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Charts and Tables

A-6

Workgroup Design Tables

a. This table is subject to change as new BRIM modules and revised firmware are released.

Table A-7. BRIM Reference Table

BRIM

Technology

Connector

Type

BRIM-E6

Ethernet

EPIM

BRIM-E100

Fast Ethernet

EPIM

BRIM-F6

FDDI

FPIM (2)

BRIM-A6

ATM

APIM

BRIM-A6DP

ATM

APIM (2)

BRIM-W6

WAN

WPIM

Table A-8. BRIM Interoperability Table

BRIM

MicroMMAC-

22/24/32/34E

NBR-620

BRIM #1

NBR-620

BRIM #2

ESX-1320/1380

BRIM-E6

YES

BRIM-E100

YES

BRIM-F6

YES

BRIM-A6

YES

BRIM-A6DP

YES

BRIM-W6

YES

Содержание bridges

Страница 1: ...Cabletron Systems Networking Guide Workgroup Solutions...

Страница 2: ......

Страница 3: ...ystems Inc All rights reserved Printed in the United States of America Order Number 9032094 January 1997 Cabletron Systems Inc P O Box 5005 Rochester NH 03866 5005 Cabletron Systems SPECTRUM BRIM FNB...

Страница 4: ...Notice ii...

Страница 5: ...Ethernet 2 3 Token Ring 2 5 Chapter 3 The Workgroup Approach Standalones 3 1 Standalones the Original Networking Devices 3 2 Management of Standalones 3 3 Limitations of Standalones 3 3 Stackables 3...

Страница 6: ...es 5 17 Choosing Backbone Technologies 5 21 Chapter 6 Ethernet Ethernet Workgroup Devices 6 2 Shared Devices 6 2 Switched Devices 6 4 Ethernet Workgroup Design 6 5 The Home Office 6 5 The Small Office...

Страница 7: ...ndix A Charts and Tables Workgroup Design Tables A 1 Ethernet A 1 Fast Ethernet A 3 Token Ring A 4 PIMs and BRIMs A 5 Networking Standards and Limitations A 8 Ethernet A 8 Fast Ethernet A 9 Token Ring...

Страница 8: ...Contents vi...

Страница 9: ...and FDDI If you are unfamiliar with these technologies Cabletron Systems produces instructional and reference materials that may be of assistance in learning these networking technologies The availabl...

Страница 10: ...bletron Systems various speciality interface modules Chapter 5 Network Design covers the information and decisions involved in the identification of networking needs and formation of solutions which m...

Страница 11: ...n of hardware and cabling Cabletron Systems maintains a staff of network design personnel and highly trained cabling and hardware installation technicians The services of the Networking Services group...

Страница 12: ...in greater or lesser detail than they are presented here Cabletron Systems Networking Guide MMAC FNB Solutions Cabletron Systems Cabling Guide Cabletron Systems Ethernet Technology Guide Cabletron Sy...

Страница 13: ...rnet and Token Ring This section is intended to be a review of the most important aspects of these technologies and is not expected to stand alone For more detailed information Cabletron Systems publi...

Страница 14: ...ns listen for network traffic hear none then transmit simultaneously In this case both transmissions are damaged and the stations sensing this collision must retransmit at some later time Backoff algo...

Страница 15: ...t of the popular Ethernet technology described above Fast Ethernet uses the same CSMA CD media access method and basic network operation The main differences between Ethernet and Fast Ethernet are the...

Страница 16: ...and network restrictions in order to adhere to IEEE standards Cabling Quality All 100BASE TX links require UTP cabling meeting or exceeding the Telecommunications Industry Association TIA Category 5 s...

Страница 17: ...dges switches or routers can allow the creation of larger networks Token Ring Token Ring network operation is based on the principle that the operation of the entire network determines when a station...

Страница 18: ...network to suffer errors and poor performance In order to stretch the capabilities of a Token Ring network various technologies are available which extend the distance a signal can travel before suffe...

Страница 19: ...ngs 16 Mbps Token Ring networks also impose limitations on the maximum length of any media connected to an active port as shown in the following list IBM Types 1 2 STP 150 m IBM Types 6 9 STP 100 m Ca...

Страница 20: ...o 16 Mbps networks In one case the number of stations supported by these faster Token Ring networks is significantly lower than the number supported by the 4 Mbps rings IBM Types 1 2 STP 250 stations...

Страница 21: ...mitations involved in the IEEE 802 5 standard and the various cable specifications that are more detailed and complex These limitations are covered in detail in the Cabletron Systems Cabling Guide and...

Страница 22: ...Review of Networking 2 10 Token Ring...

Страница 23: ...of these products can greatly aid a Network Designer in determining where and to what extent to implement standalone and stackable devices in a new or existing network Standalones A standalone device...

Страница 24: ...rks grew in size the standalone devices began to offer greater control and expandability The design of multiport repeaters allowed one signal to be sent out several interfaces simultaneously and the s...

Страница 25: ...lexity The modular chassis allowed facility networks to support far greater numbers of users from a single location than was possible with standalone devices Limitations of Standalones In time the net...

Страница 26: ...number of standalone devices In effect the stack fools the network into thinking that the users connected to the stack are in a single repeater or concentrator By placing stackables together in a coll...

Страница 27: ...nnect Cables The HubSTACK cables handle the communications between stackable devices including network traffic and management communications The use of these custom short cables allows the stack to ac...

Страница 28: ...rvices for the rest of the devices in its stack over the same connection that is used for stackable to stackable communications The management traffic moves across the artificial backplane that is set...

Страница 29: ...rt a wide variety of networking technologies The available BRIMs and their configuration options are detailed in Chapter 4 PIMs and BRIMs By incorporating the BRIM technology into a number of standalo...

Страница 30: ...transceivers at each location While not extremely expensive these external transceivers can become maintenance and design hurdles when troubleshooting or expanding the network Modules for modular cha...

Страница 31: ...tch platform such as the Cabletron Systems MMAC Plus It is important that workgroup devices be able to support complexity so Cabletron Systems has designed support for different media segmentation and...

Страница 32: ...link Types of PIMs To provide connectivity options for the widest variety of networking needs and to increase the flexibility of Cabletron Systems networking devices there are several types of PIMs av...

Страница 33: ...equipment The EPIMs that are available from Cabletron Systems and the types of cabling and connectors supported by each are listed below EPIM A AUI DB15 Female Connector EPIM C Coaxial Cable RG 58 Co...

Страница 34: ...lded Twisted Pair DB9 Connector TPIM T2 Unshielded Twisted Pair RJ45 Connector TPIM T4 Shielded Twisted Pair RJ45 Connector FPIMs FPIM stands for FDDI Port Interface Module The FPIM is a single link f...

Страница 35: ...ported by the available APIMs are listed below APIM 11 Multimode Fiber Optic TAXI connection APIM 21 Multimode Fiber Optic OC3c connection APIM 22 Single Mode Fiber Optic OC3c connection APIM 29 Unshi...

Страница 36: ...T EPIM F3 Ethernet Single Mode Fiber Optics ST EPIM T Ethernet UTP RJ45 EPIM X Ethernet AUI DB15 Female Fast Ethernet Interface Module 100TX Fast Ethernet UTP RJ45 Fast Ethernet Interface Module 100FX...

Страница 37: ...ber Optics SC APIM 11 ATM TAXI Multimode Fiber Optics SC APIM 21 ATM OC3c Multimode Fiber Optics SC APIM 22 ATM OC3c Single Mode Fiber Optics SC APIM 29 ATM STS3c UTP RJ45 APIM 67 ATM DS3 Thin Coaxial...

Страница 38: ...lities are needed a BRIM can be added to any BRIM capable device This gradual upgrade path allows Network Designers to plan ahead for the incorporation of new technologies without having to pay for th...

Страница 39: ...single BRIM F6 match for the sake of consistency and ease of cable and connector management BRIM A6 The BRIM A6 provides a single ATM uplink for the LAN device it is placed in The BRIM A6 supports a v...

Страница 40: ...can be useful for the selection of a BRIM when designing a workgroup requiring a connection to a particular networking technology Table 4 2 BRIM Reference Table BRIM Technology Connector Type BRIM E6...

Страница 41: ...figuration is the process of putting hardware together to create a functioning network NOTES When designing a network installation or configuration draw the network At the very least make a rough sket...

Страница 42: ...y of enterprise networks are collections of workgroups that are connected to one another The various workgroups all have different needs and implementations and are tied together to form a cohesive an...

Страница 43: ...n does not take function into account As the deciding criteria for this type of workgroup organization is location only geographical proximity is often the least efficient workgroup creation method in...

Страница 44: ...ions Since most of the time business departments are involved with sharing information among other members of their department or a group of related departments Accounting Personnel and Payroll for ex...

Страница 45: ...ization troubleshooting and fault recovery can be difficult in a network of this kind As the end users are not necessarily located in the same area faults which affect the workgroup must be looked for...

Страница 46: ...ving etc and one workgroup which encompassed only the Documentation personnel of each department who although working in different departments all require access to the same functions through the netw...

Страница 47: ...cs Unfortunately it combines some of the worst features of the other methods of arranging workgroups as the cost of this level of control An example of priority organization is the common practice of...

Страница 48: ...network based on their relative importance the priority organization method makes little or no accommodation for the localization of network traffic which is the purpose of segmentation If a file ser...

Страница 49: ...is the job of the Network Manager or persons designing the network to determine which factors of the network design are the foremost requirements The most common determining factors in selecting a net...

Страница 50: ...and the network will be much easier to see as a whole The network plan in the design stages of networking can point out areas that need additional work help you locate possible trouble spots and allo...

Страница 51: ...to remember when planning cabling installations is that attention to detail will pay off You may save a few hours at installation by not labeling your cables but those saved hours will be more than sp...

Страница 52: ...ered by contingencies or their effects are minimized This aspect of network design is called fault aversion A fault averse network uses the capabilities of available hardware and the fault tolerance o...

Страница 53: ...e point of failure but only from the point of view of the connection between segments as the segments themselves will continue to operate without the repeater The location and elimination of single po...

Страница 54: ...fail often or be shut down on the dual ring where they will benefit from the automated recovery feature Network Maps and Record Keeping A large portion of the process of expanding an existing network...

Страница 55: ...ron Systems Ethernet bridge NBR 220 If in the future this device is upgraded the map can remain the same but the device code table or chart can be changed If for example the NBR 220 was upgraded to an...

Страница 56: ...makes up the workgroup in order to add special functions What actions will be taken if the facility expands or constructs another separate office All of these questions should be examined before selec...

Страница 57: ...or hub to a small backbone network than to continue expanding workgroups that may be already quite congested In addition the backbone can provide a point from which a higher speed technology can be pa...

Страница 58: ...ttached to a shared bus such as a thick coaxial cable Limited Expandability While it is possible to simply add stations to a thick Ethernet backbone the ring dependent technologies Token Ring and FDDI...

Страница 59: ...ions provided by the collapsed backbone often outweighs the associated costs Connectivity Requirements The collapsed backbone implementation brings all cables of the backbone to a central point and th...

Страница 60: ...e the connections between workgroups greatly increases the control that Network Managers have over the network and may improve performance by streamlining the communications between networks Figure 5...

Страница 61: ...operation of each type of technology the strengths and shortcomings of those technologies and the special design considerations that each technology imposes on the network You may again wish to refer...

Страница 62: ...Network Design 5 22 The Workgroup in the Larger Network...

Страница 63: ...ducts Once the proposed network has been broken into a number of workgroups it is necessary to begin designing the actual solutions for those workgroups and selecting hardware for use in them The info...

Страница 64: ...twork segment The available devices are listed in Table 6 1 below The columns in Table 6 1 indicate some of the most important data to be considered when selecting networking devices for a particular...

Страница 65: ...ent support Cabletron Systems SNMP implementation which includes the functions of SNMP Management Information Base II MIB II and the Cabletron Proprietary MIB RMON capable devices include all SNMP fun...

Страница 66: ...ort Count Port Count indicates the number of fixed media ports there are on the device In a case where a device has zero ports it means that the device has no dedicated media ports and all connections...

Страница 67: ...a small number of stations low data transfer needs and limited expected expansion requirements While most networks of this sort are located in homes or small family businesses the home office descrip...

Страница 68: ...rimary selection criteria and one that quickly divides Ethernet networking devices into compliant and non compliant categories Manageable or intelligent devices while more costly than non intelligent...

Страница 69: ...later in this chapter Expandability The importance of a smooth and simple path for adding users to the home office network is something that while usually not a driving factor in the decision making p...

Страница 70: ...These specialized considerations are beyond the scope of this document but a large amount of information can be found in the Cabletron Systems Networking Solutions Product Guide Design Example The exa...

Страница 71: ...vices the Network Designer removes those intelligent devices from the selection field The products removed from the field are not fully discarded from consideration however If the remaining non intell...

Страница 72: ...criteria prove that the remaining devices in the selection field do not measure up to the network s needs these can be reintroduced to the selection field The easiest decision in the process of home...

Страница 73: ...etworks within a larger facility or to departmental workgroups that are connected through their native networking technology to other portions of the corporate or facility network The small office unl...

Страница 74: ...devices The benefits of management come at a cost of higher final product prices and may not be fully recognized by extremely small or simplistic networks The small office level is truly the middle gr...

Страница 75: ...ficient port availability to cover the vast majority of small offices without requiring links to other stacks or devices Price As always the price factor must be considered in the network design proce...

Страница 76: ...Figure 6 3 with most of the stations 21 located in the Business Office The Business Office also contains three server stations two for file storage and retrieval and one for printing The Loading Dock...

Страница 77: ...highest port count to the total station count of the proposed network the Network Designer notices that the SEHI 24 alone does not meet the total required number of stations 27 While it would be possi...

Страница 78: ...res a connection to a different networking technology in order to make a connection to a larger or physically separate network In the classical sense this refers to a branch office location that has a...

Страница 79: ...on process can begin BRIM Selection As most remote office environments will deal with BRIM capable standalone or stackable devices the selection of the correct BRIM is an essential portion of the netw...

Страница 80: ...e certain that the network that is being considered will work the Network Designer consults the table of BRIM interoperability and determines that the BRIM W6 will in fact work properly in the MicroMM...

Страница 81: ...ing high throughput Since each Ethernet link is dedicated and will receive traffic from no other sources than the station and the switch if the network is within the allotted limitations the Ethernet...

Страница 82: ...even bridges in the longest signal path Since this bridge rule can severely limit the magnitude of networks incorporating per port switching on a large scale the expansion of high end workgroups is of...

Страница 83: ...ffective way to provide more bandwidth to each end station is through per port switched Ethernet connections The CAD department consists of 16 CAD designers 2 CAD image file servers and 3 plotters all...

Страница 84: ...ificant benefit over those solutions the NBR 620 is removed from consideration This leaves the selection field with the ESX 1320 and ESX 1380 two Ethernet switches that support RMON management one BRI...

Страница 85: ...rt the Network Designer finds that the BRIM F6 is the BRIM that is needed This FDDI BRIM requires two FDDI Port Interface Modules or FPIMs Matching the media type of the corporate backbone to the medi...

Страница 86: ...There are four classrooms and two labs to be connected to the backbone and there is expected to be growth in the number of Ethernet workgroups at the college in the future The connections from the cl...

Страница 87: ...s a series of examples for different Fast Ethernet network approaches Fast Ethernet Workgroup Devices The following sections present and describe the various Cabletron Systems workgroup networking dev...

Страница 88: ...that is supplied by Table 6 2 for Ethernet switching devices a These products can be managed through the addition of an intelligent stackable device to their stack Table 7 1 Shared Fast Ethernet Work...

Страница 89: ...proposed workgroup as a template for design Small Offices The term small office as it applies to Fast Ethernet installations using Cabletron Systems workgroup devices can be misleading This workgroup...

Страница 90: ...o be used If the EPIM slots are all used the Fast Ethernet stack will reach its limitation of 119 users Any Fast Ethernet workgroup containing more than 119 stations will require the creation of anoth...

Страница 91: ...he network Examining the selection filed the Network Designer selects the SEHI100TX 22 which provides SNMP management functions As the SEHI100TX 22 is a stack base any non intelligent SEH100TX 22 hubs...

Страница 92: ...ations of Fast Ethernet the design approach and decisions required of high end departments using the Fast Ethernet technology do not differ much from those used for normal Ethernet designs In the same...

Страница 93: ...t switches are not as easily expanded to accommodate new connections as stackable hubs are it may be wise when designing a Fast Ethernet workgroup to provide extra connections This kind of forethought...

Страница 94: ...e a compliant device for this network implementation the Network Designer examines the Cabletron Systems Networking Solutions Product Guide to determine the fitness of the FN100 16TX for this particul...

Страница 95: ...st Ethernet switch but the connections in the backbone solution are made to workgroups rather than individual stations Design Example As an example of the methods used to design a switched Fast Ethern...

Страница 96: ...ures or performance losses are exceedingly difficult to troubleshoot Access to the three shared file servers Archive1 Archive2 and StockPhoto is required by all departments and users have been complai...

Страница 97: ...Server Optimizations These switched station connections will provide full Fast Ethernet speed connections to each of the fileservers While this will introduce a switch into the path from any station...

Страница 98: ...BRIM The Network Designer examines the available BRIMs that can be placed in the MicroMMAC 24Es The BRIM E100 when configured with the proper Fast Ethernet Interface Modules will provide a Fast Ethern...

Страница 99: ...ner than the other technologies treated in this document Token Ring Workgroup Devices The following sections present and describe the various Cabletron Systems workgroup networking devices that may be...

Страница 100: ...s field a These products can be managed through the addition of an intelligent stackable device to their stack Table 8 1 Token Ring Workgroup Devices Product Type Max Management Media Port Count PIMs...

Страница 101: ...ign Process The procedures and decisions involved in designing a Token Ring network are quite straightforward and simple Once it has been established that all the station cabling is within the allotte...

Страница 102: ...ps the easiest and most straightforward portion of the Token Ring network design process As all of the Cabletron Systems standalone Token Ring networking products are also stackable devices any time a...

Страница 103: ...and has decided that a single 16Mbps Token Ring network will offer the necessary performance and reliability to this network The cabling to be used will be Category 5 UTP cable and all the cable runs...

Страница 104: ...I 24 and four TPIMs of a matching media type and connect the two devices through the RI RO ports This solution while ideal in situations where users are widely dispersed or located in separate facilit...

Страница 105: ...or 24 ports of station connectivity The addition of an STH 24 to the STHI 24 already in the design would supply 48 ports of Token Ring station connectivity and four RI RO ports for future links if re...

Страница 106: ...Token Ring 8 8 Token Ring Workgroup Design...

Страница 107: ...rnet Workgroup Devices Product Type Max Management Media Port Count PIMs BRIMs MR9T E repeater NONE UTP 8 1 EPIM SEH 22 32 stackable NONEa UTP 12 1 EPIM SEH 24 34 stackable NONEa UTP 24 2 EPIMs SEH 22...

Страница 108: ...a Port Count Switch Interfaces PIMs BRIMs NBR 220 SNMP 0 2 2 EPIMs NBR 420 SNMP 0 4 4 EPIMs NBR 620 SNMP 0 6 4 EPIMs 2 BRIMs FN10 SNMP UTP 12 24 12 24 0 ESX 1320 RMON UTP 12 13 1 BRIM ESX 1380 RMON Mu...

Страница 109: ...0 FN100 16TX SNMP UTP 16 16 0 FN100 8FX SNMP Multimode Fiber Optics 8 8 0 FN100 16FX SNMP Multimode Fiber Optics 16 16 0 Table A 5 Token Ring Workgroup Devices Product Type Max Management Media Port C...

Страница 110: ...T Ethernet UTP RJ45 EPIM X Ethernet AUI DB15 Female Fast Ethernet Interface Module 100TX Fast Ethernet UTP RJ45 Fast Ethernet Interface Module 100FX Fast Ethernet Multimode Fiber Optics SC Fast Ether...

Страница 111: ...Fiber Optics SC APIM 11 ATM TAXI Multimode Fiber Optics SC APIM 21 ATM OC3c Multimode Fiber Optics SC APIM 22 ATM OC3c Single Mode Fiber Optics SC APIM 29 ATM STS3c UTP RJ45 APIM 67 ATM DS3 Thin Coaxi...

Страница 112: ...nnector Type BRIM E6 Ethernet EPIM BRIM E100 Fast Ethernet EPIM BRIM F6 FDDI FPIM 2 BRIM A6 ATM APIM BRIM A6DP ATM APIM 2 BRIM W6 WAN WPIM Table A 8 BRIM Interoperability Table BRIMa MicroMMAC 22 24 3...

Страница 113: ...Table A 9 Ethernet Standard Distance Limitations Media Max Distance Thick Coax 500 m Thin Coax 185 m Standard AUI 50 m Office AUI 16 5 m UTP 100 m Fiber Optics Multimode 1000 m Fiber Optics Single Mo...

Страница 114: ...t Ethernet 100BASE TX FX Distance Limitations Media Max Distance UTP 100 m Fiber Optics Multimode 412 m Table A 12 Fast Ethernet Maximum Network Radii Repeater Class UTP UTP Fiber Optics Fiber Optics...

Страница 115: ...Cable Type Max of Stations Max Lobe Length 4 Mbps 16 Mbps 4 Mbps 16 Mbps STP active IBM Types 1 2 250 250 300 m 150 m IBM Types 6 9a 250 136 200 m 100 m passive IBM Types 1 2 250 250 200 m 100 m IBM...

Страница 116: ...Media Max Distance 4 Mbps Max Distance 16 Mbps Shielded Twisted Pair 770 m 346 m Unshielded Twisted Pair Category 3 4 200 m 100 m Category 5 250 m 120 m Fiber Optics Multimode 2000 m 2000 m Fiber Opt...

Страница 117: ...1 STP cabling only Table A 16 FDDI Distance Limitations Media PMD Standard Max Link Distance Fiber Optics Multimode MMF PMD 2 km Fiber Optics Single Mode SMF PMD 60 km Unshielded Twisted Paira TP PMD...

Страница 118: ...Charts and Tables A 12 Networking Standards and Limitations...

Страница 119: ...rns the operation of devices connecting to Ethernet thin coaxial cable 10BASE5 IEEE standard which governs the operation of devices connecting to Ethernet thick coaxial cable 10BASE FL IEEE standard w...

Страница 120: ...raffic to be passed between the separate networks when necessary Bridges read in packets and decide to either retransmit them or block them based on the destination to which the packets are addressed...

Страница 121: ...cting signals on another strand or set of strands CSMA CD Carrier Sense Multiple Access with Collision Detection CSMA CD is the basis for the operation of Ethernet networks CSMA CD is the method by wh...

Страница 122: ...M ports of two separate dual attached concentrator devices providing fault tolerance EEPROM Electronic Erasable Programmable Read Only Memory Encryption A security process which encodes raw data into...

Страница 123: ...an FNB configured chassis to support multiple network technologies simultaneously Frame A group of bits that form a discrete block of information Frames contain network control information or data The...

Страница 124: ...s is controlled by the IANA ISO International Organization for Standardization The ISO has developed a standard model on which network operation is based called the OSI Model Jitter Degradation of net...

Страница 125: ...he purposes of creating a network or networks Module A discrete device which is placed in a modular chassis to provide functionality which may include but is not limited to bridging routing connectivi...

Страница 126: ...del and are encapsulated in frames before being transmitted onto a network media Passive Not utilizing per port reclocking and regeneration of the signal which is propagated throughout the device Comm...

Страница 127: ...dia Interface Module A term used to indicate a family of Cabletron Systems Ethernet Media Interface Modules See MIM which are capable of performing their own repeater functions Router A router is a de...

Страница 128: ...dges to selectively activate some ports while others remain in a standby condition avoiding the data loops and providing redundant paths in the event of bridge failures SQE Signal Quality Error A self...

Страница 129: ...nd pass the token along to the next station in the network Token Ring A network technology which requires that stations only transmit data when they have been given permission by the reception of a To...

Страница 130: ...UTP to UTP Glossary 12...

Страница 131: ...5 18 Document conventions 1 3 Document organization 1 2 E EPIM 4 3 Ethernet 2 2 6 1 cable lengths 2 2 high end department 6 19 home office 6 5 remote office 6 16 shared devices 6 2 signal path 2 3 sma...

Страница 132: ...e office 6 16 Repeater 3 2 Ring In Ring Out 2 6 S Segmentation 5 2 Small office 6 11 7 3 8 3 Stackable 3 4 interconnect cable 3 5 internetworking 3 7 management 3 6 Standalone 3 1 management 3 3 T Tec...

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