PDU - Protocol Data Unit

PDUs are relevant in relation to one of the first 4 layers of the OSI model as follows:

1. The Layer 1 PDU is the bit
2. The Layer 2 PDU is the frame
3. The Layer 3 PDU is the packet
4. The Layer 4 PDU is the segment (e.g. TCP segment)

(Layer 5 and above are referred to as data.)

Reference::

http://en.wikipedia.org/wiki/Protocol_data_unit

Cisco Security Advisor

Reference::
http://www.cisco.com/en/US/products/products_security_advisories_listing.html

Cisco Guide

::SysLog::

How-ToAn Overview of the syslog Protocol 
Get to know your logging options in the Cisco IOS
set logging history through set ntp client

::Stencil::

Download Stencil

::Configuration::

PIX/ASA: Active/Standby Failover Configuration Example

::Command::

10 things you can do with the Cisco IOS service command

::Design::

Video Conference

::Troubleshooting::

High CPU Utilization
Switch Port & Interface Problem
Troubleshooting Router
Understanding EtherChannel Inconsistency Detection
Show Interface Command Output
Troubleshooting Essentials

DHCP

bla bla bla


Reference::
http://articles.techrepublic.com.com/5100-10878_11-5034551.html?tag=rbxccnbtr1

Cisco Switch :: Privilege Mode

Camner nk tukar password Cisco? Actually Cisco ada 2 level akses iaitu user EXEC mode dan privileged EXEC mode.

user EXEC mode (privilege level 1)
- Mode default dlm Cisco
- Bleh akses fungsi asas switch/router seperti status interface, routing table etc2
- Tak boleh ubag konfigurasi switch / router
- Untuk tukar password ::
router(config)# username test password test privilege 3

Priveleged EXEC Mode (privilege level 15)
- Taip "enable" dlm user EXEC mode akan membawa kpd mode ini
- Boleh akses keseluruhan fungsi dlm switch / router.
- Utk tukar pass ::
router(config)# enable secret level 5 level5pass

Untuk tengok priveleged, boleh issue command ::

router# show privilege 
Current privilege level is 3

Reference::

http://articles.techrepublic.com.com/5100-10878_11-5659259.html
http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/12.1/20ew/configuration/guide/supcfg.html#wp1021778
http://www.cisco.com/en/US/docs/ios/12_2/security/configuration/guide/scfpass.html
http://www.cisco.com/en/US/docs/ios/12_2t/12_2t13/feature/guide/ftprienh.html#wp1027195
http://www.petri.co.il/csc_how_to_configure_local_username_database_cisco_ios.htm

Covert Video File Format

Kalo guna ubuntu, bleh pkai ffmeg utk convert file video FLV kpd lain-lain format seperti WMV, AVI dan MP3. Aku convert nie coz nk play video nie dalam streaming server guna Window Media Services.

Convert FLV kpd WMV
----------------------------------------
ffmpeg -i ustaz\ azhar\ idrus\ -\ sunnah\ \&\ kias\ kepal\ tanah\ kubur.flv -vcodec wmv1 -acodec adpcm_ima_wav tanah-kubur.wmv

Convert FLV kpd AVI
----------------------------------
ffmpeg -i 10-ustaz\ azhar\ idrus\ -\ hukum\ jaga\ \&\ beri\ nafkah\ kpd\ orang\ tua.flv -vcodec msmpeg4v2 test.avi

Convert FLV kpd MP3
-------------------------------------

Basic ::

ffmpeg -i inpuvvideofile.flv outputaudiofile.mp3

By default, ffmpeg akan encode mp3 kpd 64kb/s. Guna command -ab untuk tukar kepada 128kb/s.

ffmpeg -i inpuvvideofile.flv -ab 128k outputaudiofile.mp3

By default, mp3 file telah di encode ke dlm file FLV. Guna command -acodec copy untuk output yg lebih cepat.

ffmpeg -i inpuvvideofile.flv -acodec copy outputaudiofile.mp3

Untuk check file FLV lebih details, issue command di bawah ::

ffmpeg -i inputvideo.flv

Youtube ke MP3 (Play dahulu file Youtube sampai habis)

ffmpeg -i /tmp/FlashTAx7jp -acodec libmp3lame output.mp3

Reference ::
https://wiki.ubuntu.com/ffmpeg
http://ubuntuforums.org/archive/index.php/t-343537.html
http://gebaar.blogspot.com/2009/06/howto-easily-enable-mp3-mpeg4-aac-and.html
http://ubuntuforums.org/showthread.php?t=852027
http://ubuntuforums.org/showthread.php?t=786095
http://pasindudps.blogspot.com/2010/12/compiling-ffmpeg-in-ubuntu-1010.html

Networking :: Socket Programming

Nak blajar socket programming?


Reference::
Beej Socket Programming
Devshed.Com