Some funny comics about Steve Jobs

Animated Video Wallpaper for JB iphone

It’s no longer only Android phone enjoys the animated wallpaper & lockscreen on their phone! Now you can have one, if you have a jailbroken iphone.

1. Start your Cydia, and go to “Manage”.
2. Then select “Source” and add the following source :
   • http://i.danstaface.net/deb/

   

3. Upon completion of the source update, search for “vWallpaper2 for iOS4” and install it.

   

4. Then,  your iphone will be respring by itself and vWallpaper is ready to use on your desktop.

Additional video wallpaper source :

• http://cydia.myrepospace.com/PizentuDeWind

The iPhone evolution

Are you an iPhone fan/supporter?

Source : The iPhone Evolution

How travelers use in-flight WIFI

Source : How Travelers Use In-Flight WIFI

Top 30 Cydia Tweeks and Apps!

Nslookup works but ping cannot resolve domain name?!

Have you experience this? Able to resolve using nslookup but failed to resolve the DNS when perform ICMP ping or traceroute ?

Here’s the solution that you may try, disable the DNS Cache :

> net stop dnscache      or

> sc servername stop dnscache

How to completely remove contacts on your iPhone?

1. Go to “Settings” application on your iPhone.

2. Click on “Mail, Contacts, Calendars” option.

3. Add a new account & select “Microsoft Exchange”

4. Then key in your Gmail username & password. Use “m.google.com” as its Server.

5. Toggle the “Contacts” sync and there will be a prompt to delete all contacts from your iphone.

 

6. Done.

Play Angry Birds on your PC!

Now, you no need to have iphone/ipad or android phone to play Angry Bird! All you need is a PC with Google Chrome installed!

Check it out! 

Open / Download the free Google Chrome

Download from Google Chrome Web Store and install.

Browse to http://chrome.angrybirds.com and start playing!

The Complete iPhone 5 Rumor Roundup

Mac Comparisons within 10 years!!!

OSI Model : Layer 2 (DLC)

Further to last post on OSI model, let me continue with some information on it. There’re some key parameters that embedded in every layer in one traffic.

Legend :
DA=Destination Address
SA=Source Address
FCS=Frame Check Sequence based on Cyclic Redundancy Check (CRC)
SP=Source Port
DP=Destination Port

Layer 2 frame header Overview

Offset 0-5 and Offset 6-11

At layer 2 (Data Link Control Layer)  frame header, source & destination MAC address will be the key parameters ( as shown in the ASCII packet below ). It takes up 6 Bytes for each layer-2 DA & SA and start from offset 0000 in your sniffer’s pcap file.

*( Note : Sniffer will start the capture from Layer-2 DA & SA range, and normally Preamble & 32-bit FCS/CRC will be left )

Offset 12-13

The following 2 Bytes are allocated for the Ethertype, in the example above shows it’s IP type ( 0x0800 ). More info in IEEE Ethertype. This 2 Bytes will indicate the following layer-3 IP header type.

Beside the example here which is Ethernet Version 2 Frame, there’re also some other 802.3 type e.g. IEEE 802.3 LLC Frame, IEEE 802.3 SNAP Frame & Novell Netware 802.3 RAW Frame.

Offset 15-17

If the 2 Bytes following the SA is greater than 05DC HEX ( 1500 Decimal ), the station will identified by Ethernet Version 2. Else, they’re assumed to be a length field. When the following 2 Bytes showing 802.3 length as 38 Decimal ( 26 HEX ) means the following Bytes will be LLC ( Logical Link Control ) header. This sub-layer is acts as an interface between MAC sublayer and the network layer.

Both DSAP ( Destination Source Service Access Point ) & SSAP ( Source Service Access Point ) will be taking up 1 Bytes respectively. This is simply to be the pointer to a memory buffer in the receiving station & of the sending process. Some example will DSAP/SSAP=43, means the following header will be BPDU ( Bridge Protocol Data Unit ).

HEX AA (DEC 170) values are usually employed for the DSAP and SSAP values. Netware uses a HEX 03 in the SNAP Control field and will use the 0x81-37 Ethernet Type value. Usually, the Organizational Code is coded as all 0s (0x00-00-00) and NetWare is no exception.

Offset 17 is simply the Control Byte.

Offset 15-17 

The first 3 Bytes i.e. Offset 15-20 is the vendor code. Refers IANA assigned Ethernet-numbers.

Offset 21-22 is the local code, that typically indicate the IEEE Ethertype. This is where the backwards compatibility with Version II Ethernet is implemented.

VLAN (  Optional frame header )

802.1q VLAN tagged frame, is an IEEE standard, uses an additional header in the frames that identifies the VLAN. The 4 Bytes of 802.1q VLAN tag after Layer-2 DA & SA, the Offset 12-15, but it’s optional.

VLAN tag takes up 32 bits in the frame header. The first 16 bits, which located at Offset 12-15 which same with the EtherType/Size field in the untagged frame, is the Tag Protocol Identifier (TPID).

The following 2 Bytes ( 16 bits ) is the Tag Control Identifies (TCI). Priority Code Point( (PCP) the 3-bit field which refers to the IEEE802.1p priority. This indicates the frame priority level, from value DEC 0 (Best Effort) to value DEC 7 (Highest). CFI, or known as Canonical Format Identifier, 1 bit field. CFI normally used to identify between Ethernet ( value 0 ) or Token Ring ( value 1 ).

Another 12-bit field specifying the VLAN to which frame belongs. A value of 0 means that the frame does not belong to any VLAN.

In the case of Q-in-Q ( IEEE802.1ad ), another additional 4 Bytes of VLAN tagging is needed in the frame header. The first 4 Bytes which next to SA will representing the S-TAG ( Service Tag ) and the following 4 Bytes will be representing the C-TAG ( Customer Tag ). IN this case, TPID of the outer S-TAG will be using 0x88A8 to identify it as Q-in-Q packet.

 

To be continued….

Related Post : OSI Model Standard

Comparisons : iPad2 & others

Between iPad & iPad 2 :

Original Post:

iPad 2: Still Ahead of The Competition? 
iPad vs iPad 2
iPad 2 vs HP TouchPas vs Motorola Xoom vs BlackBerry PlayBook

Other related post:  iPad vs. Xoom vs. iPad 2 Spec Comparison Chart

See how fast Android grow!

Firefox getting slower and slower?

Here’re some tips to tune and tweak your Firefox when it getting slower and slower ( or upon installation ) :

Modify the firefox config file

It’s easy to modify, just type “about:config” in your firefox browser, then search for the following parameters and change the value ( just like how you change your registry ) :

• network.http.pipelining,  set the value from false to true.
• network.http.pipelining.maxrequests, change the value from default 4 to a higher value i.e. 8
• network.http.proxy.pipelining, set the value from false to true.
• browser.sessionstore.interval, change the value from 10000 (10 secs) to 120000 (2 minutes) to increase the firefox backup the session restore point interval.
• Add the following parameter ( New->Integer ) and set the value to 0, nglayout.initialpaint.delay.

Securing yourself from a world of hackers

*Above = Copy Pasted from other’s post.

Also check out my earlier post Good Password Practices

ASCII Table

Source From : http://www.asciitable.com/

ASCII stands for American Standard Code for Information Interchange. Computers can only understand numbers, so an ASCII code is the numerical representation of a character such as 'a' or '@' or an action of some sort. ASCII was developed a long time ago and now the non-printing characters are rarely used for their original purpose. Below is the ASCII character table and this includes descriptions of the first 32 non-printing characters. ASCII was actually designed for use with teletypes and so the descriptions are somewhat obscure. If someone says they want your CV however in ASCII format, all this means is they want 'plain' text with no formatting such as tabs, bold or underscoring - the raw format that any computer can understand. This is usually so they can easily import the file into their own applications without issues. Notepad.exe creates ASCII text, or in MS Word you can save a file as 'text only'

Slow SSH connection in Ubuntu

There is always a problem with Ubuntu’s i.e. very slow SSH connection. For some reasons, there’re some options are being enabled by default and causing either the incoming or outgoing SSH connection very slow or hanged in a range from 15 to 60 seconds.

There’re two major contributors which I know of, than can causing the abovementioned problem.

[1] GSSAPIAuthentication

GSSAPI is a ITEF standard for doing strong encrypted authentication in network based applications. OPENssh uses this API and the underlying kerberos 5 code to provide a alternative means of authentication other than ssh_keys.

For some reasons, this feature is enabled by default since Ubuntu Fiesty, you can disable them globally affecting all users in the /etc/ssh/ssh_config

# SendEnv LANG LC_*
# HashKnownHosts yes
# GSSAPIAuthentication yes
# GSSAPIDelegateCredentials no

[2] Slow or Broken DNS Lookup

Everytime when you log into the OpenSSH server, it would actually perform a reverse-lookup on your IP address. If the DNS lookup timed out, then you’ll having big time of delaying as typically OpenSSH will perform 3 times trying.

All you need to do is add the following line in /etc/ssh/ssh_config

sudo echo "UseDNS no" >> /etc/ssh/sshd_config

Remember to restart the ssh services upon change.