Cabletron Systems TRFOT-3 Spezifikationen

Cabletron SystemsTOKEN RINGTECHNOLOGY OVERVIEW

TOKEN RING OVERVIEW2-2 TOKEN RING TOPOLOGY The Token Ring topology, or logical shape, is a ring. A ring topology is a point-to-point network in which

2-3TOKEN RING OVERVIEW LOCAL AREA NETWORK STANDARDS Networking standardization has one goal: to allow systems to communicate with each other. This is

TOKEN RING OVERVIEW2-4 Physical (Layer One) This layer interfaces directly to the physical medium and is responsible for sending and receiving a stre

2-5TOKEN RING OVERVIEW Application (Layer Seven) This layer provides access to the OSI environment and provides communication based services to the e

TOKEN RING OVERVIEW2-6 Access Method Communication between devices on a network requires that there be a common method for transmitting and receiving

2-7TOKEN RING OVERVIEW 8. Through the use of simple time-out circuits, the ring has a means of protection against a station that fails to pass the to

TOKEN RING OVERVIEW2-8 PHYSICAL LAYER The Token Ring topology is characterized as a logically circular, unidirectional transmission path without defin

2-9TOKEN RING OVERVIEW Lobe Cable The lobe cable is used to attach a station the TCU on an MSAU. In practice lobe cabling can consist of various cabl

TOKEN RING OVERVIEW2-10 Ring De-Insertion If the station’s hardware adapter experiences a non-recoverable error, the phantom current will drop causin

2-11TOKEN RING OVERVIEW With Differential Manchester Encoding the sequence of signal polarities is completely dependent on the polarity of the second

TOKEN RING OVERVIEW2-12 when the AM loses power. The process to select a new AM is known as Monitor Contention. The process to select the new AM begi

2-13TOKEN RING OVERVIEW its transmit clock. This problem is known as Accumulated Jitter and is one of the main reasons for the limitations on the num

TOKEN RING OVERVIEW2-14Station InsertionThe act of powering up a station does not immediately enable it to become part of the ring. Certain tests are

2-15TOKEN RING OVERVIEWRing Poll Process If there is no duplicate address on the ring, the station participates in neighbor notification by learning it

TOKEN RING OVERVIEW2-16The Standby MonitorAll other stations are Standby Monitors (SMs). The SMs verify that the AM is on the ring and performing its

2-17TOKEN RING OVERVIEWTherefore, the station with the highest address eventually receives its own Claim Token MAC frame back, allowing it to reissue

TOKEN RING OVERVIEW2-18• Station B still has a frame to transmit but it cannot capture the present token, which is set to priority 3; it only has a pr

2-19TOKEN RING OVERVIEWEach station on the ring, as it receives the PRG frame, cancels all timers and resets to normal repeat mode, if the frame canno

TOKEN RING OVERVIEW2-20SOURCE-ROUTE BRIDGING METHODSource-route bridging is the predominant method used for linking Token Ring LANs. Source-route brid

2-21TOKEN RING OVERVIEWSource RoutingUpon receiving an SRF, a bridge looks for the following information in the RIF:• The ring number of the receiving

i NOTICE Cabletron Systems reserves the right to make changes in specifications and other information contained in this document without prior notice.

TOKEN RING OVERVIEW2-22TOKEN RING MANAGEMENTAccording to the IEEE 802.5 standards, each ring station or Network Interface Card (NIC) has the ability t

2-23TOKEN RING OVERVIEWClaim Token Process (CL_TK)All stations are capable of being the AM, while others remain as SMs. The establishment of an AM is

TOKEN RING OVERVIEW2-24Remove Ring Station (REMOVE)The CRS transmits this frame to a certain station when unconditional removal of that station is req

2-25TOKEN RING OVERVIEWRequest Ring Station State (RQ_STATE)This frame is transmitted by any of the management servers to a station. It is a request f

TOKEN RING OVERVIEW2-26Abort FormatThis frame sequence shown in Figure 2-4 is used by a station to terminate its transmission prematurely. The Startin

2-27TOKEN RING OVERVIEWStarting Delimiter (SD)The SD is always the same pattern of 8 bits - J K 0 J K 0 0 0.Both J and K violate the Differential Manc

TOKEN RING OVERVIEW2-28Ending Delimiter (ED)The ED has the following format:J K 1 J K 1 | I | EThe first 6 bits, J K 1 J K 1, are always the same. Note

2-29TOKEN RING OVERVIEWFigure 2-6. Data Frame StructureStart of Frame and End of Frame SequencesThe SD and AC fields are referred to as Start of Frame

TOKEN RING OVERVIEW2-30Figure 2-7. Frame Control Field FormatDestination Address (DA)The DA field shown in Figure 2-8 contains the address of the stati

2-31TOKEN RING OVERVIEWFigure 2-8. Destination Address FieldMAC Frame FormatMAC frames are originated, received, and acted upon by stations. These fra

NOTICEii

TOKEN RING OVERVIEW2-32Figure 2-9. MAC LLID Field FormatThe Major Vector consists of a MAC length and ID (LLID) and 0, 1, or more MAC sub-vectors.The

2-33TOKEN RING OVERVIEWIf the frame type is a MAC frame, all stations on the ring act on the state of ZZZ control bits of the Frame Control field.There

TOKEN RING OVERVIEW2-340C Change Parameters00 Station Config. Report Server03, 04, 05,06, 07, 090D Initialize Ring 00 Station Ring Parameter Server 03,

2-35TOKEN RING OVERVIEWConfiguration Report ServerThe Configuration Report Server is a network management function that resides on every ring in a multi

TOKEN RING OVERVIEW2-36Ring Parameter ServerThe ring Parameter Server is a network management function that resides on every ring in which the operati

3-1Chapter 3TOKEN RING DEVICES AND APPLICATIONSThis chapter lists severalToken Ring products available from Cabletron Systems and presents examples of

TOKEN RING DEVICES AND APPLICATIONS3-2Figure 3-1. MMACsConcentratorsModular concentrators install in the MMAC and provide multi-station access to the

3-3TOKEN RING DEVICES AND APPLICATIONSMedia Flexibility and ConversionToken Ring networks can be wired with different types of media. Cabletron System

TOKEN RING DEVICES AND APPLICATIONS3-4Token Ring Management ModulesCabletron provides network management modules that allow a network manager to monit

3-5TOKEN RING DEVICES AND APPLICATIONSFigure 3-3. Expanded Token Ring NetworkMULTIPLE TOKEN RINGS IN ONE MMACMore than one Token Ring can be configured

iii CONTENTS CHAPTER 1 INTRODUCTION USING THIS MANUAL...

TOKEN RING DEVICES AND APPLICATIONS3-6Figure 3-4. Multiple Token Ring Configurations in an MMACBRIDGED TOKEN RING NETWORKS Figure 3-5 illustrates the b

3-7TOKEN RING DEVICES AND APPLICATIONSFigure 3-5. Using a Bridge to Connect Ring NetworksTRBMIM-TPhysical Bridge LinkMedia interface Module16 Mbps Rin

TOKEN RING DEVICES AND APPLICATIONS3-8

4-1Chapter 4TOKEN RING NETWORK CABLINGThis chapter provides an overview of the different cable types used for Token Ring networks. It covers basic cab

TOKEN RING NETWORK CABLING4-2TERMINOLOGYThis section covers some of the basic terminology used in reference to Token Ring cabling concepts.Attentuatio

4-3TOKEN RING NETWORK CABLINGPatch PanelA patch panel is a device that serves as a junction for interconnecting lobe- and trunk-cable segments. RJ Con

TOKEN RING NETWORK CABLING4-4STP CABLE SPECIFICATIONSThe following is a summary of cable specifications that apply to STP cabling used with Cabletron S

4-5TOKEN RING NETWORK CABLINGAttenuationMaximum attenuation for specific cable types at 4 and 16 megahertz is shown by Table 4-2. The attenuation value

TOKEN RING NETWORK CABLING4-6Cable ConnectorsMedium Interface Connector (MIC)The MIC, shown in Figure 4-3, is typically found on IBM Type 6 and 9 patc

4-7TOKEN RING NETWORK CABLINGRJ45 ConnectorThe 8-pin telephone type RJ45 connector shown in Figure 4-5 is found on STP cable used for lobe and trunk c

CONTENTSiv TOKEN RING MANAGEMENT...2-22FRAME TYPES ...

TOKEN RING NETWORK CABLING4-8Recommended Maximum Cable Lengths and StationsTable 4-3 lists recommended trunk (RI/RO) and lobe lengths for UTP cable ty

4-9TOKEN RING NETWORK CABLINGFiber Optic ConstructionA fiber optic cable is composed of a pair of strands, one used for transmit and the other for rece

TOKEN RING NETWORK CABLING4-10MultimodeThere are two types of multimode fiber optic cable: step index and graded index. Both types are typically used f

1-1 Chapter 1 INTRODUCTION Welcome to the Token Ring Network Technology Overview. It provides an introduction to Token Ring network concepts and phy

INTRODUCTION1-2

2-1 Chapter 2 TOKEN RING OVERVIEW This chapter introduces Token Ring features and describes characteristics that distinguish Token Ring from other L