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HP StorageWorks 2/24 FW 07.00.00/HAFM SW 08.06.00 McDATA Products in a SAN Env - Page 171

Deflate, FastWrite technology, XFR_RDY, number of round trips required to complete a SCSI write

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Implementing SAN Internetworking Solutions 4 and results in a lower compression bandwidth. The algorithm has an average compression ratio increase of approximately 30% over LZO. The algorithm is recommended when up to 8 TCP sessions are used and the available bandwidth is between 10 Mbps (thin Ethernet) and 45 Mbps (DS3 transport level). - Deflate - This algorithm incorporates a history cache with Huffman encoding. In addition, a hash table (saved in the compressed data) is used to perform string searches. Deflate is a processor-intensive algorithm with the highest compression ratio. The algorithm is restricted to use for 10 Mbps (thin Ethernet) links. Note that a data compression ratio cannot be definitively stated, because it changes instantaneously with every data byte transmitted. A consistent byte pattern can be compressed more than a random byte pattern. For example, a defined, constant pattern can often be compressed 15:1. Already-compressed data (such as many graphic formats and some tape formats) cannot be compressed further (1:1). Most data streams are compressible from between 2:1 and 15:1, depending on the density of consistent patterns. The only way to accurately determine a compression ratio is to compress the data and measure the result. • FastWrite technology - SCSI is a simplex protocol that sends a portion of a write command, then waits for a response. Multiple commands can coexist, resulting in an inefficient process on high-latency links. FastWrite is an algorithm that reduces the number of round trips required to complete a SCSI write command to one round trip. The software improves performance over WANs by mitigating the effects of latency and using the entire link bandwidth (because all data is transmitted simultaneously). The FastWrite algorithm responds to initiator write commands with local transfer ready (XFR_RDY) commands that cause the initiator to transmit an entire data set, then buffers the output data at the SAN router closest to the corresponding target device. This eliminates multiple XFR_RDY command transmissions and minimizes bursty data transfer over the WAN, thus reducing round-trip delays that are characteristic of extended-distance links. Implementing SAN Internetworking Solutions 4-27

Section	Page
Contents	3
Preface	13
Introduction to McDATA Multi-Protocol Products	27
Product Overview	28
Multi-Protocol Hardware	28
SAN Management Applications	31
Directors	32
Director Performance	33
Intrepid 6064 Director	34
Intrepid 6140 Director	36
Intrepid 10000 Director	38
Fabric Switches	41
Fabric Switch Performance	41
Sphereon 3232 Fabric Switch	42
Sphereon 4300 Fabric Switch	43
Sphereon 4500 Fabric Switch	44
SAN Routers	46
SAN Router Performance	47
Eclipse 1620 SAN Router	48
Eclipse 2640 SAN Router	50
Product Features	51
Connectivity Features	52
Security Features	54
Serviceability Features	55
Product Management	61
Product Management	62
Out-of-Band Management	62
Inband Management	65
Management Interface Summary	66
Management Server Support	67
Management Server Specifications	68
Ethernet Hub	70
Remote User Workstations	70
Product Firmware	71
Firmware Services	72
Backup and Restore Features	73
SAN Management Applications	75
SANavigator and EFCM Applications	75
SANvergence Manager Application	81
SANpilot Interface	84
Command Line Interface	86
Planning Considerations for Fibre Channel Topologies	87
Fibre Channel Topologies	87
Characteristics of Arbitrated Loop Operation	88
Shared Mode Versus Switched Mode	89
Public Versus Private Devices	92
Public Versus Private Loops	94
FL_Port Connectivity	96
Planning for Private Arbitrated Loop Connectivity	96
Planning for Fabric-Attached Loop Connectivity	97
Connecting FC-AL Devices to a Switched Fabric	97
Server Consolidation	98
Tape Device Consolidation	99
Fabric Topologies	100
Mesh Fabric	100
Core-to-Edge Fabric	102
SAN Islands	104
Planning for Multiswitch Fabric Support	104
Fabric Topology Limits	105
Factors to Consider When Implementing a Fabric Topology	106
General Fabric Design Considerations	115
Fabric Initialization	116
Fabric Performance	117
Fabric Availability	123
Fabric Scalability	125
Obtaining Professional Services	126
Mixed Fabric Design Considerations	126
FCP and FICON in a Single Fabric	127
Multiple Data Transmission Speeds in a Single Fabric	137
FICON Cascading	138
High-Integrity Fabrics	139
Minimum Requirements	140
FICON Cascading Best Practices	141
Implementing SAN Internetworking Solutions	145
SAN Island Consolidation	146
Flexible Partitioning Technology	148
SAN Routing	152
Implementing BC/DR Solutions	180
Extended-Distance Operational Modes	181
SAN Extension Transport Technologies	183
Distance Extension Through BB_Credit	193
Intelligent Port Speed	195
Distance Extension Best Practices	199
Consolidating and Integrating iSCSI Servers and Storage	202
iSCSI Protocol	203
iSCSI Server Consolidation	204
iSCSI Storage Consolidation	205
Physical Planning Considerations	207
Port Connectivity and Fiber-Optic Cabling	207
Port Requirements	208
SFP Optical Transceivers	209
Extended-Distance Ports	212
High-Availability Considerations	212
Fibre Channel Cables and Connectors	212
Routing Fiber-Optic Cables	214
Management Server, LAN, and Remote Access Support	215
Management Server	215
Remote User Workstations	217
SNMP Management Workstations	219
SANpilot Interface	220
Security Provisions	221
Password Protection	221
SANtegrity Authentication	222
SANtegrity Binding	225
PDCM Arrays	226
Preferred Path	229
Zoning	231
Server and Storage-Level Access Control	235
Security Best Practices	236
Optional Feature Keys	239
Inband Management Access	241
Flexport Technology	242
SANtegrity Authentication	243
SANtegrity Binding	243
OpenTrunking	243
Full Volatility	244
Full Fabric	245
Remote Fabric	245
CNT WAN Support	246
Element Manager Application	246
Configuration Planning Tasks	249
Task 1: Prepare a Site Plan	250
Task 2: Plan Fibre Channel Cable Routing	251
Task 3: Consider Interoperability with Fabric Elements and End Devices	252
Task 4: Plan Console Management Support	253
Task 5: Plan Ethernet Access	254
Task 6: Plan Network Addresses	255
Task 7: Plan SNMP Support (Optional)	258
Task 8: Plan E-Mail Notification (Optional)	259
Task 9: Establish Product and Server Security Measures	259
Task 10: Plan Phone Connections	260
Task 11: Diagram the Planned Configuration	261
Task 12: Assign Port Names and Nicknames	261
Task 13: Complete the Planning Worksheet	262
Task 14: Plan AC Power	276
Task 15: Plan a Multiswitch Fabric (Optional)	277
Task 16: Plan Zone Sets for Multiple Products (Optional)	278
Task 17: Plan SAN Routing (Optional)	279
Task 18: Complete Planning Checklists	282
Product Specifications	287
Director, Fabric Switch, and SAN Router Specifications	287
Dimensions	287
Power Requirements	289
Heat Dissipation	290
Clearances	290
Acoustical Noise and Physical Tolerances	292
Storage and Shipping Environment	292
Operating Environment	293
FC-512 Fabricenter Cabinet Specifications	293
Dimensions	293
Power Requirements	294
Clearances	294
Cabinet Footprint	294
Firmware Summary	297
System-Related Differences	297
Fibre Channel Protocol-Related Differences	299
Management-Related Differences	301

Match case Limit results 1 per page

Implementing SAN Internetworking Solutions

4-27

Implementing SAN Internetworking Solutions

and results in a lower compression bandwidth. The algorithm

has an average compression ratio increase of approximately

30% over LZO. The algorithm is recommended when up to 8

TCP sessions are used and the available bandwidth is between

10 Mbps (thin Ethernet) and 45 Mbps (DS3 transport level).

—

Deflate -

This algorithm incorporates a history cache with

Huffman encoding. In addition, a hash table (saved in the

compressed data) is used to perform string searches. Deflate is

a processor-intensive algorithm with the highest compression

ratio. The algorithm is restricted to use for 10 Mbps (thin

Ethernet) links.

Note that a data compression ratio cannot be definitively stated,

because it changes instantaneously with every data byte

transmitted. A consistent byte pattern can be compressed more

than a random byte pattern. For example, a defined, constant

pattern can often be compressed 15:1. Already-compressed data

(such as many graphic formats and some tape formats) cannot be

compressed further (1:1). Most data streams are compressible

from between 2:1 and 15:1, depending on the density of consistent

patterns. The only way to accurately determine a compression

ratio is to compress the data and measure the result.

•

FastWrite technology -

SCSI is a simplex protocol that sends a

portion of a write command, then waits for a response. Multiple

commands can coexist, resulting in an inefficient process on

high-latency links. FastWrite is an algorithm that reduces the

number of round trips required to complete a SCSI write

command to one round trip. The software improves performance

over WANs by mitigating the effects of latency and using the

entire link bandwidth (because all data is transmitted

simultaneously).

The FastWrite algorithm responds to initiator write commands

with local transfer ready (

XFR_RDY

) commands that cause the

initiator to transmit an entire data set, then buffers the output

data at the SAN router closest to the corresponding target device.

This eliminates multiple

XFR_RDY

command transmissions and

minimizes bursty data transfer over the WAN, thus reducing

round-trip delays that are characteristic of extended-distance

links.