RawCode

In a broad scope, there is two steps to Proper QoS implementation. Tagging and Policy.

Tagging – Tagging allows you to classify the various flows of traffic on your network. The are many different criteria on which a flow can be classified. IP address, TCP ports, Session based information (telnet, ssh, http, ftp), even URLs. Once a flow has been classified, it is handled in accordance of how your policy dictates. Note that the classes are arbitary and only serve to idenitify the various flows in the network.

Policy – Your policy will define how to handle the classified traffic. Which class does it drop first once congestion is encountered? Which classes get prefrerental or expididted treatment over other classes? Which class receives less than best effort handling? What applications are “mission critical”? In a large company, they might have over 3000 different apps on the network. Put too many in the mission critical catergory and the classification is no longer mission critical. This will be the hardest task of implementing QoS. The technical stuff is easy compared to writing up a policy on what to drop first.

For actual configuration of QoS, I suggest End-to-End QoS Network Design : Quality of Service in LANs, WANs, and VPNs or just Cisco Solution Reference Network Designs.

Filed by RawCode at 3:35 am under Cisco, Networking
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I have been going to our monthly local Cisco Users group meetings the past two months. In the June meeting we covered what our goals would be for the group. The decided on topics of discussion and how we want to organize the group. ( We use yahoo groups. yay. :/ ) And I won a Cisco Pix which I sold on arstechnica to a guy for 300 bucks since I already had such a device in my possession. So far the meeting has been of great value to me.

So this past Wednesday I went to our monthly local Cisco User’s group meeting. Our topic this time was QoS (Quality of service). The presentation basically covered how to properly structure a QoS implementation. QoS allows the network to guarantee a specific level of network quality so it can be used for various solutions. VoIP is an example of such a solution. It does this by queuing and selective packet handling, weather it be dropping or expediting the packet through the network.

The presentation was given by Tim Szigeti from Cisco Systems. Tim Szigeti is the technical lead engineer for Cisco’s QoS development. In other words he is THE MAN when it comes to QoS. I was amazed to find that a man of such knowledge would come to Alaska to talk about QoS. I was starstruck. *big dumb grin*

Anyways the presentation was very good. At about two hours long, we were not able to get into the technical discussion of configuring QoS. However we did get a very good introduction into QoS, what it offers, and how to plan for implemention. Once of the points was how NBAR ( Network Based application recognition) could be used to classify traffic for QoS purposes. I asked ” Does NBAR run in hardware along side CEF or does it run at the process level consuming cpu resources?” He said it was a very good question and went on to explain that using NBAR uses CEF to examine only the first packet of a flow. Hence it is rather efficient.

He stated that normally for the first good question during a presentation he awards a book, but he didn’t lug any along this time. So after the presentation, I emailed him asking about the book and that I would pay for shipping if I had to. He wrote back asking for my address and justed ordered one off amazon for me! Tim Rules!

Turns out that he is one of the authors of the book: End-to-End QoS Network Design : Quality of Service in LANs, WANs, and VPNs

So after the presentation we chatted for half an hour about QoS and various other questions I had. After awhile he asked if I was a CCIE… *He actually thought I had the stuff to be a CCIE* ( Or he was just being nice… but whatever, I don’t care!) And I said no, only a CCNA working on my CCDA. I am just starstruck!

Anyways great presentation by Tim Szigeti and thanks to Cisco from holding the users group.

Filed by RawCode at 3:25 am under Networking
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I have seen this argument multiple times on different forums. Someone has a high speed link, and they are complaining that it is slow. Here is a little Q and A from one of the forums.

Pulled from ArsT: http://episteme.arstechnica.com/eve/ubb.x/a/tpc/f/469092836/m/888007862731/r/487004172731#487004172731

neosci

Ok, I was able to do an iperf test. Here are the results:

This is plain ole’ iperf -c ip, with the server listening at by iperf -s
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 7.52 MBytes 6.27 Mbits/sec
[root@chicagofw /]#


Now I do iperf -c ip -P 10, for 10 connections:

[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.1 sec 4.95 MBytes 4.12 Mbits/sec
[ 5] 0.0-10.1 sec 4.93 MBytes 4.11 Mbits/sec
[ 11] 0.0-10.1 sec 4.86 MBytes 4.05 Mbits/sec
[ 10] 0.0-10.1 sec 4.88 MBytes 4.07 Mbits/sec
[ 9] 0.0-10.1 sec 4.92 MBytes 4.10 Mbits/sec
[ 7] 0.0-10.1 sec 4.93 MBytes 4.11 Mbits/sec
[ 4] 0.0-10.1 sec 4.95 MBytes 4.12 Mbits/sec
[ 8] 0.0-10.1 sec 4.92 MBytes 4.10 Mbits/sec
[ 12] 0.0-10.1 sec 4.84 MBytes 4.03 Mbits/sec
[ 6] 0.0-10.1 sec 4.92 MBytes 4.10 Mbits/sec
[SUM] 0.0-10.1 sec 49.1 MBytes 40.9 Mbits/sec


So, unless I’m using iperf wrong… we ARE hitting our bandwidth with multiple connections… Why can’t we hit it with a single connection?? Is this normal with a DS3?

RawCode

Window Size, you are hitting the limitation of tcp ACKs and latency. You have to adjust window size in accordance with latency if you want a faster single connection.

http://rdweb.cns.vt.edu/public/notes/win2k-tcpip.htm

sryan2k1

Your saying a stock box can’t push more then 6Mb/Sec? I’m pretty sure my boxes at home can do lan transfers faster then that, nothing special

RawCode

Your are correct. Your box should, but tell me. What is your latency on your lan. Mine is .05msec or so.

Let say it is 1ms.
RTT = .001 seconds (1ms)
bandwidth = 100,000,000 bits (100 Mbit)

100,000,000 x 0.001 seconds = 100,000 bits, or 12.207KB for a window size. Which is roughly 27 1460 byte segments. Windows default window size is more than capable to handle this.

Because of TCP being session based, it has to wait for an ACK for each window. The higher the latency, the more time the tcp stack has to wait for the ACK. Which then limits bandwidth.

Lets try something a bit more extreme.

RTT to the moon = 2.6 seconds
Bandwith = 45Mb (DS3)

so 45,000,000 x 2.6 =117,000,000 bits. Or about a 13.94 MegaByte windows size. Just to saturate a DS3 to the moon using TCP.

Time for a more realistic example.

My work offers 10Mb dsl in Alaska. RTT to dslreports speed test is 100ms. (in CA)

bandwidth = 10,000,000
RTT = 0.1 second

10,000,000 x .1 = 1000000 bits or 125,000 byte window size. Just to use a speedtest in CA to saturate a 10Mb line. Default window size on a windows box is 8192 bytes. This is why some customers call and complain about speed when they do not understand how to test, nor how TCP actually works.

Refer to RFC 1323

Filed by RawCode at 7:46 am under Networking
1 Comment

RJ45 to DB25 Pinout

The table below lists the pins for the RJ-45 and MMOD. The colors listed are the typical wire colors in the shells.

RJ45 DB25
1 Blue 5
2 Orange 8
3 Black 3
4 Red 7
5 Green 7
6 Yellow 2
7 Brown 20
8 White 4


Filed by RawCode at 2:42 am under Cisco, Networking
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How to configure a USR Modem for dialin management access.

If you get yourself a USR Sportster, I have explicit instructions -step by step…
Cisco has a modem connection cable kit that works with a USR (has 25-pin connector vs your 9-pin)
(CCAB-25AS-MMOD=) Male DB-25 Modem Connector, **Cisco-equivalent $25.00

Attaching a US Robotics 33.6/56k Sportster modem to the Console Port of a Cisco Router (or PIX FW)

Follow these steps exactly to attach a modem to the console port for dial-in out-of-band management of the router:

1. Connect the modem to your PC’s open COM port (COM1 in this example) using the supplied 25-pin RJ45 adapter, rolled black or light blue cable, and 9-pin adapter.

2. Reset the modem to factory defaults. Set DIP Switch 7 to the down position and turn on the modem. Wait 10 seconds, turn the modem off. (Out of the box, 3, 5, and 8 are down, all others are up).

3. Set Modem DIP Switches 1, 3 and 8 down, all others up. Turn the modem back on.

4. Open HyperTerminal session direct to COM1.

5. Type AT . You should see “OK”.

6. Type ATI4 to view the current modem settings:

U.S. Robotics 33600 Fax Settings…
B0 E1 F1 M1 Q0 V1 X4 Y0 BAUD=9600 PARITY=N WORDLEN=8 DIAL=TONE ON HOOK CID=0 &A3 &B1 &C1 &D0 &G0 &H1 &I0 &K1 &M4 &N0 &P0 &R2 &S0 &T5 &U0 &Y1 S00=001 S01=000 S02=043 S03=013 S04=010 S05=008 S06=002
S07=060 S08=002 S09=006 S10=014 S11=070 S12=050 S13=000
S15=000 S16=000 S18=000 S19=000 S21=010 S22=017 S23=019
S25=005 S27=000 S28=008 S29=020 S30=000 S31=128 S32=002
S33=000 S34=000 S35=000 S36=014 S38=000 S39=000 S40=001
S41=000 S42=000

LAST DIALED #:

7. Enter this command string exactly (cut and paste):
ATE0F1Q1&I0&H0&K0&A0&B1&N6&C1&D0&W0

8. Type ATI4 again, this time you will not see it echoed back to the screen. When you hit you should see this:
U.S. Robotics 33600 Fax Settings… B0 E0 F1 M1 Q1 V1 X4 Y0 BAUD=9600 PARITY=N WORDLEN=8 DIAL=TONE ON HOOK CID=0 &A0 &B1 &C1 &D0 &G0 &H0 &I0 &K0 &M4 &N6 &P0 &R2 &S0 &T5 &U0 &Y1

S00=001 S01=000 S02=043 S03=013 S04=010 S05=008 S06=002
S07=060 S08=002 S09=006 S10=014 S11=070 S12=050 S13=000
S15=000 S16=000 S18=000 S19=000 S21=010 S22=017 S23=019
S25=005 S27=000 S28=008 S29=020 S30=000 S31=128 S32=002
S33=000 S34=000 S35=000 S36=014 S38=000 S39=000 S40=001
S41=000 S42=000

LAST DIALED #:

9. Now turn the modem off. Set DIP switches 1, 4 and 8 down, all others up (put 3 up, bring 4 down).

10. Turn the modem back on, type ATI4 again to verify that the configuration has remained correct.

11. Power on the Cisco router, wait full 2 minutes before plugging the rollover cable into the console port.

12. Plug the rollover cable into the console port of the router.

13. Power on the Modem.

14. Using HyperTerminal, dial the modem’s phone number.

15. Once you are connected, you may not get a response for up to 20-30 seconds. Be patient young Jedi. Hit a couple of times and you should get a router> prompt.

16. If you get connected, and see a rommon 1> prompt, the modem was probably plugged into the router too early. Simply type reset, confirm the reload and watch the router re-load the OS and then you should see the router> prompt.

I’ve done this hundreds of times and it always works.

Filed by RawCode at 2:37 am under Cisco, Networking
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After getting on with ING Direct to keep money for emergencies, I have been trying to find other places to keep cash that will still be accessable when needed. Not accessable to the point of a savings account at ING, but not stocks either.

I have been looking at setting up a CD ladder. That way I would have some amount of money maturing every year for the next five years while taking advantage of better rates. At ING there is a early withdrawl penalty of three months interest for one year cds and six months interest for longer term cds. But you have access to your money when you need it after waiting for it to be transfered. Good way to keep a large majority of an emergency fund somewhat accessable while earning more interest than just a savings account.

I have also been looking at I-bonds at TreasuryDirect. This is a longer term investment as once you invest, you cannot touch it for twelve months. If you withdraw before five years, you are penalized three months worth of interest. The rate is adjusted every six months according to inflation, currently it is a 4.8% which is better than 5 year cd’s. A pretty safe, medium term investment. Good for saving up for a new car or a down payment on a new house.

Both are good safe investments, but one does provide more access to your money when you need it.

Filed by RawCode at 2:50 am under Emergency Fund, Investing
3 Comments

One of our ferrets, “Peanut” might be put to sleep today.

He was diagnosed with Insulinoma about four months ago, so he is constantly on the verge of being hypoglycemic. He have been feeding him High calorie/protein cat food and giving him 1ml of a steroid twice a day to help combat it.

Four months ago, we found him having seizures. We rushed him to the local Vet ER to get him checked on. After they did a blood test they found that his blood sugar level was not even detectable on their test. Once given high calorie sugar laden tube snacks he stabilized. However he lost his eyesight, and some mobility in his legs. The vet having seen this before stated that she has seen ferrets regain eyesight and mobility after being treated by steroids and high calorie food. Might take a few months however.

Well it has been a few months, and he is still blind and has really stiff rear legs. He cannot walk on them correctly, so the rub in the wrong places when he walks around blindly. It has caused a cut on his foot which is now infected. We have to give him baths all the time since he cannot find the litter box reliably, and we have to put him in front of the food during feeing time. I have NEVER seen such a small animal eat soo much food before. Two heaping tablespoons of this stuff gone each time, twice a day. And it is barely enough to maintain him.

And as I was getting ready for work, is when she found the infection. She started crying saying, “He isn’t going to get better is he? He is just getting worse and worse.” I just held her, and apologized. “It makes me so sad to see him like this. I know that insulinoma is fatal for all ferrets, but I didn’t think it would be so soon.” I just apologized some more, and kept on holding her close.

We really hoped he would recover.

I really hoped he would recover even if it was just for her piece of mind.

So this morning, I might be giving Peanut his last amount of meds and a whole bunch of food. And then bathing him after that to get him all nice and clean for the trip to the vet in his little polar fleece ferret pouch. I will post pics once I get home.

Peanut (left) fending off an assult from Sly (right):

Peanut (left) and sly (right) playing in the liiter box:

Peanut being tortured:

Happer times, Sly (left), Misty (center) and Peanut (right) playing:

Filed by RawCode at 4:32 am under Commentary
1 Comment

I have been on a book buying spree as of late. Mostly technical reference, but some pleasure. This one stands out the most of my recently read novels.

It is about a fictional nation called totalitarian Republic of Greater East Asia which holds an annual program nicknamed “Battle Royale”. In this program, each year a 9th grade class of 42 students is selected at random to enter the program. Once the class is selected, the entire class is deported to a remote location from where they cannot escape. They all are given a rucksack which contains food, water, and a weapon of some kind. The Program will end once there is a single student left alive.

Honestly, I was quite skepitcal of such a premise in a novel. It sounds cheap, poorly written and just a bad idea overall. In actuality, it is a very good novel. It was just like watching a trainwreck in slow motion. You disliked what you saw and read. You were horrified at what was happening to the characters. But you wanted to see who had the ability to survive. It makes you think about what you would do in a situation like theirs. Who could you trust in your group of friends? Who would you give a weapon to cover your back? Do you really know them at that level?

Trying to keep track of 42 different characters in a novel would be defining tedium. However the author does a great job of weaving into the story what defines the characters strengths, weaknesses, and general behavior. Every single character is memorable in some fashion that you will not forget them once you reach the conclusion.

I HIGHLY suggest the book.

Filed by RawCode at 2:51 am under Commentary
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According to a test on OKCupid, I am the Simple geek. I perfer to think of it as a geek with social grace and style. Yeah thats it.

The Simple Geek You answered 75% of the questions as a geek truly would.

You don’t seem to sway in either direction, however you still seem to have some latent geek attributes within you. Maybe you’re interested in computers but not a gamer? Maybe you’ve got geek hobbies but none of the awkward social tendencies. You may be slightly geekier than you thought and in denial! The simple geek usually has various quirks that friends may make fun of, but in general can be considered a fairly normal person. Your geek attributes make you less likely to conform to society. The popular kids don’t hate you but the geeks don’t either, so it’s a respectable demographic. In a nutshell, you answered enough questions with geek tendencies and enough questions without geek tendencies that it’s difficult to pinpoint your exact alignment.

Filed by RawCode at 1:40 am under Banter
2 Comments

This summer I have riding my Mountain Bike like a mad man. Around 50 miles a week on good weeks. I ride a Giant Warp Full Suspension, which isn’t the lightest thing ever. But who cares about weight when you are not racing.

I have also recently joined a local health club and have started swimming in one hour blocks. Great stuff. My shoulders are currently very sore as are my calfs.

Before this summer, when I went to a friends wedding, I weighed around 210 lbs. I am currently down to 176lbs and still dropping. I have not really modified my diet much. I drink diet sodas when I want, and eat fast food every other day out of convenience. Eat a can of fruit @ lunch. Normally pineapple for da’ ladies

Hopefully once winter hits, I will keep hitting the gym. My friends keep telling me I lost ALOT of weight, which sure does feel good. I gained all the weight during a bad breakup back in 2001 in the middle of winter. And I just never took the time nor the effort to get it worked off.

I am sure glad I did.

Filed by RawCode at 7:17 am under Banter
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