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Pop Quiz - Spanning-Tree Protocol

Fri, 2011-07-29 00:09

Here is another pop quiz for another Friday:

1. What is the 802.1d spanning-tree port role for every port on a root bridge?
A) Root
B) Blocking
C) Designated
D) Nondesignated

2. Every switch running IEEE 802.1d spanning-tree protocol has a Bridge ID (BID). How is the BID derived?
A) The BID is the base MAC address.
B) The BID is created from a bridge priority value, optionally an extended system ID, and the switch's base MAC address.
C) It is a random number generated based on when the switch is powered on.

3. Select the correct steps that a port goes through when transitioning to forwarding when using IEEE 802.1d:
A) Forwarding, Blocking, Listening, Learning
B) Blocking, Forwarding, Listening, Learning
C) Blocking, Learning, Listening, Forwarding
D) Blocking, Listening, Learning, Forwarding

Answers below...

Privacy Concerns with Google Plus

Wed, 2011-07-27 07:25

An interesting write-up over at Network World caught my eye today about the lack of privacy some people experienced when using Google+. Julie Bort, a journalist over at Network World, frequently writes for their Microsoft Subnet community.

Julie describes a not uncommon experience of an average user with privacy concerns trying to use the new social media offering from Google. Trying to keep certain information out of the public eye apparently isn't as easy as it use to be.

Anyone have a similar experience with Google+ yet?

CCNA Voice Official Cert Guide

Sun, 2011-07-24 21:43

Coming soon to a bookstore, web browser shopping cart, or a shelf near you - the CCNA Voice 640-461 Official Cert Guide.

Authored by Jeremy Cioara and Michael Valentine, this book covers the basics of implementing Cisco Voice over IP solutions. Contents include:

  • Basics on VOIP and Unified Communications
  • Managing Endpoints and End Users
  • Handling Calls
  • Telephony Features
  • Voicemail
  • Troubleshooting

App of the Week - SoundHound

Wed, 2011-07-20 18:01

If you have an iPhone or other smart phone, you have got to check out SoundHound. It is an app that can "listen" to nearly any song that is playing and figure out what it is. This is handy if you are in a store or restaurant and want to know the name of the song or artist that is playing.  I've found this one works the best compared other similar functioning apps.

The new 4.0 version was released today and it now includes real time lyrics for over 500,000 songs! This means nearly any song that is playing in the app, it can show you the lyrics while the song is playing and follow along. This is icing on the cake for an already awesome app - and the cost? Totally free!

Stop Rogue DHCP Servers with DHCP Snooping

Wed, 2011-07-20 00:02

Protecting your network can be a daunting task. There are so many attack vectors to keep an eye on;  it is literally a full time job (and a certification track) to learn how to thwart evil doers. So, today we're going to take a look at one of those attack vectors - man in the middle using a rogue DHCP server. Then we're going to focus on how to stop those attacks dead in their tracks. 

Cisco to Layoff 6500 Employees

Mon, 2011-07-18 18:51

Cisco announced today that it will be laying off 6,500 employees as part of the "comprehensive action plan" to rightsize the company. 

According to the press release, this includes 2,100 employees who chose to participate in an early retirement program. This includes a reduction of 15 percent of their VP and higher executive level employees. 

This process will cost Cisco about $1.3 Billion USD in severance fees and other payments. Hopefully for shareholders it will yield some cost savings and help the company make a turn in the right direction. 

In addition to the 6,500 employees, a set-top box manufacturing plant in Mexico will be sold to Foxconn Technology Group (the same group that makes iPhones and other electronics). This equates to 5,000 additional employees being shed from Cisco's payroll (and shifted to Foxconn's payroll) effective FQ1 2012.

John Chamber's Keynote from Cisco Live 2011

Sat, 2011-07-16 09:07

If you missed Chamber's keynote earlier this week, here it is:

Customer Appreciation Event

Thu, 2011-07-14 10:56

Customer Appreciation Event was pretty good! The food, music, and hats were all good. The chill room with the video games was a nice feature. The performers were doin their thing out on the pool - one word to describe that is "interesting."

Train was the headliner band. I got a video of them performing Hey Soul Sister, check it out below. Overall it was a good time. Thanks Cisco :-)

Updated Cisco Small Business Design Guides

Thu, 2011-07-14 08:13

I love these things...putting the link just so I can delete the email and find this again. Ahhhh...zero items in the inbox...that'll last for 5.83 seconds...

http://www.cisco.com/web/partners/sell/smb/tools_and_resources/secure_network_foundation_2.html

How to Prepare for the CCNP TSHOOT Exam

Wed, 2011-07-13 23:34
I attended the TSHOOT prep session today at Cisco Live. Here are the notes I took and some snippets from the presentation. Sorry if this is a bit disjointed, that was the nature of the presentation.

What does the TSHOOT exam cover?

Cisco Network Emergency Response Vehicle (NERV)

Wed, 2011-07-13 16:26
Cisco Live NERV 1

If you have never been inside of the NERV Truck, you've got to check it out. The truck itself is actually a production ready vehicle that responds to real disasters where communications have been knocked out. 

According to the woman I spoke with today in the truck, Cisco deploys the truck as a public service to assist public safety officials and rescue personnel after disasters strike an area hard enough to take local communication systems down. The truck is equipped with a conference room and enough cameras and phones to support several conversations at the same time. 

Connectivity is provided via a satellite uplink and the specific provider is negotiated based on the area that the truck is being deployed. 

Check out the video and the link below for more information.

Routing issue affecting conference Internet access

Wed, 2011-07-13 14:21

If you are attending the conference and have been having issues with accessing certain websites (including tekcert.com) from the conference wifi, the problem has been resolved. I stopped by the NOC and spoke with Doug, a spokesman for the NOC to get more information. Here's what I learned:

What was the problem? 

There was a router with a failing interface somewhere on the east coast in the provider's network. This was causing a routing loop effectively DOSing traffic.

The problem seemed to be intermittent. How is Cisco Live getting Internet connectivity?

The Internet connectivity here at Cisco Live is being provided via Qwest / Century Link. There are two connections going in different locations. The reason the problem was affecting some destinations and not others was based on the destination IP and where it was being routed out.

Cisco Live 2011 Network Topology

Wed, 2011-07-13 12:48
Cisco Live 2011 Network Topology

If you've ever wondered what the network topology of a large conference looks like, check out the attached image. Cisco has displayed the topology of the Cisco Live network just outside the NOC on some screens. 

Pretty simple setup, but solid design for sure. Providing wireless for 15,000+ attendees is no small task!

Securing DNS

Tue, 2011-07-12 12:38
Attended the Securing DNS session this morning and learned a couple new things. I took notes through the session which I'll share below.
There are a couple types of attacks that are out in the wild and script kiddie tools have been written to use these. If you manage the DNS servers for your organization, you should definitely take steps to protect your stuff.
The two main attacks that were reviewed are:

Cisco Live World of Solutions

Mon, 2011-07-11 19:23
Cisco Live WoS 1

Quite an impressive display this year in the World of Solutions! There are so many vendors and so little time, I don't know how I can make it around to each one. In my free time between sessions this week, I will be headed here to get one-on-one info from as many companies as I can. 

If you want more information about specific vendor or product, feel free to comment below and I'll see what I can do!

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