Force10 Networks 100-00055-01 manual Appendix E, Glossary

Appendix E Glossary

ACK	An Acknowledgment packet (ACK) is a packet that is sent from the client to the server to
	complete a TCP connection. See SYN.
DHCP	Dynamic Host Configuration Protocol (DHCP) is a protocol that automatically requests an IP
	address, subnet mask, and default gateway for a network client.
DMA	Direct Memory Access (DMA) is a method by which devices in a hardware system can transfer
	data without occupying the CPU. In the case of the P-Series, the network interface card can
	transfer matched packets directly to the host memory by taking control of the PCI-X bus.
DPI	Dynamic Parallel Inspection (DPI) is an engine based on Multiple Instruction Single Data
	(MISD) hardware architecture that can simultaneously execute thousands of security policies
	and capture/blocking operations on the same data.
Dynamic Rules	Dynamic rules allocate generic registers inside the firmware to allow you to create and modify
	rules at runtime without changing the firmware.
Flow	A flow is a series of packets with the same state. See State.
FPGA	Field Programmable Gate Array (FPGA) is a logic device that is re-programmable; it is a
	counterpart to the Application-Specific Integrated Circuit (ASIC) that cannot be modified once it
	has been programmed.
Garbage	Garbage is data that is no longer necessary; garbage collection is the process of discarding
Collection	this data to free resources. In the context of the P-Series, garbage is old state or flows.
IDS/IPS	Intrusion Detection System/Intrusion Prevention System
MISD	Multiple Instruction Single Data (MISD) is a computer architecture that executes many
	operations simultaneously on one set of data. It is a counterpart to Single Instruction Multiple
	Data (SIMD) and Multiple Instruction Multiple Data (MIMD) architectures.
Null Firmware	Null firmware is firmware that has no static rules. Null firmware is used to maximize the
	dynamic rule capacity on the FPGA.
Offset	Offset is a Snort keyword that specifies a pattern-matching start location within a packet. For
	example, an offset of 5 directs Snort inspect packets beginning after the first 5 bytes of the
	payload. The P-Series does not support this Snort keyword. Rather, the P-Series has an offset
	feature that enables offsets for all rules. This feature is optionally activated during the
	PNIC-Compiler configuration phase.
meta.rules	meta.rules is a Snort rules file supplied with the P-Series appliance by Force10. The rules in
	this file report on flow information and handle possible TCP segmentation evasion attempts.
	They also provide compatibility with Snort, and including them allows you to run Snort on the
	DPI interface.
SFP	Small Form-factor Pluggable (SFP) is an optical transceiver that interfaces a network device
	and a fiber or unshielded twisted pair (UTP) network cable. SFPs support the SONET and
	Gigabit Ethernet standards and can transmit data at a rate of 4.25 Gb/s.

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