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Saturday, February 19, 2011

Going for CCIE Voice

I have been working on Voice for quite a while. I have been around since the call manager 4 days. I took about 15 month break to work in the normal route/switch world and that has helped me tremendously, but I have a love for voice and that's where I"m back too. I recently worked with a TAC engineer who I work with often and we discussed my daily job and it looked like I could go straight to the IE voice with some back filling of topics I'm weak in. I have decided to go for this. Stay Tuned As I post my way through tackling the written and the lab.

Friday, February 18, 2011

Don't let people SIP from your cup

Toll Fraud has been around for ages. Weather it was the Phreakers with there whistles or people using social engineering to get outside dial tone by calling a trusting receptionist its been easy to steal long distance or Internatonal calling if you were creative. In the new world of SIP, toll fraud has followed the new technology. I got a call from a customer about there 800 number being busy. A quick look at the router reviled that all 23 lines of there PRI was being used. The IT manager said thats not true. So I figured he may be getting hit by toll fraud. The IOS output also showed me that all the calls were coming in then being sent to the PSTN overseas. We shut down the SIP dial-peers and bounced the PRI since we didn't know what calls were legit. A quick google search of SIP toll fruad showed us how easy it was to do. Newer versions of IOS 15 have features in to block it. You can view them on the link below.




In the end this has been posted a few times on a lot of blogs. Protect yourself and keep your customers happy.