Hard drive noise, power, rpm (Seagate & Western Digital)

1.4

Drive	Noise Idle	Noise RW	Power Idle	Power RW	GB	RP M	Size
ST1000DL002	21	23	4.5	5.8	1000	5900	3.5
ST1000DM003	24	25	4.0	5.9	1000	7200	3.5
ST1500DL003	21	23	4.5	5.8	1500	5900	3.5
ST2000DL003	21	23	4.5	5.8	2000	5900	3.5
ST2000DM001			5.8	8.0
ST2000VX000
ST2000VX002	27	28	0.5	5.8	2000	5900	3.5
ST250DM000	22	23			250	7200	3.5
ST31000322CS		24	3.8	4.1	1000	5900	3.5
ST31000333AS	27	29			1000	7200	3.5
ST31000340AS	27	29			1000	7200	3.5
ST31000340NS	29	32	8	10.6	1000	7200	3.5
ST31000520AS					1000	5900
ST31000524AS	25	27	5	9.4	1000	7200	3.5
ST31000524NS	22	28	4.61	7.42	1000	7200	3.5
ST31000525SV	27	28	7	10.4	1000	7200	3.5
ST31000526SV	27	28	1	7	1000	7200	3.5
ST31000528AS	26	28			1000	7200	3.5
ST31000640SS		27	9	12.5	1000	7200	3.5
ST3120210AS	27	29			120	7200	3.5
ST3120211AS	27	29			120	7200	3.5
ST3120213A	25	28			120	7200	3.5
ST3120810AS	27	29			120	7200	3.5
ST3120811AS	27	29			120	7200	3.5
ST3120814A	25	28			120	7200	3.5
ST3146356SS	35	37			146	15000	3.5
ST3146807LC		36			146.8	10000	3.5
ST3146855LC	35	37			146.8	15000	3.5
ST3146855LW	36				146.8	15000	3.5
ST31500341AS	28	29			1500	7200	3.5
ST31500541AS					1500	5900
ST3160210AS	27	29			160	7200	3.5
ST3160211AS	27	29			160	7200	3.5
ST3160212A	25	28			160	7200	3.5
ST3160215A	28	29			160	7200	3.5
ST3160215AS	28	29			160	7200	3.5
ST3160318AS	26	28	4.6	6.2	160	7200	3.5
ST3160810AS	27	29			160	7200	3.5
ST3160811AS	27	29			160	7200	3.5
ST3160812A	25	28			160	7200	3.5
ST3160813AS	23	26			160	7200	3.5
ST3160815A	28	29			160	7200	3.5
ST3160815AS	28	29			160	7200	3.5
ST32000542AS	25	26			2000	5900	3.5
ST32000641AS	27	29	6.39	9.23	2000	7200	3.5
ST32000644NS	27	30	6.39	9.03	2000	7200	3.5
ST3200820A					200	7200	3.5
ST3200822A					200	7200	3.5
ST3200827ACE	25	26			200	7200	3.5
ST320DM000	22	23			320	7200	3.5
ST320LT020	20	22	0.48	1.4	320	5400	2.5
ST320LT022	20	22	0.48	1.4	320	5400	2.5
ST3250310AS	27	28			250	7200	3.5
ST3250310NS	25		8	10.6	250	7200	3.5
ST3250312AS	26	28	5	8	250	7200	3.5
ST3250318AS					250	7200
ST3250410AS	27	28			250	7200	3.5
ST3250620AS	25	30			250	7200	3.5
ST3250624AS	27	29			250	7200	3.5
ST3250820A	25	30			250	7200	3.5
ST3250820AS	25	30			250	7200	3.5
ST3250824AS	25	28			250	7200	3.5
ST33000651AS	28	32	6.39	9.23	3000	7200	3.5
ST3300655LC					300	15000	3.5
ST3300655LW		36			300	15000	3.5
ST3300656SS	35	37			300	15000	3.5
ST3300657SS	36		8.74	12.92	300	15000	3.5
ST3300822AS	27	29			300	7200	3.5
ST3320413AS	26	28	5	8	320	7200	3.5
ST3320418AS	26	28	4.6	6.2	320	7200	3.5
ST3320613AS	25	26			320	7200	3.5
ST3320620A	25	30			320	7200	3.5
ST3320620AS	25	30			320	7200	3.5
ST3320633AS	27	29			320	7200	3.5
ST3320820AS	25	30			320	7200	3.5
ST3320833A	28	32			320	7200	3.5
ST3320833AS	27	29			320	7200	3.5
ST3400620A	28	37			400	7200	3.5
ST3400620AS	28	37			400	7200	3.5
ST3400633A	28	32			400	7200	3.5
ST3400832A	28	37			400	7200	3.5
ST3400833AS	27	29			400	7200	3.5
ST3402111A	20	24			40	7200	3.5
ST340211AS	27	29			40	7200	3.5
ST3450857SS	36		10.1	14.6	450	15000	3.5
ST3500312CS			3	3.4	500	5900	3.5
ST3500320AS	25	28			500	7200	3.5
ST3500320NS	27	32	8	10.6	500	7200	3.5
ST3500410AS					500	7200	3.5
ST3500412AS	19	20	3	4	500	5900	3.5
ST3500413AS	26	28	6	8	500	7200	3.5
ST3500418AS					500	7200	3.5
ST3500514NS	19	27	3.74	6.47	500	7200	3.5
ST3500620AS	25	28			500	7200	3.5
ST3500630A	28	37			500	7200	3.5
ST3500630AS	28	37			500	7200	3.5
ST3500630S	28	37			500	7200	3.5
ST3500641A	28	32			500	7200	3.5
ST3500832A	28	32			500	7200	3.5
ST3600057SS	36		11.68	16.35	600	15000	3.5
ST3640323AS	25	28			640	7200	3.5
ST373455LC					73.4	15000	3.5
ST373455LW	36		8.1		73.4	15000	3.5
ST3750330AS	27	29			750	7200	3.5
ST3750330NS	29	32	8	10.6	750	7200	3.5
ST3750525AS	25	27	6	8	750	7200	3.5
ST3750528AS					750	7200
ST3750630AS	27	29			750	7200	3.5
ST3750630SS	29	32	8	10.6	750	7200	3.5
ST3750640A	28	37			750	7200	3.5
ST3750640AS	28	37			750	7200	3.5
ST3750640NS	27		9.3	13	750	7200	3.5
ST3750640SV	28	37			750	7200	3.5
ST380210A	25	27			80	7200	3.5
ST380211AS	27	29			80	7200	3.5
ST380215A	28	29			80	7200	3.5
ST380215AS	28	29			80	7200	3.5
ST380810A	25	27			80	7200	3.5
ST380811AS	27	29			80	7200	3.5
ST380815AS	28	29			80	7200	3.5
ST500DM002				6.19	500	7200	3.5
ST500NM0001	27		4.67	7.89	500	7200	3.5
ST910021AS	25	29			100	7200	2.5
ST9100821AS	25	29			100	7200	2.5
ST9100824A	24	29			100	5400	2.5
ST9100824AS	24	29			100	5400	2.5
ST9100828A	24	30			100	5400	2.5
ST9100828AS	24	30			100	5400	2.5
ST9120817AS	24	26			120	5400	2.5
ST9120821A	24	29			120	5400	2.5
ST9120821AS	24	29			120	5400	2.5
ST9120822A	24	30			120	5400	2.5
ST9120822AS	24	30			120	5400	2.5
ST9120823AS	25	29			120	7200	2.5
ST9160310AS					160	5400	2.5
ST9160314AS	24	26			160	5400	2.5
ST9160411AS	23	25			160	7200	2.5
ST9160821A	24	30			160	5400	2.5
ST9160821AS	24	30			160	5400	2.5
ST9160823AS	25	29			160	7200	2.5
ST9160827AS	24	26			160	5400	2.5
ST9200420AS	25	29			200	7200	2.5
ST9200827AS	24	26			200	5400	2.5
ST9250315AS	24	26			250	5400	2.5
ST9250410AS	23	25	0.67		250	7200	2.5
ST9250421AS	23	25			250	7200	2.5
ST92505610AS	23	26	0.8	2.2		7200	2.5
ST9250827AS	24	26			250	5400	2.5
ST9320320AS					320	5400	2.5
ST9320325AS					320	5400	2.5
ST9320421AS	23	25			320	7200	2.5
ST9320423AS					320	7200	2.5
ST93205620AS	23	26	0.8	2.2		7200	2.5
ST93811A	24	29			30	5400	2.5
ST93811AS	24	29			30	5400	2.5
ST94015A	25	29			40	7200	2.5
ST940814AS	24	30			40	5400	2.5
ST940815A	24	30			40	5400	2.5
ST94813A	24	29			40	5400	2.5
ST94813AS	24	29			40	5400	2.5
ST9500325AS	24	26	1.4	1.54	500	5400	2.5
ST9500325ASG	24	26	1.4	1.78	500	5400	2.5
ST9500420AS	23	25	0.67		500	7200	2.5
ST95005620AS	23	26	0.8	2.2		7200	2.5
ST96023A	25	29			60	7200	2.5
ST96023AS	25	29			60	7200	2.5
ST960813AS	24	30			60	5400	2.5
ST960815A	24	30			60	5400	2.5
ST9640320AS	23	26	0.68	1.25	640	5400	2.5
ST96812A	24	29			60	5400	2.5
ST96812AS	24	29			60	5400	2.5
ST9750423AS	23	26	0.5	1.4	750	5400	2.5
ST980411AS	23	25			80	7200	2.5
ST980811AS	24	30			80	5400	2.5
ST980813AS	25	29			80	7200	2.5
ST980813ASG	25	29			80	7200	2.5
ST980815A	24	30			80	5400	2.5
ST980825A	25	29			80	7200	2.5
ST980825AS	25	29			80	7200	2.5
ST98823A	24	29			80	5400	2.5
ST98823AS	24	29			80	5400	2.5
STM31000340AS	25	30			1000	7200	3.5
STM31000528AS	25	27	5	10.4	1000	7200	3.5
STM3160215A	27	29			160	7200	3.5
STM3160215AS	27	29			160	7200	3.5
STM3160815AS	27	29			160	7200	3.5
STM3250310AS	25	30			250	7200	3.5
STM3250318AS	26	28	5	8	250	7200	3.5
STM3250820A	25	30			250	7200	3.5
STM3250820AS	25	30			250	7200	3.5
STM3320613AS	25	30			320	7200	3.5
STM3320820A	25	32			200	7200	3.5
STM3320820AS	25	30			320	7200	3.5
STM3500320AS	25	30			500	7200	3.5
STM3500418AS	26	28			500	7200
STM3750330AS	25	30			750	7200	3.5
STM380215A	27	29			80	7200	3.5
STM380215AS	27	29			80	7200	3.5
STM380815AS	27	29			80	7200	3.5
STM940215A	24	29			40	5400	2.5
STM960212A	24	29			60	5400	2.5
STM980215A	24	29			80	5400	2.5
WD1000FYPS	24	29			1000		3.5
WD1001FALS	24	33			1000	7200	3.5
WD1002FAEX	28	33	6.1	6.8	1000	7200	3.5
WD1002FBYS	28	33			1000	7200	3.5
WD1003FBYX	28	33	5.9		1000	7200	3.5
WD10EACS	25	27			1000	5400	3.5
WD10EADS	25	27			1000		3.5
WD10EADX	23	27	2.8	4.9	1000		3.5
WD10EALS	28	33	6.1	6.8	1000	7200	3.5
WD10EALX	28	33	6.1	6.8	1000	7200	3.5
WD10EARS	23	27	2.8	4.86	1000		3.5
WD10EARX	23	27	2.8	4.86	1000		3.5
WD10EFRX	21	22	3.2	3.7	1000		3.5
WD10EUCX	23	24	3.3	5.3	1000		3.5
WD10EURS	23	24	4.2	4.9	1000		3.5
WD10EURX	23	24	3.3	5.3	1000		3.5
WD10EVDS	24	25	4.2	4.9	1000	5400	3.5
WD10EVVS	24	25	4.2	4.9	1000	5400	3.5
WD10EZEX	29	30	6.1	6.8	1000	7200	3.5
WD10EZRX	21	22	3.3	5.3	1000		3.5
WD10TPVT	24	25	0.75	1.7	1000	5200	2.5
WD1200BEAE	20	21			120	5400	2.5
WD1200BEVE	20	21			120	5400	2.5
WD1200BEVS	24	26			120	5400	2.5
WD1200BEVT	24	26	0.1	2.5	120	5400	2.5
WD1200JB	28	29			120	7200	3.5
WD1500HLFS	27	34	4.5	6	150	10000	3.5
WD1501FASS	29	34	8.2	10.7	1500	7200	3.5
WD1502FAEX	29	34	8.2	10.7	1500	7200	3.5
WD1502FYPS	25	29	0.8	6.8	1500		3.5
WD1503FYYS	29	34	8.2	10.7	1500	7200	3.5
WD15EADS	25	29			1500	5400	3.5
WD15EARS	24	29	2.75	4.73	1500		3.5
WD15EARX	24	29	2.5	4.5	1500		3.5
WD15EURS	24	25	4.8	5.3	1500		3.5
WD15EVDS	25	26	4.9	5.9	1500	5400	3.5
WD15EZRX	24	29	5.5	6	1500		3.5
WD1600AABB	30	32			160	7200	3.5
WD1600AABBS	30	32			160	7200	3.5
WD1600AAJB	24	27			160	7200	3.5
WD1600AAJS	26	31			160		3.5
WD1600BEKT	22	25	0.85	2.5	160	7200	2.5
WD1600BEVE	23	25			160	5400	2.5
WD1600BEVS	24	26			160	5400	2.5
WD1600BEVT	24	26			160	5400	2.5
WD1600BPVT	24	25	0.85	1.6	160	5400	2.5
WD1600JB	28	29			160	7200	3.5
WD1600JS	28	29			160	7200	3.5
WD2000BB	30	32			200	7200	3.5
WD2000JB	28	29			200	7200	3.5
WD2000JS	28	29			200	7200	3.5
WD2001FASS	29	34	8.2	10.7	2000	7200	3.5
WD2002FAEX	29	34	6.1	10.7	2000	7200	3.5
WD2002FYPS	25	29	0.8	6.8	2000		3.5
WD2003FYYS	29	34	8.2	10.7	2000	7200	3.5
WD20EADS	24	29	3.7	6	2000	5200	3.5
WD20EARX	24	29	2.5	4.5	2000		3.5
WD20EFRX	23	24	4.1	4.4	2000
WD20EURS	24	25	4.8	5.3	2000		3.5
WD20EVDS	25	26	4.9	5.9	2000	5400	3.5
WD20EZRX	3.5	29	5.5	6	2000		3.5
WD2500AAJB	25	29			250	7200	3.5
WD2500AAJS	25	26	7.2	7.8	250	7200	3.5
WD2500AAKS	28	33			250	7200	3.5
WD2500AAKX	29	30	5.6	6	250	7200	3.5
WD2500BB	30	32			250	7200	3.5
WD2500BEKT	22	25			250	7200	2.5
WD2500BEVE	23	25			250	5400	2.5
WD2500BEVS	24	26			250	5400	2.5
WD2500BEVT	24	26			250	5400	2.5
WD2500BJKT	22	25	0.15	2.5	250		2.5
WD2500BPVT	22	25	0.85	2.5	250	5400	2.5
WD2500JB	28	29			250	7200	3.5
WD2502ABYS	25	29			250	7200	3.5
WD25EZRSDTL	24	29	5.5	6	2500		3.5
WD25EZRX	24	29	5.5	6	2500		3.5
WD3000BKFG	27	34	5.2	7.4	300	10000	2.5
WD3000GLFS	29	36			300	10000	2.5
WD3000HLFS	27	34	4.5	6	300	10000
WD30EFRX	23	24	4.1	4.4	3000		3.5
WD30EURS	23	24	4.1	4.4	3000		3.5
WD30EZRSDTL	24	25	5.5	6.3	3000		3.5
WD30EZRX	23	27	5.5	6	3000		3.5
WD3200AAJB	28	33			320	7200	3.5
WD3200AAKS	29	30	4.92	5.36	320	7200	3.5
WD3200AAKX	29	30	5.6	6	320	7200	3.5
WD3200BEKT	22	25			320	7200	2.5
WD3200BEVE	22	25			320	5400	2.5
WD3200BEVT	24	26			320	5400	2.5
WD3200BJKT	22	25	0.15	2.5	320		2.5
WD3200BPVT	24	26	0.85	2.5	320	5400	2.5
WD3200JB	28	33			320	7200	3.5
WD3202ABYS	25	29			320	7200	3.5
WD4000AAJB	28	29			400	7200	3.5
WD4000AAJS	28	29			400	7200	3.5
WD4000AAKB	28	33			400	7200	3.5
WD4000AAKS	28	33			400	7200	3.5
WD4000BEVT	24	26			400	5400	2.5
WD400BB	30	32			40	7200	3.5
WD400BD	30	32			40	7200	3.5
WD400BEAE	20	21			40	5400	2.5
WD400BEAS	24	26			40	5400	2.5
WD400BEVE	20	21			40	5400	2.5
WD400BEVS	24	26			40	5400	2.5
WD400JB	28	29			40	7200	3.5
WD400JD	28	29			40	7200	3.5
WD4500BKHG	28	34	5.4	8.3	450	10000	2.5
WD4500HLHX	27	34	4.3	6.4	450	10000
WD5000AACS	25	27			500	7200	3.5
WD5000AADS	25	29			500	5400	3.5
WD5000AAJB	28	29			500	7200	3.5
WD5000AAJS	28	29			500	7200	3.5
WD5000AAKB	25	29	7.7	8.3	500	7200	3.5
WD5000AAKS	28	33	5.6	6	500	7200	3.5
WD5000AAKX	28	33	5.6	6	500	7200	3.5
WD5000AAVS	24	29			500		3.5
WD5000AUDX	21	22	2.6	3.7	500		3.5
WD5000AVCS	21	22	3	4	500		3.5
WD5000AVDS	21	22	3.7	4.1	500		3.5
WD5000AZRX	21	22	2.6	3.8	500		3.5
WD5000BEKT	25	28	0.83	1.8	500	7200	2.5
WD5000BEVT	24	26			500	5400	2.5
WD5000BPKT	28	28	0.8	1.75	500	7200	2.5
WD5000BPVT			0.25	2.5	500	5400	2.5
WD5001AALS	25	29			500	7200	3.5
WD5002AALX	29	34	8.2	10.7	500	7200	3.5
WD5002ABYS	25	29	6.6	7.1	500	7200	3.5
WD5003ABYX	27	30	4.5	6.4	500	7200	3.5
WD6000BKHG	28	34	5.4	8.3	600	10000	2.5
WD6000HLHX	27	34	4.3	6.4	600	10000
WD600BEAS	24	26			60	5400	2.5
WD600BEVE	20	21			60	5400	2.5
WD600BEVS	24	26			60	5400	2.5
WD6400AACS	24	29			640		3.5
WD6400AADS	25	27			640		3.5
WD6400AAKS	25	29	7.7	8.3	640	7200	3.5
WD6400AARS	23	27	2.8	4.86	640		3.5
WD6400BEVT	22	25	0.65	1.6	640	5400	2.5
WD6400BPVT	22	25	0.65	1.6	640	5400	2.5
WD6401AALS	25	27			640	7200	3.5
WD6402AAEX	28	33	6.1	6.8	640	7200	3.5
WD7500AACS	25	27			750	7200	3.5
WD7500AADS	24	29	2.8	4.9	1000		3.5
WD7500AAKS	28	33			750	7200	3.5
WD7500AALX	28	33	6.1	6.8	750	7200	3.5
WD7500AARS	23	27	2.8	4.9	750		3.5
WD7500AARX	23	27	3.3	5.3	750		3.5
WD7500AVDS	24	25	4.2	4.9	750	5400	3.5
WD7500AVVS	24	25	4.2	4.9	750	5400	3.5
WD7500BPKT	28	28	0.8	1.75	750	7200	2.5
WD7500BPVT	22	25			750	5400	2.5
WD7500KPVT					750	5200	2.5
WD7501AALS	24	29			750	7200	3.5
WD7502AAEX	28	33	6.1	6.8	750	7200	3.5
WD7502ABYS	28	33	1	8.4	750	7200	3.5
WD8000AARS	23	27	2.8	4.86	800		3.5
WD800AAJB	29	30	4.92	5.36	80	7200	3.5
WD800AAJS					80	7200	3.5
WD800BB	30	32			80	7200	3.5
WD800BD	30	32			80	7200	3.5
WD800BEAE	20	21			80	5400	2.5
WD800BEAS	24	26			80	5400	2.5
WD800BEVE	20	21			80	5400	2.5
WD800BEVS	24	26			80	5400	2.5
WD800JB	28	29			80	7200	3.5
WD800JD	28	29			80	7200	3.5
WD10JFCX	24	25	.6	1.4	1000		2.5
WD7500BFCX	24	25	.6	1.4	750		2.5
WD3200BEKX	25	28	.8		320	7200	2.5
WD5000MPCK	15	17	.55	1.5	500	5400	2.5
WD5000BPVT	22	25	.65	1.6	500	5400	2.5
WD3200BPVT	22	25	.85	2.5	320	5400	2.5
WD2500BPVT	22	25	.85	2.5	250	5400	2.5
WD3200LPVX	17	22	.55	1.4	320	5400	2.5
WD2500LPVX	17	22	.55	1.4	250	5400	2.5
WD10SPCX	20	21	.57	1.7	1000	5400	2.5
WD10JPVX	24	25	.59	1.4	1000	5400	2.5
WD7500LPCX	20	21	.57	1.7	750	5400	2.5
WD7500BPVX	24	25	.65	1.6	750	5400	2.5
WD7500BPVT	24	25	.65	1.6	750	5400	2.5
WD5000BPVX	24	25	.59	1.4	500	5400	2.5
WD5000LPVX	17	22	.55	1.4	500	5400	2.5
WD5000LPVT	17	22	.55	1.4	500	5400	2.5
WD40EFRX	25	28	3.3	4.5	4000		3.5
WD30EFRX	23	27	3.0	4.1	3000		3.5
WD20EFRX	23	27	3.0	4.1	2000		3.5
WD10EFRX	21	24	2.5	3.3	1000		3.5
WD4000F9YZ	31	34	8.1	9.5	4000	7200	3.5
WD3000F9YZ	31	34	8.1	9.5	3000	7200	3.5
WD2000F9YZ	31	34	5.9	7.3	2000	7200	3.5
WD1000F9YZ	30	34	4.6	7.1	1000	7200	3.5
WD4003FZEX	29	34	8.1	9.5	4000	7200	3.5
WD4001FAEX	29	34	8.1	9.5	4000	7200	3.5
WD3003FZEX	29	34	8.1	9.5	3000	7200	3.5
WD3003FAEX	29	34	8.1	9.5	3000	7200	3.5
WD2003FZEX	29	34	8.1	9.5	2000	7200	3.5
WD1003FZEX	29	30	6.1	6.8	1000	7200	3.5
WD1002FAEX	28	30	6.1	6.8	1000	7200	3.5
WD5003AZEX	29	30	6.1	6.8	500	7200	3.5
HDS724040ALE640	29		6.1		4000	7200	3.5
HDS5C4040ALE630	25		4.9		4000	5400	3.5
ST4000DM000	25	30	5.0	7.5	4000		3.5
ST3000DM001			5.8	8.0	3000		3.5
ST3000DM003	25	30	5.0	7.5	3000		3.5
HTS545050A7E381			.5	1.8	500	5400	2.5
HTE545050A7E380			.5	1.8	500	5400	2.5
ST1000DX001	22	24	3.4	5.9	1000	7200	3.5
ST2000DX001	24	27	4.5	6.7	2000	7200	3.5
ST4000DX001	23	30	6.2	7.5	4000	5900	3.5
ST2000NM0034			4.84	8.93	2000	7200	3.5
ST4000NM0034			5.73	9.59	4000	7200	3.5
ST5000NM0034			6.96	10.72	5000	7200	3.5
ST6000NM0034			7.97	11.86	6000	7200	3.5
ST2000NM0024			4.5	8.08	2000	7200	3.5
ST4000NM0024			6	9.42	4000	7200	3.5
ST5000NM0024			6.9	11.27	5000	7200	3.5
ST6000NM0024			6.9	11.27	6000	7200	3.5
ST2000VN000	19	21	3	4.3	2000		3.5
ST3000VN000	23	25	3.95	4.8	3000		3.5
ST4000VN000	23	25	3.95	4.8	4000		3.5
ST1000VX000	22	24	3.4	5.9	1000	7200	3.5
ST2000VX000	24	27	5.4	8	2000	7200	3.5
ST3000VX000	24	27	5.4	8	3000	7200	3.5
ST3000VX002	24	26	5	7.5	3000	5900	3.5
ST4000VX000	24	26	5	7.5	4000	5900	3.5
WD10JFCX	24	25	1.4	0.6	1000		2.5
WD2001FFSX	31	34	6.5	8.6	2000	7200	3.5
WD3001FFSX	31	34	6.5	8.6	3000	7200	3.5
WD4001FFSX	31	34	4.9	6.5	4000	7200	3.5
WD50EFRX	25	28	5.3	3.4	5000		3.5
WD60EFRX	25	28	5.3	3.4	6000		3.5
WD7500BFCX	24	25	1.4	0.6	750		2.5
WD5000AZRX	21	22	2.5	3.3	500		3.5
WD40EZRX	25	28	3.4	5.3	4000		3.5
WD50EZRX	25	28	3.4	5.3	5000		3.5
WD60EZRX	25	28	3.4	5.3	6000		3.5
WD20NPVX	24	25	0.8	1.7	2000		2.5
WD15NPVX	24	25	0.8	1.7	1500		2.5
WD2503ABYZ	27	30	4.4	6.5	251	7200	2.5
WD5003ABYZ	27	30	4.4	6.5	500	7200	2.5
WD2000FYYZ	31	34	6.4	9	2000	7200	2.5
WD200MFYYZ	31	34	8.6	10.9	2000	7200	2.5
WD3000FYYZ	31	34	8.6	10.9	3000	7200	2.5
WD4000FYYZ	31	34	8.6	10.9	4000	7200	2.5

Fixing IRC....

From time to time I see stories around the Internet about IRC and various comments about how it should just "be fixed", as if that were something easy to do. Unfortunately "fixing" IRC is quite hard. Why you ask?

IRC (Internet Relay Chat) works by sending messages between clients connected to the edge of a network of connected servers. The network of connected servers might be as few as one or as many as a hundred. Each server passes messages on to other servers or clients depending on various fields in the IRC message. The goal is near to instantaneous transmission of text messages from one client to another. That the transmission isn't instantaneous is where the problems begin.

To think about an IRC network in a more abstract sense, it could be considered to be a large distributed database where each IRC server holds its own copy of the database where the database contains information relating to other IRC servers that are connected to the network, all of the IRC clients that are connected to the network and which server they are connected to and lastly all of the channels (chat rooms) that a client is a member of. All of this information can be used to build a graph that maps the path between any two clients at a given point in time.

When a new client connects to the IRC network, its presence is announced by a message being distributed throughout the IRC network by the server that it first connects to. Similarly messages that represent the client joining a channel are broadcast throughout the network, as too is a message sent out when the client disconnects, effectively removing the client from the database.

When a new server connects to the IRC network its name is announced to all of the other servers in the IRC network, similar to what happens with an IRC client. However it must also receive a complete dump of the IRC database from the server it connected to. When two servers join together with each owning their own IRC network, the fun begins.

If an IRC network becomes divided due to a connection between IRC servers severing then in order to allow the two parts to continue functioning as a chat network, clients are allowed to leave/join, etc. This now means that it is possible for two clients to connect to each half and both choose (for example) the same chat name. When the networks joins back together, each IRC server will see a name collision. This problem is partially overcome with the use of time stamps - synchronised time stamps - but this starts to highlight the problem.

The problem for IRC is that it is a distributed database with clients attached to each database server that want to exchange messages with each other via the servers and not just interact with the server to which it is directly attached. It is a distributed database without any concept of there being a master server making the network of IRC servers functionally similar to a hive: the knowledge about the environment is shared with each and every member knowing everything there is to know.

Whilst there has been consideration given to using multicast, support for it is required across backbone routers but that brings another problem to the fore: reliability. It is essential for a message announcing that a client is joining a chat room reach all of the participants before any messages sent to the chat room for as part of the group communication. Similarly a message announcing a client withdrawing from the network must be distributed after all of the other messages from a client. This rules out using simple protocols that are layered on UDP. To meet all of these usability concerns, TCP is the transport layer protocol that delivers all of the IRC data.

So there you have it: fixing IRC requires developing a new database transport protocol that is light weight, reliable, provides sequenced delivery of data from one side of the Internet to another, allows for databases to merge with potentially conflicting data.