NAT

Three Switch Function at Layer 2

Address learning: L2 switches & bridges remembers the source hardware address of each frame received on an interface & they enter this information into MAC address table.

Forward/filter decision: When frame is received on an interface, the switch looks at destination hardware address & find exit interface in the MAC table. The frame is only forwarded out the specified destination port.

Loop avoidance: If multiple connections between switches are created for redundancy, network loop can occur, then STP is used.

SFP

The small form-factor pluggable (SFP) or Mini-GBIC is a compact, hot-pluggable transceiver used for both telecommunication and data communications applications. It interfaces a network device mother board (for a switch, router, media converter or similar device) to a fiber optic or copper networking cable. It is a popular industry format jointly developed and supported by many network component vendors.^[1] SFP transceivers are designed to support SONET, Gigabit Ethernet, Fibre Channel, and other communications standards.

Quote

“Competition in [worldly] increase diverts you, until you visit the graveyards,” (Qur’an 102:1-2).

CISCO IOS VERSIONS

AES Encryption

http://www.cs.bc.edu/~straubin/cs381-05/blockciphers/rijndael_ingles2004.swf

DNS

DHCP

What is firmware and what part does it play in the boot process?

Firmware can be thought of as a combination of hardware and software. ROM (Read Only Memory) is an
example of firmware where we have software, or code, embedded on a memory chip. The memory is nonvolatile,
meaning the information does not go away once the computer is turned off.
Firmware, specifically ROM BIOS, plays a crucial role in the boot process since it contains much of the low level
operating instructions that enable the PC to boot properly. Occasionally when new peripherals are introduced
systems’ BIOS will need to be upgraded in order to recognize the new component.