Router (VLAN question)

I want to practise site to site vpns. I have a new asa and right now want to connect it to my 800 series router that is my main router (adsl). I would like to create a new vlan on it and connect it directly to a wan port of asa
Do you think of any issues I might come across with a topology like this?

Dr. Radut