MS Office is online now! Will it change Google Docs for better?

Disclaimer: I am a Linux programmer, user and evangelist. I use open office and MS Office for work related documentation. When I bought a PC for my home use, I was very reluctant to buy ms office for the personal use as it was too pricey. Office is more expensive than MS Win7 by almost 1.6x to 2x. So, I chose not to buy the MS Office.

The Google docs service is around for quite some time now. It is a useful tool for non-m$ users like me. I could open email attachments online convert one doc format to other. So, I do not need to spend money just to open my mail attachments.

But the usefulness stops there. I don't think anyone can do some serious 'office work' on Google docs. For example, how do you do simple function like 'save as'? You will have to do 'make a copy' of a doc. Then delete the prev copy. I feel it is just good enough for very basic document/spreadsheet editing.

Recently Google added realtime doc sharing which could probably compete with plethora of web meeting tools like teamviewer, cisco webex etc. This is probably one 'new' feature that got added in so long time.

Today, this news item drew my attention. If ms office is offered online, that will give good competition to g.docs. as a result it is reasonable to expect Google would spend more money on the project and get some useable software. So, welcome Microsoft...

How to Ratelimit Physical Port (L2)

If you have a LAN (PC or Network)and you want to restrict the amount of data rate the LAN receives/transmits, with tc (Traffic Control) command you can achieve this very easily. All you need is that you need to make sure entire traffic passes throug a Linux machine in Bridge configuration.

You might want to type in the following command at your terminal.

# tc qdisc add dev eth0 root tbf rate 0.5mbit burst 5kb latency 70ms minburst 1540

This implements a 512kbps 'pipe'. In other words, entire LAN segment shown in the diagram gets to share 512kbps.

This command also implements bucket size of 5KBytes.

Packets would wait for 70milli seconds before they get dropped.

Applications
1) This is useful in lab environments where a DUT is to be tested with restricted bandwidth. DUT could be a base station simulator or any other network element.
2) In case you want to simulate the congestion or choked bandwidth within LAN, this comes handy to simulate a smaller pipe.

Whats inside UTStarcom's BSNL Branded WA3002GA ADSL2+Router

I have a ADSL modem at my disposal at my office. I am going to test my learnings from my personal Broadcom Beetel router in my home.

This ADSL modem is supplied by BSNL. This device has got 4 LAN Ethernet ports and has a Wifi-AP built in. Wan side, it connects to a ADSL enabled POTS line.

I have logged into GUI. surprise surprise, I saw the exactly the same look and feel of my Airtel -supplied-beetel modem. Of course It shows some wifi menu, vpn config menu and more capable firewall menus. Apart from these same font, same color, same table everything same. I checked the bottom of device, it shows it is made by UTStarcom and manufactured in China. My home modem has No info though. It should be either Beetel modem is also manufactured by UTStarcom OR Broadcom chip vendor has supplied the same code base to these OEMs.

I ventured telent-ing into the box. I see 'some' difference here though. I see fixed menu showing. In my home modem, you have to press ? to get the list of commands supported. I typed 'sh' to get a unrestricted busybox shell -so that is same. Just like beetel modem this box's software bulid doesn't support 'ls' command so used 'echo *' to list the files. Software sports 2.6.8 kernel and gcc version 3.4.2, uClibc library. The software version of the box has 'bsnl' in it. It suggests me that code base for both BSNL and Beetel modems are same and separately built.

The Hardware is has got some more muscle

Wifi Chipset,
4 LAN ports
14MB RAM
3MB Flash

It makes sense as my office is using business class ADSL .

I have one more ADSL+everything kinda box with me. it is imported!! I am going to work on it and make it work with BSNL Line. Hope it works, Watch this space for updates.

Tearing apart ADSL Router - Beetel 110BX1 ADSL Router

Looks like the bcm96338 based modems are widely used by Indian ISPs not just Airtel.Little bit more google helped me break into the box. Thanks to http://www.cyberciti.biz/tips/hacking-beetel-220x-adsl-router-broadcom-bcm6338.html for the tips.

I found 2 major flaws in the ADSL-router software.

Hack#1: In web browser, key in http://192.168.1.1/main.html Bingo! It opens the web interface No Login/Password asked!! Must be a developer's page, overlooked during release!!

Hack#2: After logging in to telnet, type 'sh' it opens helplessly a Busybox shell coming out of the fixed menu, revealing entire system. so much for 'hardening'!!

Tip: there is no ls.use echo * instead.

In the last post I had mentioned that I am going to find our CPU and Linux Info. Once you got the entire shell these are the least of the info you can find.

Just for the record, The system has IPTables and ebtables, runs linux 2.6.8, gcc version 3.4.2. Looks like the vendor has not been spending $$ on software lately.


Syaonara.

Sneak Peek into my ADSL Router - Beetel 110BX1 ADSL Router

I have been using Airtel's DSL connection for some time now. I always wanted to see what the are all the capabilities of my "Modem" sitting on my desktop. The Modem reads Beetel 110Bx1 ADSL2 + Router. Today finally I got down to the device and took a look at the beast.
It is a simple device is running (hardened) Linux.

Hardware
- 6MB RAM
- 1.4MB Flash (fully utilized)
- Broadcom chipset, revealed during telnet login.
BCM96338 ADSL Router
Login:
- Single core CPU
- one RJ45 for LAN and One RJ11 for ADSL input line.

Software
- Telnetd , Login:admin, pwd:password
- Httpd (microhttpd, which is very light weight) Login:admin, pwd:password
All config are possible thru web interface.
- No SSH
- Shell is hardened - exposes very limited set of commands.
- Linux contains bridge utilities(brctl is available) The device is actually 'Bridge'.
- Runs a NAT
- Runs simpler form of ACL on Firewall
- Being Linux, it has QoS which is marking of packets with DSCP Values for selected source/destination IP/Port combination.
- It Also has DMZ and D-NAT.
- DHCP and DynDNS client.
- My modem says it runs "3.12L.01.A2pB023k.d20k_rc2" version.
- NTP Client
- as i suspected it runs Busybox v1.0
- All these are packed in 21 processes! (plus my telnet process)



Considering the software functionality and corresponding hardware muscle, It means there's no flab in system. The developers have definitely done a good job. This box says, it is imported by Bharti Teletech Ltd. Too bad it doesn't show who is the original manufacturer even worse country of origin too.

Kudos, whoever developed this 'Router' which works just fine, doesn't use too much resources and still provides all needed s/w features.

What I do not know now is the CPU speed, make Linux version. Let me see if i can break in and find out this.

Average Ethernet Packet size

As on Y2000, the packet size distribution looked something like this...

Downstream Upstream
---------- -------------
0 - 64 14.68 58.49
65 - 127 13.87 29.73
128 - 255 7.25 1.72
256 - 511 6.44 3.98
512 - 1023 13.59 3.37
1024 - 1518 44.17 2.70

Reported by:
Steve Dispensa
Sr. Network Architect
Sprint Broadband Wireless Group

Anatomy of initrd image

Lets say, you have a Linux Installer CD/Live CD, and you want to know what your system does immediately after booting kernel. initrd image is the place you might want to look at.
Initrd is actually a zipped , cpio archive of the hierarchy of directory structure. It contains init script aka mother of all processes. copy your initrd image into tmp folder. Then issue the following command.

$gunzip initrd.gz
$cpio -id < inird

This will create the entire directory structure. you will find 'init' as executable. If you are using a Linux-installer CD OR Live DVD chances are the initrd image uses busybox.

Happy Exploring.