Friday, February 15, 2008

Using Cisco SDM in GNS3

One of the great things about GNS3 is that you can practice your labs using real IOS images. The same goes for Cisco SDM. Tasks such as configuring GRE over IPSec tunnels or applying IOS Firewall can be made so much easier via the Cisco SDM.

In this entry I'm going to show you how I configured my laptop to access the Cisco SDM within my GNS3 lab.

This lab assumes you are using a Windows XP system, you use IE, and your Java version is  jre-1_5_0_09-windows-i586-p.exe (other versions of JRE may be fine but this is what works for me).

1) Configure a loopback interface on your laptop.
The first task is to configure a loopback interface. To do this go to:
  • Start - Settings - Control Panel - Add Hardware
  • Select Next when the wizard starts and then 'Yes, I have already connected the hardware', select Next
  • You are presented with a list of currently installed devices, scroll to the bottom and choose 'Add a new hardware device', select Next
  • Check the button for 'Intsall the hardware that I manually select from a list' and select Next
  • Select 'Network Adapters' and then select Next
  • On the next screen choose 'Microsoft' from the left column and then 'Microsoft Loopback Adapter' from the right column, select Next and then Next again to install.
2)  Create your lab
Build your lab and make sure that you install an FE-TX interface on the router/firewall you'd like the laptop to connect to. Save the lab and close it.

3) Make a note of the Loopback hardware address
Go to the directory for GNS e.g.) C:\Program Files\GNS3 and locate the file 'Network device list.cmd'
Run this and make a note of the output for the new loopback address you set up in point 1 e.g)
NIO_gen_eth:\Device\NPF_{19DB09AF-0DC2-43C6-B9B7-69A0E722FA45}
 Name      : Local Area Connection 2
Desciption: Microsoft Loopback driver
N.B - copy the equivilent output that I've marked in Bold

4) Insert the output for your Loopback interface in to your lab
  • Navigate to the saved location for your lab and and right click on the file e.g) mylab.net then select edit network file (if prompted for an application choose Notepad).
  • Locate the device you wish to add your Loopback connection to and insert the interface address like the example below:  [[ROUTER R3]]
            model = 3620
            console = 2003
            slot0 = NM-4T
            s0/0 = R2 s0/1
            slot1 = NM-1FE-TX
            f1/0 = NIO_gen_eth:\Device\NPF_{19DB09AF-0DC2-43C6-B9B7-69A0E722FA45}
            x = 108.0
            y = 19.0
  • Save this.
5) Open GNS3 and open the Lab you have just added your loopback interface. 
  • If correctly configured you should now see a cloud marked something like C0 or C1 connecting to your FE interface on the router you choose to assign the connection to.
  •  Assign IP addresses on the same subnet to both the loopback interface on your windows XP system and the FE-TX interface on your network device.
  • Ping the IP addresses from either side and you should have connectivity. If you don't, trouble shoot accordingly

Now you have a functioning connection into your lab you can do many things. For example download and install Cisco SDM launcher for PC and then enter the internal IP address for the router in your lab you'd like to connect to.


You can also set up a syslog server. Install Kiwi Syslog Server and then configure your network devices to send logging information to the IP address assigned to your loopback interface.


You might want to install a RADIUS server on your XP system and then foward all RADIUS authentication requests to your loop back adapter.


These are just some examples of what you can do once you have your Loopback configure. Enjoy!

 

Monday, January 28, 2008

DOCSIS - Data-Over-Cable-Service-Interface-Specification

DOCSIS - Standard certification of cable equipment vendor devices

Sets out the physical and MAC layer standards

Defines RF interface requirements over data systems

Equipment must pass certification by CableLabs, Texas instruments, Netgear, Motorola (et al).

In Europe, EuroDOCSIS is the standard

Physical Specs include channel widths and modulation

MAC Layer specs include Access Method (e.g. TDM or Synchronos Code Division Multiplex Access)

Links :
DOSCIS on Wikipedia
DOCSIS.org
Cisco ITH - Cable Technologies

Sunday, January 27, 2008

Cisco CCNP - TSHOOT 642-832 study materials

Here are links to the study materials for the new Cisco CCNP TSHOOT 642-832 exam:

Cisco CCNP TSHOOT 642-832 Offiicial Certification Guide - Click here
Cisco CCNP TSHOOT 642-832 Cert Kit - Click here
Cisco CCNP TSHOOT 642-832 Cert Flash Cards Online - Click here
Cisco CCNP TSHOOT 642-832 Quick Reference (Coming Soon) - Click here

Cisco CCNP - SWITCH 642-813 study materials

Here is a list of study matierials available for the Cisco CCNP SWITCH 642-813 exam:

Cisco CCNP SWITCH 642-813 Offical Certification Guide - Click here
Cisco CCNP SWITCH 642-813 Cert Kit - Click here
Cisco CCNP SWITCH 642-813 Cert Flash Cards Online - Click here
Cisco CCNP SWITCH 642-813 Portable Command Guide (Coming Soon) - Click here
Cisco CCNP SWITCH 642-813  Quick Reference (Coming Soon) - Click here

Cisco CCNP - ROUTE 642-902 Study materials

Here is a list of Cisco CCNP ROUTE Study materials, presently only available from Cisco Press.

Cisco CCNP ROUTE 642-902 Official Certification Guide - Click here
Cisco CCNP ROUTE 642-902 Cert Kit - Click here
Cisco CCNP ROUTE 642-902 Flash cards online - Click here
Cisco CCNP ROUTE 642-902 Portable Command Guide (Coming Soon) - Click here
Cisco CCNP ROUTE 642-902 Quick Reference Guide (Coming Soon) - Click here

CCNP Revised track

Here it is folks! -https://learningnetwork.cisco.com/docs/DOC-6393

Cisco have announced the new structure for the CCNP and on first glance it looks good.

Reduced from 4 exams to 3, with each one 2 hours long (up from 90 minutes) the emphasis has shifted to more real world application of the subjects including design, deployment, verification and troubleshooting of the subject matter. Expect there to be more configuration type questions on the exam.

If you're like me and are unsure how the new exams affect your studies you can use the Exam Configuration tool -http://www.cisco.com/web/learning/le3/le2/le37/le10/ccnp_exam_combo_tool.html - work out how best to proceed.

For me, I'm taking my ISCW on Friday and am scheduled to start the  BSCI in Feb. So long as I pass the exam first time I think my track will be : BSCI + SWITCH + TSHOOT

So that'll still be 4 exams for me but what you gonna do when the firm is paying :o)

All the best with your studies!

Saturday, January 5, 2008

ADSL Coding Techniques

ADSL has a number of coding techniques:
i) Single Carrier - uses Carrierless Amplitude and Phase Modulation (CAP) - Proprietary
ii) Multiple Carrier - uses Discreet MultiTone Modulation (DMT) - Multiple Carrier Standard
iii) Multiple Carrie with G.lite - uses slower speeds but doesn't require the signals to be split at the subscriber end. Most popular method for mass market.

ADSL Data Rates

ADLS data rates as follows:
Downstream-
ADSL = 8Mbps for 18,000ft
ADSL2= 12Mbps for 8,000ft
ADSL2+= 24Mbps for 5,000ft

Upstream-
1Mbps for upstream data requests.

Friday, January 4, 2008

DSL Distance Limits

DSL                       Max Data Rate       Distance (Feet/KM)
ADSL                    8M/1M                   18,000/5.5
VDSL                    52M/13M               4,500/1.4
IDSL                     144k/144k              18,000/5.5
SDSL                    768k/768k              22,000/6.7
G.SHDSL             2.3M/2.3M             28,000/8.5

Factors that affect distance:
Signal Attenuation
Bridge Tap - an extra telephone wirte with an un-terminated cable end connected to the local loop, can cause noise, reflection, raqdiate power to reduce signals and therefore speed
Local Coils - Wrap of excess wire along the local loop
Wire Gauage - thickness of wire, high speeds use thick wire
Impodence Mismatch - noise/echo on the line
Crosstalk - interference
AM Radio interference
Fibre Optics - ADSL signals cannot pass thorugh the conversion from Analog to Digital to Analog that occurs if a portion of the telephone circuit traverses fibre.

DSL Variants

DSL Differs in:
i) Nature - Is it Symmetrical or Asymmetrical?
ii) Max Data Rate - i.e. max speed deployed
iii) Live Coding Technology - technique used to deploy signall to copper wire
iv) Data/Voice Support - Certain DSL types do not support both data and voice at the same time
v) Max Distance - Distance DSL signals can span

DSL            Nature              Max Rate               Data+POTS
ADSL         ASym              8m/1m                     Yes
RADSL      ASym              Adaptable                Yes
VDSL         Both                52m/13m                 Yes
IDSL          Sym                 144k/144k               No
SDSL         Sym                 768k/768k               No
HDSL        Sym                 2M/2M                    No
G.SHDSL  Sym                 2.3M/2.3M              No