Voip codecs and bandwidth calculation.

So today I have spent some time reading up on voip codecs, and how to calculate bandwidth requirements for a single call with a certain codec. Take for example. G.711 (PCM), which is uncompressed voice data. Its specification says 64kbps raw data output from the codec.
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Nbar is a pretty nifty feature.

So today I watched some material on nbar (Network Based Application Recognition), which is a feature originally used for classification of data, used in QoS to mark packets. It uses very deep packet inspection, to figure out what data is being transfered over the network.
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ONT = QoS? – I think so

So, so far ONT seems alot like its brother-acronym QoS. Watched a few videos today, solidifying knowledge from BCMSN about CoS only being for L2 trunk links and ToS/DSCP being for Layer 3. Figured out the DE bit provides a somewhat rudimentary QoS for frame-relay.
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ISCW Passed.

I just passed ISCW. Im really glad this one is over with. But I have ALOT of reviewing for the material in this one, when i finish the rest of the CCNP track. I could especially feel that not having access to the FW and IPS parts really hurt me.
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IPSec VPN’s – Part 2

So today I have read a couple of more chapters about IPSec and GRE (Generic Routing Encapsulation). I have also watched quite alot of CBT on IPSec VPN’s, which really helped clarify somethings. But I also really think its a hard topic to get to grips with, especially since you only get “half of the story”.
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IPSec VPN's.

Im studying IPSec VPN’s at the moment. There’s alot of terms, protocols and exchanges taking place, and they all use names thats really hard to tie together with what they are doing 🙂 Isakmp for example, what does that do? well, it stands for Internet Security Association and Key Management Protocol.
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ISCW started

So I just started work toward the ISCW. The lab book for this is huge, so I think its going to be alot of lab work, and alot of lookups on Cisco’s doc site for further information. My reason for this thinking is the lack of a self-study guide for the ISCW exam.
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Passed BCMSN

Thankfully I passed BCMSN. Thank god. It was driving me nuts. Passed with an 864, which im satisfied with. I am thinking about my study technique for the ISCW. I need to see if I can structure it somewhat better than BCMSN, where I ended up reading some topics over and over again.
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Trying some reading.

I am trying to get some reading done, even though its extremely hard when im still sick. However, I only got about 5 chapters left in the examination guide. hopefully I can finish them soon, and do some of the last case studies in the lab book.
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Lack of the right equipment.

Lately I have been in the need of the right equipment for quite a few labs. What I really need is some equipment that is able to do both Dynamic Arp Inspection (DAI) and IP Source Guard (IPSG). The dynamic arp part is supported on 3550’s as far as I can see, but IPSG is not.
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L2 security…

Been reading the study guide about L2 security. You can really mess up a whole network very simply, and you can basically take down the whole thing pretty easily if your switches are not configured correctly. There was also alot of things about IP spoofing and ARP spoofing.
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Gateway Redundancy.. Awesome

So im studying redundancy features, especially gateway redundancy features. I think this is some impressing technology. Basically there are three versions, HSRP (cisco proprietary), VRRP (IEEE Standard) and GLBP (cisco proprietary). HSRP was introduced in 1994, and VRRP in 1999, GLBP is alot newer, introduced in 2005.
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CEF – A topic in disguise

Been reading about CEF yesterday. It doesnt take up much of the exam blueprint, nor CBT nuggets coverage of it. However, it seems that theres more to this than what meets the eye. I also need to figure out what CEF is doing in routers.
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Inter-Vlan connectivity and enhancing switch features.

Today I have spent about 2,5 hours studying different features that enhances the switched network. This includes labbing up BPDU guard, Loop guard, UDLD Aggressive mode, BPDU filtering. Also I find the automatic error recovery feature very interesting. You can set certain causes to put an interface into the errdisabled state.
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Spanning-tree issues.

I have been working my a** off trying to understand STP just fairly well. Its a hard topic, especially with Rapid STP. I have struggled with the synchronisation/proposal/agreement thing. It has helped seeing it on the equipment though. An alternate port can be switched to immediately.
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(3) EIGRP – Labs

So yesterday, I started with all the lab exercises that has to do with EIGRP. I did the one in the self-study guide, and one (2.7.1) in the lab portfolio. I also started on 2.7.2. So far, the labs in the labportfolio are far better written than the ones in the self-study guide.
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(3) EIGRP – Note taking

Alright, I am done with reading about EIGRP. I am now skimming through the chapter, and taking notes. I have an okay understanding of how EIGRP works, and I am looking forward to the labs to nail out unknowns. I am not 100% convinced about taking notes, or rather doing it in the order im doing (reading first, then skimming and taking notes, then going to the lab).
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(3) EIGRP Reading

Chapter 3, EIGRP. Started reading about the inner workings of EIGRP today. EIGRP is an improved distance vector protocol provided by Cisco themselves. It is an improved distance vector protocol, because it passes updates directly to its neighbours. It is more advanced than traditional distance vector protocols, because it supports VLSM and it does not use periodic updates.
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iPhone + dent

I watched an iPhone get a dent yesterday. Not a pretty sight. It was my girlfriends iPhone. She dropped it on the floor, and unfortunally it landed on the edge of a doorstep, causing it to get a dent. Nothing wrong with the glass surface or function of the phone at all.
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I was right.

There was no Internet connection at my second hotel, that actually worked. I really do think its a necessity to have a good and reliable Internet connection for your visitors. Watching TV and reading books used to be what you could do in a hotel-room, now however, the Internet is the main source of information for many people, so why not give your hotel an edge and use it as a selling point?
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