Saturday, 15 May 2010


Ok well here it is a shameless plea for help.

I am obviously interested in wireless and will be targeting CCIE next year so I need to improve my lab.

Is there anyone out there with a Cisco AIR-WLC4402-12-K9 that is just gathering dust. Now donating it would be great but I have some funds to purchase but they are all a bit pricey on eBay.

Equally any other wireless hardware that people want to donate to a good home will be appreciated and loved.

Key things I have to get are a spectrum analyser, looking at actually getting a WiSpy usb, also any spare access points considered.

All enquiries or offers can be emailed diect to me at

There has to be someone out there with a low cost 4402?

Google Boobs again!!!!!!

Well well well who would have thought it!

Google after many accusations of spying, infringing peoples privacy and controversy over mapping wi-fi networks with their Street View program have come clean and admitted collecting information sent over wireless networks.

Well I personally think that they now have a lot to answer for, after all its quite difficult to do accidentally, mapping wi-fi networks would be an entirely different process than authenticating to the networks and downloading data. In my view its at the very least very poor project management and obviously a complete lack of knowledge about what they were doing, at the worst its spying and theft of data.

To turn around after three years and say we didn't know well I'm sorry Google I don't believe you. You have been caught with your pants down, hand in the cookie jar, however you want to call it.

I doubt it will go legal but who the hell is monitoring these people.

Read more here

Wi-fi owner fined for lax security in Germany

Well it looks like big brother is clamping down, the unfortunate owner of a wi-fi network in Germany has been fined €100 by a German court because his network was not secured and a third party downloaded copyright material from it.

Personally as its a technical product and not everyone is tech savvy I feel it should be the service provider or the manufacturer that has the responsibility to ensure adequate security to meet legal obligations for domestic products ie anything sold to the public or provided as part of their broadband service. I know most service providers routers are secured these days but it doesn't go far enough with the compromises that are out there. Enterprise products are entirely different as you expect them to be installed by a technically competent person.

Read more here

Thursday, 13 May 2010

Free Books

Where do I start, lets just say I am very suprised by Pearson Education.

You see they have a book review program and I got to find out about it and asked if I could review a few books that were coming out hoping I could get a seaky peak at a few wireless books as there are some new ones out this year.

Well I got an eamail with a list of books, non wireless but certainly a few that I was interested in. I replied to them saying which books I was genuinely very interested in and a week or so later took delivery.

Awesome scheme.

I spend quite a lot on books, study materials, hardware and exams so was really impressed.

Well as I said after a little email ping pong I now have a copy of "Securing the Bordeless Network" by Tom Gillis.

Initial thoughts are it looks good and I will certainly learn a few things but I have to review it so I am busily reading through it.

But hey, what a great scheme.

Tuesday, 11 May 2010

WLC Discovery Process

The LWAPP or from code version 5.2 CAPWAP discovery processes vary slightly

The general process is as follows

1 Layer 2 broadcast which isnt much use as it was only supported on the 1000 series access points.

2 Layer 3 broadcast

As this is blocked by the router and the IP helper-address only forwards directed broadcasts, unicasts and 8 UDP ports by default. These are TFTP port 69, DNS port 53, time protocol port 37, netbios name server port 137, netbios datagram server port 138, BOOTP client and server ports 67 and 68, TACACS service port 49.

Therefore you need to explicitly allow prt 12223 LWAPP data protocol and or port 5247 CAPWAP data protocol

Router(config)#interface fa y
Router(config-if)#ip helper-address x.x.x.x
Router(config)ip forward-protocol udp 12223

3 OTAP which should only be used in commissioning as it is/was a security risk now deprecated it was part of the RRM. It is now deprecated since code 6.0 and RRM is encrypted.

4 Locally stored controller IP address

5 DHCP option 43 is used to return the WLC IP address and is vendor specific. This is the IOS command for option 43

ip dhcp pool

Option 43 hex

DHCP can be set on the switch,router or via a DHCP server.

Along with option 43 you can have option 60 which is the vendor class identifier and says only return option 43 if you are sending an ip address to a client that needs it like an access point and loooks like this in IOS.

option 60 ascii "VCI string of the AP"

This shouldn't matter in an enterprise as your aps should be on their own subnet however its handy as thats not always the case and it prevents clients getting uneccessary information.

Options 241 and 120 are not exactly options but sub options and define how the IP address is sent. for everything but the Cisco 1000 series this is 241 which is hex. For the 1000 series its 120 which is ASCII.

6 DNS , configure DNS to returm the controller IP address to a query for CISCO-LWAPP-CONTROLLER@localdomain, also if you are running code 5.2 or above it helps to use CISC-CAPWAP-CONTROLLER@localdomain.

Generally after priming access points I always implement DHCP option 43 and DNS in enterprise deployments as you pretty much know that th access points will home to a controlller when and if they upscale add or replace access points.

The reason for priming is that you can asign ap names, ip addresses and WLC addresses and designate where the access point is to be deployed rather than ending up with hundreds of access points pulling down ip addresses and not knowing where they are.

CWNP Winners

The good guys at CWNP have ben running a competition the last about 6-8 weeks with prizes of CWNP Self Study Kit, CWNP Study Guides and a 32GB iPad.
Well the competition is over and the results are in.

I managed to get drawn out of the hat for the iPad which is brilliant news, no excuses for not stuying now!! I also managed to win a CWNP Self Study Kit which will have to be the CWSP which has an exam voucher with a free retake should you fail. The voucher never expires but the free retake is valid as on offer till the and of August. With the iPad and the Study kit thats well over £500. Brilliant.

You can see the other prizes and who the prize winners were here on the CWNP Forums

Just leaves me to say thanks to CWNP and congratulations to all those that took part.

Aruba Networks buy Azalea Networks

Aruba today annonced the acquisition of Azalea Mesh Networks.

Use the link below to read the press release

Good Luck

I am just taking this opportunity to wish two people I know, hopefully they won't mind me calling them freinds, the very best of luck for their CCIE Labs which they are taking.

Both have been working extremely hard in their respective studies and I admire them both greatly. They both deserve it and I am sure they will be successful.

Gabriel Bryson is taking the CCIE Security Lab on Wednesday 12th May 2010 and Jennifer Huber is taking the CCIE Wireless Lab on Tbhursday 13th May 2010.

Good luch to you both.

Thursday, 6 May 2010

No more CCIE OEQs

Well it looks like the end of Cisco's controvertial OEQs which have been a part of the CCIE track for about a year.

Some of the CCIE tracks having them added recently and others still waiting. However the news is that they will be gone as of the 10th of May from the R&S and Voice tracks. Surely its only a matter of time before they go completely.

I haven't seen anything official yet but thats the rumour.

I think there is enough pressure without them for CCIE candidates. Imagine you pay $1400 for the chance to take the exam and can fail in the first 30 minutes on the OEQs.

The written should be weeding out those that aren't upto the exam.

The CCIE lab has always been about hands on, it's the 800lb gorilla of the tech exam world.

I know that those who have failed the OEQs but aced the configuration and troubleshooting may not get much flexibility from Cisco, I can't see them saying "Oh well OK so it was a bad idea here's your CCIE as you aced the config part" but thats life.

It was always wrong when Cisco introduced two classes of CCIE the haves and the have nots. That the 360 candidates got the waiver was the thin end of the wedge but hail hail it looks like common sense has prevailed and maybe just maybe for once Cisco has listened to the communnity and relented. There are a lot of good ideas in the Cisco community and most Cisco certification candidates do it the right way, study hard and put in the hours. To fail the CCIE on 4 or 5 questions would heart breaking.

Well done Cisco, good move.

No doubt there will be other tweaks to the exam with that half hour slot to fill but its definitely a good move.

Tuesday, 4 May 2010

Access Server Config

It may not appear to be the hardest thing in the world but as I said in a previous post when I had the NM-16A/S in the 2613 router it wasn't working, I had all sort of intermittent issus and evn reterminated a few of the octal cablle ends that took some time. After swapping the NM-16A/S to a 2610 all was well so I could configure the access server.

Its actually amazingly straight forward, here is the config.

Current configuration : 828 bytes
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
hostname TermSrv
no aaa new-model
resource policy
ip subnet-zero
ip cef
no ip dhcp use vrf connected
no ip ips deny-action ips-interface
ip host R1 2033
ip host R2 2034
ip host R3 2035
ip host R4 2036
ip host R5 2037
interface Loopback0
ip address
interface Ethernet0/0
no ip address
ip classless
no ip http server
no ip http secure-server
line con 0
exec-timeout 0 0
logging synchronous
line 33 40
no exec
transport input all
line 41 48
line aux 0
line vty 0 4
password cisco

Another issue I had was looking for ports 1-32 which are taken up by module 0 and I was plugging into module 1, I know, with the issues I was having and expecting the access server to work first time you panic and think there is an issue. Note that it is a 2610 and only has 1 module slot, I assume that module 0 is taken up by the WIC slots. However, you always learn more if it doesn't work as you expect first time than if it does work.

Nice Rack!!!!

Yeah thought that might get some attention!

Well here is a photo of my rack that will see me through my CCNP and beyond. Its nearly all my own gear and even though its in a nice Skeletek rack and to me looks great my better half won't let me have it in the lounge.

And here are my access points

Anyway here is the run down

3 x Cisco 2620XM routers each with a pair of WIC-1Ts installed
2 x Cisco 2610XM routers each with a single WIC-1T
1 x Cisco 2610 router with a single WIC-1T
1 x Cisco 2610 router with an NM-16A/S used as a terminal server
1 x Cisco 2613 router, yes it has a token ring port.
1 x Cisco 1841 router with a pair of WIC-2Ts, I need to buy cables.
2 x 2501
1 x 2522 FR switch
1 x 2521

3 x Cisco 3550 EMI switches
1 x Cisco 3560-8 EMI for poe for the access points.b

1 x Cisco 2006 WLC
3 x Cisco 1242AG access points
2 x Cisco 1230 access points
1 x Cisco 1131AG access point
1 x Cisco 1252 access point

1 x Dell GX620 4GB of RAM
1 x Dell Poweredge 1800 Dual Xeon 3.2GHz 4GB of RAM running VMWare ESXi4.0

Running in VMWare ESX4.0 I have a small test domain with Windows Server 2003 and 2008 to familiarise myself with IAS and NPS. I also run Cisco WCS and ACS.

Running in VMWare ESX3.5 I Cisco Guest NAC appliance and Cisco MSE.

What do I want to add? Well thats the $64000 question.

I am buying a Cisco WLC 4402 this week.

Another Cisco 1841 router would be nice.

There will be an ASA 5505 going in.

A pair of Cisco 3560 switches would be real nice.

Studying CCNP

I am one of those people who gets the most out of actually getting something to work, and usually breaking it in the process, then fixing it to develope an understanding.

Now I have the CCNP BSCI Lab Portfolio book and the new CCNP ROUTE book, my intention is to flash through a few labs and see where I get and then go back and start reading the concepts. I know this might sound a little strange but I am hoping I will understand some of the commands and start to see how each routing protocol interacts and build on a foundation.

For the ROUTE exam I have a lot to learn as I only know the basics of routing from CCNA and there will be an awful lot to learn, I have given myself about two months or so. The really scary part will be BGP as it looks huge. I have chosen the new path as it has dropped a few topics which I may pick up at a later date such as MPLS, QoS and Multicast, however thse are all subject matter for the CCIP, I just can't see myself doing that but MPLS is becoming more and more important.

As for the Switch exam I understand most of the concepts and have implemented quite a lot of the technologies, trunking, etherchannel, layer 3 switching, high availability, the majority I have experience of however it is all the variables that will pose the issues such as LACP and PAgP. Spanning tree and ACLs will need practicing alot.

TSHOOT should not be an issue if I have studied each topic extensively, or am I deluding myself, we shall see.

All of this while looking for a gew quick wins on the wireless side so I may be challenged over the summer and miss some important world cup fixtures.

I intend to work to the posted exam objectives which I have put into a matrix where I will score myself on my knowledge level, 0 being I do't even know what that means and 5 being I am an expert and know it cold. I will post the patrix on the site so if you want to see my progress you can check on it. At the start thee may be some errors where I think I know something and give myself a 3 and downgrade that but when its all 3-5 I will be taking the exam, also it will depend on my comfort at the cli.

Wish me luck!!

Monday, 3 May 2010

CWNA Study Guide Chapter 2 Radio Frequency Fundamentals Key Learning Points - Part 2


As RF waves travel they encounter various media tha affect them in different ways, these medi include air, water, trees, walls etc. Anything that the RF waves encounter may affect the way the waves behave.

These RF propogation behaviours inclued absorption, reflection, refraction, scattering, diffraction, free space path loss, multipath, attenuation and gain.

The way RF waves move, propogate, as it moves away from the antenna can vary dramatically depending on what is in its path.

Different materials, combinations of materials or events can have significantly different effects on a signals charcteristics.


Absorption is a fundamental property of RF waves, different media will absorb more or less RF and attenuate a signal to a greater or lesser degree. For example concrete walls will generally have a highe absorption tan glass therefore greater attenuation.


RF waves will bounce off, reflect from, surfaces that are smooth. If the object is larger than the wave itself the wave will reflect, therefore reflection is dependent on frequency. Different object reflect different wavelengths to different degrees. Filing cabinets, doors erc can reflect RF wave sin the Wi-Fi spectrum, the angle of reflection depends on the angle of incidence.

Reflection can degrade signal strength and cause signal attenuation and data corruption. Hardware strategies help to overcome overcome these problems with directional antennas or antenna diversity.

Multiple reflected signals cause an effect known as multipath. MIMO antenna technologies actually take advantage of multipah.


Two types of scattering may occur the first type has a lesser effect on the RF wave and is caused when the wave travels through a medium containing minute particles like fog. The second type is when an RF wave hits an uneven surface and is reflected in many directions, foliage and rocky terain may cause this type of scattering.


refraction occurs when an RF wave travels through mediums of different density that cause the direction of the wave to change. Generally this is encountered over long distance outdoor bridge links where water vapour and changes in air pressure and temmperature may cause this effect.

The k factor is a unit of refractivity index in long distance bridge links. A k factor of 1 means no bending, a k factor less tahn 1 represents a signal bending away from earth. Normal atmospheric conditions have a k factorof 4/3 wic is bending sligtly towards te earth.


This is where an RF wave bends around an object and should not be confused with refraction. This would typically be some kind of obstruction. A dead zone may exist immediately behing the obstruction known as an RF shadow.


Loss or attenuation is the decrease in amplitude or signal strength. Loss may occur on the wire due to impedance of the cable or in the air due to absorption and distance. Different materials have different absorption properties.

Loss and gain may be gauged by a relative measurement of the change in pwer called dB.


Free space path loss (FSPL) is the attenuation of the signal due to the natural phenomenon of the signal spreading out over a larger area as the signal moves farther away from the antenna. Loss in signal strength is logarithmic and not linear therefore a signals strength does not decrease as muchin subsequent segments of equal distance as in the segment.

A 2.4 GHz signal will attenuate by approximately 80dB in the first 100m from the antenna source and only 6dB in the second 100m from the antenna source.

FSPL = 36.6 + (20log10(ƒ)) + (20log10(D))

where FSPL=free space path loss, ƒ=frequency and D= distance in miles.

FSPL = 32.44 + (20log10(ƒ)) + (20log10(D))

where FSPL=free space path loss, ƒ=frequency and D= distance in kilometres.

This can be described as the 6dB rule in that for every doubling of the distance te in loss of amp;itude will be 6dB.


Multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths. Causes of multipat are scattering, refraction, difraction and reflection. Typically reflection is the main cause of multipath.

The reflected signals will arrive at the receiving antenna nanoseconds after the priniciple signal due to travelling further, this time difference is knwn as delay spread.

The results of multipath may either be good or bad. generally the results are destructive due to the differences in phase of the multiple paths. The combined signal may attenuate, amplify or be corrupted.

The four possible results of multipath are

Downfade is decreased signal strength caused when the received signal arrives at the receiver at the same time as the principle signal but are out of phase by between 121 and 179 degrees.

Upfade is increased signal strength caused when the received signal arrives at the receiver at the same time as the principle signal and is in phase or nearly phase. The phase differences are between 0 and 120 degrees. The received signal can never be stronger than the transmitted signal due to free space path loss.

Nulling is the complete cancellation of the signal caused when the received signal arrives at the receiver at the same time as the principle signal but are out of phase by 180 degrees.

Data corruption can occur due to the differences in time between the reflected signals and the principle signal. The delay spread time differential may cause overlapping and the receiver may have problems demodulating the signal.

Multipath may be problematic causing layer 2 retransmissions and negatively impacting the WLAN throughput.

Direction antennas and antenna diversity may help reduce multipath problems.


Gain is the increase in amplitude and there are two types of gain, active and passive.

Active gain is the use of an amplifier on the wire and generally requies an external power source.

Passive gain is the focussing of the RF signal by use of an antenna.


Frequency Domain Tool - spectrum analyser

Time Domain Tool - oscilloscope

Sunday, 2 May 2010

CWNP Exam Offer

The good guys at CWNP are offering free exam retakes if you should happen to fail your first attempt.

If you buy an exam voucher from CWNP for either the CWNT (PW0-070), CWNA (PW0-104) or the CWSP (PW0-204) and are unfortunate enough not to pass they will let you resit the exam for free between 1st May 2010 and 30th August 2010.

I've never been in the right place at the right time to take advantage of similar offers from other vendors and I don't know if CWNP have done this before but its a great idea especially with the cost of exams these days. Also generally if you don't manage to pass first time round you want to get straight back in the saddle and try agian, obviously after a little revision of those weak areas that prevented the pass in the first place.

As I am currently studying I will certainly take advantage and set my goals to have a crack at the exam before the end of August.

More details are available here

I think these offers are great as it gives you that little bit of peace of mind as well as investment protection as non of us like throwing money away and most of us are self funding certifications these days.

They also have some great deals on their certification packages at the present time so go along and check out the CWNP Store

Saturday, 1 May 2010


Well tomorrow I intend to start studying my CCNP, I have been trying to get a little bit done all week but have been quite busy in work.

I went up to my lab a few nights ago and decided to setup the access server just to be ready, unfortunately it took alot longer than I anticipated as the Cisco 2612 that I was intending to use with an NM-16A/S just didn't want to play properly. One minute I had a connection from the access server to a router next it was gone when I went to check the cable moved and I got connectivity so you naturally think faulty connector but there was no consistency, I cut one of the ends off the octal cable and remade it but it didn't fix the issue.

Finally I took the NM-16A/S out of the Cisco 2612 and put it in a Cisco 2610, cut and pasted the configuration into the cli and kerching!!! Everything worked sweet as can be. Wasted hours but learned a great deal about setting up access servers which is actually really easy. However I had wasted  too much tome and that was that.

I intend to go through the CCNP ROUTE book cover to cover and lab up as much as I can. I will also use some videos, Cisco PEC and I bought the CCNP BSCI Lab Portfolio.

I will be starting EIGRP tomorrow and as routing is my weakest area of the CCNP it will be a struggle to get my CCNP ROUTE. I know I can do it but its if I can do it as quickly as I want to so I can get on with wireless study.

This will obviously distract me from my wireless studies but I will fit some in during my CCNP R&S studies. However I am committed to getting the CWNA aswell in the next few months so it will all be fun.